AmericanLongRifles Forums
General discussion => Gun Building => Topic started by: Smokey Plainsman on October 05, 2018, 07:10:22 AM
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Hello all! Another question, here. :)
What do you folks think about round (or radiused) bottom rifling for gun barrels?
I’m hearing some say they’re easier to clean at the end of the day, and that they can allow more shots before needing to swab the bore, and things of that nature. As far as accuracy goes some of the top barrel makers claim between it and square bottom rifling any difference is so small as to be meaningless unless competing at the national target shooting level.
Any truth to any of this? That sure sounds good to me as far as the benefits go. I’m mostly interested in an offhand shooting and small game hunting gun for my .40 caliber. I have picked a swamped 42” round bottom rifling barrel by Rice for the TVM order I recently submitted. Hoping it was a decent choice and just gathering more information on the subject.
Thoughts?
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I don't think I have anything but round -bottomed rifling Smokey, and I like what I have.
My own rifling is round -bottomed.
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I have used both types from Rice and they shot well. You will not be disappointed. I think that the ball size, patch thickness, and lube is easier to work out with the round bottom rifling. I don't have any real technical basis to feel this way other than personal feelings. I was using the square cut all the time unless a customer requested the round bottom rifling because I feel it is more correct for the type of rifles I like to build. However, I have changed over to using the round bottom on everything now. Both types shot great. Good luck with your build.
Roger Sells
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I have a couple of barrels with round bottom rifling. I can't say they are more accurate than squared rifling but they seem to foul less in my .40 (might be my imagination) and cleaning is a breeze. I like them so much that my Kibler Colonial wears a .58 barrel with round bottom rifling. This was not determined by empirical scientific evidence but, just a gut hunch from over 40 years of making smokepoles and shooting them.
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This last Sunday I shot a match with a .54 GRRW. barrel. 27 shots in all. Square bottom rifling. .018 pocket drill, bear lube 60 grains and 95 grains of Goex 2f. a.535 ball on top. Only cleaned once after one relay because we took a lot longer than normal to resume shooting. Clean up , which I did at the range was no harder than cleaning the round bottom rifling on the .54 Rayl barrel that I shot fifteen shots out of yesterday. Same patching .530 ball 60 grains 2f Goex. Personally I wouldn't pay the extra $40.00 for round bottom rifling. You will not get a significant cleaning advantage. I've had other round bottom Rice barrels and saw no advantage or disadvantage over square rifling.
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from my experience round bottom rifling defiantly cleans easier, but you need a thicker patch to fill the deeper grove's and a tighter load. I use square bottom now, but miss round bottom at cleaning time.
turtle
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Friend,
I have radius groove rifling most of my rifles. I think they clean-up easier. I fired 51 rounds in a match one day with my 54 caliber hunting rifle, by friend was using my rifle to continue competing when the mainspring on his gun broke on the first shot, and didn't wipe the bore once. I don't know that the radius groove rifling contributed to that - I think having the right load gets most of the credit. After all that shooting the rifle cleaned-up just as easy as after a 12 round woods-walk.
I have heard that square groove rifling is more accurate but I am not a good enough shot to be able to notice.
My future rifles that I build for me will all have radius groove rifling.
Best Regards,
JMC
John Cholin
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you need a thicker patch to fill the deeper grove's and a tighter load.
With round bottom rifling, I have found that I need more patch thickness to make sure the grooves get filled completely with patch upon loading. With a thinner patch, the grooves don't get filled, and the gasses blow by, burning the patch at the grooves.
A muzzle contour like Darryl uses, helps immensely when trying to load a thick patch.
For smaller bores, I would tend to use square rifling, as I don't need so much patch. Calibers .60 and above, I like the round bottom rifling.
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Interesting about caliber. I tried one round bottom Colerain in 45 cal. I don't like it at all. I can not get really fine accuracy out of it. I prefer regular square bottom and conventional to shallow dept. Sounds like RB works better in larger bore rifles.
I would really like to try Pope style rifling. Because it has the shallowest possible grooves yet is a polygonal-conventional hybrid, it gets maximum purchase on the bullet. The thin patches should work. Unfortunately, I can not find anyone to make such a barrel for me.
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I just ordered two barrels from Rice and decided to stick with flat bottom rifling in each of then. One is a .32 and the other will be a .54.
The only experience I have had with round bottom occurred many years ago when Hoppy Hopkins started making round bottom. I built a gun with said barrel and can not say it shot or performed any better or worse then my flat bottom stuff. Frankly, I don't remember it cleaning any better but it was a long time ago.
The one thing I do remember is during load work up I really had to fool with patch thickness and powder load, as has been mentioned above, in order to squeeze out its capabilities........
I am going to stick with flat bottom and tight patches.....
Just my thoughts.
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I just ordered two barrels from Rice and decided to stick with flat bottom rifling in each of then.
I am glad that Rice is offering the 32 in flat bottom rifling. The last two 32's I got were radius rifled and at the time the 32 was only offered in radius rifling. I prefer flat bottom rifling.
Dennis
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As Acer Sac. noted, muzzle 'shape/condition' can help in loading a tight combination, usually needed for accurate and clean shooting in a rounded bottomed rifling.
Since most rounded rifling is usually .016" to .025" deep (some MUCH deeper than that) the patch thickness and ball size can be much more critical, especially is using heavier hunting-type loads.
The reason for that is increased pressure generated by heavier loads stress the ball/patch fit much more than lighter, plinking-type loads.
I have and have used a number of different barrels using both types of rifling. After 46 years in this hobby, I find picking a ball and patch that will fit and shoot well, to be quite easily accomplished.
I prefer square rifling myself, from about .008" in small .30's bore sizes, to.010" to .012" deep in larger .040 to my .69. I find this rifling cleans virtually the same as rounded rifling. I have no
preference for cleaning. Both need 1 patch for pumping the water into and out of the bore, along with 4 or 5 drying patches afterwards. I always remove the barrel for cleaning and clean in a
container of water.
Here are a few groups fired with VERY deep rifling, some .028" deep. Note with the light 85gr. load, the accuracy was quite good with a .022" canvas patch.
When we went to a heavier load, we used a heavier .034" patching and achieved similar accuracy.
The switch to thicker patching was an automatic change after just firing a couple shots with the lighter .022" canvas patch and checking them. We found shredded burnt patches resulted as the
thin patch did not fill the rifling even though we were using a ball only .005" smaller than the bore. BTW- the .034" patches we used were marked "reclaimed" as they had originally been
fired from my .69calibre rifle, picked up and kept for future use. I maintain that if once fired patches are not reusable, they were not thick enough or of the proper material. 100% cotton or linen
works well, but must be of the correct thickness.
Note that in a .60 cal. rifle, 110gr. 2F is not a high pressure load, but enough over 85gr. to demand thicker patching.
(https://image.ibb.co/nkScZK/60_Hawken_Groups_1.jpg) (https://ibb.co/hFOvMz)
(https://image.ibb.co/hcxN1z/60_Hawken_Groups_2.jpg) (https://ibb.co/mjsBuK)
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I have barrels with rifling from about .006" to .016". Two of the barrels are Rice radius groove barrels, a .32 and a .50. I like the round groove barrels especially for hunting and general "all around" rifles. They do seem to clean a bit faster but I'd call it "inconclusive". I also have 5 square cut barrels and like them as well. About the only thing I'm sure of is that for a target barrel I'd pick a straight, square groove barrel. But I can no longer see to shoot as well as I once did; so for me it doesn't really matter which one.
I like thicker patch material and it does indeed work very well in the rb barrels. With the smooth muzzle crowns both types load easily for me and need no wiping until I leave the range.
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There are modified rifling styles, some with basically flat grooves, but with a small radius between the land and the groove, leaving most of the groove flat.
Does the top driving corner lose some of its ability to drive the ball accurately? And this would be a custom barrel maker most likely.
Is the juice worth the squeeze?
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Dennis:
Those two barrels were ordered earlier this week and when I told Jason I wanted flat bottom in both barrels he never said anything about the .32.
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Seems as if most prefer square bottom rifling...
I fear I’ve made a mistake ordering round bottom! I didn’t know round bottom rifling causes blown patches and so on. :'(
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You will be fine with the round bottom rifling. You will be able to work out patching issues during load development.
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Dennis:
Those two barrels were ordered earlier this week and when I told Jason I wanted flat bottom in both barrels he never said anything about the .32.
I am going to check the Rice 32 that is on my Kibler kit 32. I hope its flat bottom rifling.
I am sure Jason would have mentioned it if they didn't offer flat bottom in a 32.
Back when I got my first Rice 32 I paid extra for it being a 32 (extra work to make) and only offered with radius rifling. That was probably over 5 years ago.
Dennis
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You might also be interested in reading replies to similar inquiries from the past. Here are 2 samples (and I'm quite certain there are more) where you can read previous discussions and save some guys some of the hassle of typing everything they said before.
2009 - http://americanlongrifles.org/forum/index.php?topic=2579.msg24861;topicseen#msg24861
2018 - http://americanlongrifles.org/forum/index.php?topic=49340.0
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Wide,flat bottom grooves and very narrow lands worked for me real well back in
my shooting days.
Bob Roller
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Wide,flat bottom grooves and very narrow lands worked for me real well back in
my shooting days.
Bob Roller
That is Pope rifling. I want to try it. Does anyone currently do single point rifling to the customer's specifications?
Scot
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Wide,flat bottom grooves and very narrow lands worked for me real well back in
my shooting days.
Bob Roller
That is Pope rifling. I want to try it. Does anyone currently do single point rifling to the customer's specifications?
Scot
Bill Large made a lot of these barrels in 54 and 58 caliber.
Ed Rayl in Gassaway WV might make them now but I don't
have his contact info.I think Rice makes them for a German
customer for schuetzen rifles.
Bob Roller
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i prefer radius groove rifling. i do find cleanup is easier and little need for patched jag fouling control. not a match shooter, never will be, don't see a difference in offhand accuracy 'tween radius and flat gooves. finding a good patch/ball combination is also easier as well. ymmv, as it should be.
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i prefer radius groove rifling. i do find cleanup is easier and little need for patched jag fouling control. not a match shooter, never will be, don't see a difference in offhand accuracy 'tween radius and flat gooves. finding a good patch/ball combination is also easier as well. ymmv, as it should be.
Any experience with Rice round bottom barrels?
Seems when it comes to this, half of people are saying round bottom rifling is easier to clean, fouls less, loads easier, and is just as accurate as square bottom rifling.
But then the other half says you have to use such a thick patch and tight load combination in order to control fouling and blow by that it makes it actually harder to load, that there is no difference in cleaning, and that square bottom is more accurate...
:-\
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I use thick unbleached canvas and it fills out the deep rb grooves completely. Actually, it's just a matter of finding the load your barrel likes.
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i prefer radius groove rifling. i do find cleanup is easier and little need for patched jag fouling control. not a match shooter, never will be, don't see a difference in offhand accuracy 'tween radius and flat gooves. finding a good patch/ball combination is also easier as well. ymmv, as it should be.
Any experience with Rice round bottom barrels?
Seems when it comes to this, half of people are saying round bottom rifling is easier to clean, fouls less, loads easier, and is just as accurate as square bottom rifling.
But then the other half says you have to use such a thick patch and tight load combination in order to control fouling and blow by that it makes it actually harder to load, that there is no difference in cleaning, and that square bottom is more accurate...
:-\
not yet with rice barrels, but i have one his kits coming, so soon enuf. i've had a number of barrels "freshed out" by bobby hoyt, .50 to .54 and .36 to .40, all with .012 radius groove rifling. me like 'em.
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I currently have 3 Rice barrels with round bottom rifling,they all shoot as good as anyone would expect. I use a ball .005 under and .018 pillow ticking,lube with spit or tracks mink oil. Never had any problems with blown patches. My .54 uses .020 pocket drill and I have it coned,but still use a short starter out of habit. I can load it with just the ramrod for hunting.
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Seems as if most prefer square bottom rifling...
I fear I’ve made a mistake ordering round bottom! I didn’t know round bottom rifling causes blown patches and so on. :'(
If you use heavier loads as many people call hunting loads, then you will need to fill those deep grooves or may have blown patches.
If you use mostly loads in the squib-load range, ie: bore size loads, ie: .32gr. in a .32, 45 in a .45, 50gr. in a .50, just about any ball and patch combination will likely work
and not blow the patches.
Like some others, I see no difference in cleaning. I would have prefered, however that the .48" bl. on my A. Verner rifle had square rifling.
I have never seen deep round bottom rifling on a round ball 'match' rifle - usually .008" to .012" and square-ish.
In retrospect, I would like to try a barrel with .010" or .012" rifling cut with the same rifling head as used in deep rifling. I am sure our tighter ball and patch combinations would shoot just fine
and that the rifling does not have to be nearly as deep as even Rice makes it at .016" normally.
It could be that poor ball and patch combinations would not work at all, I do not know. I've yet to see what I consider a poor ball and patch combination user in the winner's circle
at a BC Rendezvous match, aside the odd "women's" or "kid's" matches.
With .010" to .012" rounded bottomed rifling and a decent ball and patch combination and 60" or slower twist, depending on calibre .45 through .62cal., perhaps the ultimate shape and rate of
twist would be found. I'd sure like to try one. It would have to be .54 cal. or larger and 1 1/8" oct. or round as that is the only 'other' rifle stock I have now with easily replaceable barrels.
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Seems as if most prefer square bottom rifling...
I fear I’ve made a mistake ordering round bottom! I didn’t know round bottom rifling causes blown patches and so on. :'(
If you use heavier loads as many people call hunting loads, then you will need to fill those deep grooves or may have blown patches.
If you use mostly loads in the squib-load range, ie: bore size loads, ie: .32gr. in a .32, 45 in a .45, 50gr. in a .50, just about any ball and patch combination will likely work
and not blow the patches.
Like some others, I see no difference in cleaning. I would have prefered, however that the .48" bl. on my A. Verner rifle had square rifling.
I have never seen deep round bottom rifling on a round ball 'match' rifle - usually .008" to .012" and square-ish.
In retrospect, I would like to try a barrel with .010" or .012" rifling cut with the same rifling head as used in deep rifling. I am sure our tighter ball and patch combinations would shoot just fine
and that the rifling does not have to be nearly as deep as even Rice makes it at .016" normally.
It could be that poor ball and patch combinations would not work at all, I do not know. I've yet to see what I consider a poor ball and patch combination user in the winner's circle
at a BC Rendezvous match, aside the odd "women's" or "kid's" matches.
With .010" to .012" rounded bottomed rifling and a decent ball and patch combination and 60" or slower twist, depending on calibre .45 through .62cal., perhaps the ultimate shape and rate of
twist would be found. I'd sure like to try one. It would have to be .54 cal. or larger and 1 1/8" oct. or round as that is the only 'other' rifle stock I have now with easily replaceable barrels.
I see. The only animals Id be hunting would be squirrels and rabbits and for plinking I always prefer a lighter load anyway.
Domyou guys think I should ring TVM to change to square bottom rifling?
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Do you guys think I should ring TVM to change to square bottom rifling?
I think you should quit trying to build a gun by committee and let TVM get on with building the gun. What if they have already ordered your barrel and you end up sticking them with one they will have to keep in stock until someone else requests one. Gunmakers hate those who waffle during the process.
Asking for "opinions" is not a subjective way to get facts. You only get personal preferences. It's kind like the current political situation.
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Either will be good. It’s not a bench rifle or chunk gun. You’ll figure out a ball/patch/lube combo that works great. Otherwise nobody would offer round bottomed rifling. Obviously it works. Like Dave said, preferences.
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Do you guys think I should ring TVM to change to square bottom rifling?
I think you should quit trying to build a gun by committee and let TVM get on with building the gun. What if they have already ordered your barrel and you end up sticking them with one they will have to keep in stock until someone else requests one. Gunmakers hate those who waffle during the process.
Asking for "opinions" is not a subjective way to get facts. You only get personal preferences. It's kind like the current political situation.
You are right, and I’m sorry if I offended you or anyone else. Thank you for your time and help!
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Either will be good. It’s not a bench rifle or chunk gun. You’ll figure out a ball/patch/lube combo that works great. Otherwise nobody would offer round bottomed rifling. Obviously it works. Like Dave said, preferences.
Yes I bought the gun specifically for offhand shooting and small game hunting.
Guys what I’m learning with this hobby is that for every guy out there doing this, there’s another way of doing something. What one guy loves the next guy hates, etc. but it’s the same with nearly all hobbies and makes things fun! Sorry for being a pester guys, I know I’ve been asking too many questions lately and will take a hiatus from this board as I don’t want to wear out my welcome or rock the boat.
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Smokey, I do not think that you have "offended" any one. But, you have many opinions posted to help you out. We cannot tell you how to build your rifle, however. You need to read the opinions, and take what you want from them, and build YOUR rifle to suit YOU.
I am currently building a nice rifle. Originally, it was to be a reproduction of Herman Rupp's beautiful 1793 rifle. But early on, I realized that building that reproduction was beyond my current capabilities. Sure, I asked for a few opinions, we all do. And no one is terribly offended if we do not opt for their particular opinion.
So, I am building this rifle to suit ME. And I am sure making mistakes as I go along, and that is OK - I learn from them, and when I build another rifle, hopefully I will be able to avoid those same mistakes, and probably make a host of other mistakes! There are, well, I was going to say, "none of us" who has not made mistakes, and then I remembered Mike Brooks. So, 99.9% of us have NOT made a mistake. He is the odd ball that never has.
Build your rifle, have fun doing it. And when it is done, you will have really accomplished something that les than 0.001% of the population has done, and you can take pride in it! Go out and shoot it, kill a whole ream of paper, and maybe a squirrel or three.
And we are all here to help, to advise, each other.
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You are right, and I’m sorry if I offended you or anyone else. Thank you for your time and help!
I doubt that you offended anyone, but have TVM build the gun you want, not what everyone else thinks you want. Don't 2nd guess yourself. Spend some time using the search function and do your research. Regardless of what you choose, it'll be your gun and once you learn how to feed and shoot it, you'll be happy with it. It's hard to dampen enthusiasm but sometimes it leads to needless indecision. No reason to leave the forum......just relax a bit.
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__note that I started this reply before the last several posts were up__
Do you guys think I should ring TVM to change to square bottom rifling?
I think you should quit trying to build a gun by committee and let TVM get on with building the gun. What if they have already ordered your barrel and you end up sticking them with one they will have to keep in stock until someone else requests one. Gunmakers hate those who waffle during the process.
Asking for "opinions" is not a subjective way to get facts. You only get personal preferences. It's kind like the current political situation.
As a professor of mine used to say about the law: You pays your money and you takes your chances.
I agree with Dave here to the effect of if you keep pecking at your TVM order, you're sure to get something those fellows are sick of and just want it out of the shop. Don't do that to decent gun-making folks or to yourself (it may land your gun on the "special needs" category delaying delivery). Pays your money and takes your chances.
Just never forget that no matter what ball or patch or bore or rifling or steel or lube or powder/prime or flint/cap your lock and trigger you gun winds up being constructed with, YOU yet have to develop a load for it. And your load won't be exactly the same as anyone else's.
Unless you copy cat someone else's load and "hope" it works. It might work if you can get it down the bore, or it could fall in. But it won't be optimized for accuracy and best performance available from your gun. Loading procedures tend to be different, lubes tend to be different, patches, etc. are different, as are the machining tolerances that allow some variation between moulds and bores actual sizes when measured past their nominal designations.
It's too easy to "think something to death" and come up with conclusions in theory that do not work, or do no work well in application. But it's great to learn of the most common options and variations and opinions in practice. That way if process X doesn't work as you thought it might, you can jump right to Y and see how you like that. It should come together in a way similar to others, but not quite exactly.
Just don't get your mind all made up before you're ramming balls and looking for patches and making holes in paper.
Hanshi hits the bottom line here: I use thick unbleached canvas and it fills out the deep rb grooves completely. Actually, it's just a matter of finding the load your barrel likes.
There are a lot of paths to finding those loads your bbl likes, and you can't do it online, but that's what has to happen for best satisfaction of any shooter who cares to land their bullets near the x.
I spent too many hours developing loads for moderns in order to extract best safe accuracy, it's actually somewhat simpler with BP. But so much more fun. So do that. Have fun, and trust your maker.
You can always choose another maker for your next one, after you know much more about what you want. ;)
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Well said Wade and Hanshi.
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Domyou guys think I should ring TVM to change to square bottom rifling?
I still prefer flat bottom rifling but the Rice 32 with radius rifling would shoot one jagged hole from a rest at 30 yards. That's as good as I can shoot but it might have done better with experienced younger eyes shooting.
My Rice 54 38" hunting rifle also has radius rifling (bought the components from someone that never built the rifle) and it shoots very good when I do my part but I don't think it loads or cleans any easier than the flat bottom rifling on other rifles I own and those barrels were much cheaper than the radius rifled barrels.
Dennis
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Shot my 45 cal RB barrel again. I really hate it. I can not do any better than about 3" @ 50 yds. Bench rest of course. That is not acceptable to me.
The bore is .450. The grooves are .016. Lands and grooves are about 50:50 for width.
I have tried multiple powder charges and lubes. I have tried .433 and .440 balls and patches up to 0.033". I need a steel range rod to load tighter combinations. It is my opinion that I am not getting sufficient compression the middle of the grooves with any load that does not distort the ball so much that it sours accuracy.
Before I scrap the barrel, does any one have any loads that have shot decent in such a barrel? ...Decent is under an inch at 50 yards.
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any load that does not distort the ball so much that it sours accuracy.
That is a quote from your last sentence. Why are you concerned about distorting the ball? Ideally, you must have the weave design of the fabric of the patch engraved HEAVILY on the whole perimeter of the ball touching the bore. That is not distorting the ball...it is paramount to top performance from that barrel. Even in a Toenjes .60 cal barrel with groove depth of .026", I get one hole groups for five shots at 50 meters, bench rest. .60 cal bore, .026" grooves, .595" ball and .030" (crushed) denim patches...loads with hickory ramrod.
Don't give up. If you have to use the steel range rod, so be it. At least until you ring out the accuracy potential of the barrel. The crown of the muzzle is critical to accomplish this kind of loading.
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I might humbly add that your barrel will surely shoot like a champ if you keep testing, shooting, smooth up the muzzle crown and maybe try a .445" ball. I use canvas duck and unbleached heavy canvas with excellent results. Whatever your barrel ends up liking is what you should use.
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By "distort" I mean mashed to a non round shape, not the fabric imprint. I can try some larger balls and a thinner patch. I suspect that it will make the gas blow by in the grooves worse, not better. Anything is worth a try at this point though.
I suspect the concept is fatally flawed. It has a .450 bore and is .482" in the grooves. The lands are wide. The lands being so wide makes a loadable patch ball combination that is snug in the grooves near impossible. OK for a trail walk or deer rifle, fine, but not a target rifle. It depends on one's idea of what accuracy is. I'll try once more, then I'm done.
Later I did some math:
(https://preview.ibb.co/eMuCKU/table.png) (https://ibb.co/g9wgDp)
On the shallow rifling rifle, the difference between the L/G is much less thus getting a seal is easy on both the lands and grooves. The rifling is plenty deep to spin the ball. No issues with blow by and cutting the patch in the corners of the rifling.
OP's question? I would not order another deep groove round bottom barrel.
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hanshi,
What is the thickness of your unbleached canvas and where do you get it? Also, do you wash the sizing out of it before you use it? Thanks and hope this will help all trying to work up that best load.
elkhorne
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Well it’s a shame this is being difficult. A good barrel should not be super finicky. Neither should a good lock.
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Hey guys: The most famous barrel that I ever rifled had oval bottom grooves rifled to .035" and they were twice the width of the lands. The patch was heavy sail cloth .032" and the ball was .020" undersize of the bore. It would shoot pretty much any charge of powder. But the secret was - no ball deformation! Not even imprinting the fabric weave on the soft lead. A deep muzzle crowning is also a must. Hugh Toenjes
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"and they were twice the width of the lands."
And that is the difference! When the grooves are deep and narrow it is an unsolvable problem. Every time I go to the range to try to find a load it costs me over $50. I am cutting my losses. Just now I ordered a new barrel.
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Scota4570, did you get my PM?
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Scota4570, did you get my PM?
Reply sent.
Scot
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Like the C&W song says, "Round bottom girls make the world go round."
No reason why it can't do the same for your rifling.
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Bit of a misquote Dave: "Fat bottomed girls you make the rockin' world go 'round!"
I'm sensing that Scota4570 is frustrated! I don't blame him. I feel for ya guy. Nice scientific evaluation of the situation, I might add.
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Bit of a misquote Dave: "Fat bottomed girls you make the rockin' world go 'round!"
That's why I only listen to talk radio. I can never understand the lyrics in most songs, so I make up my own. :-X
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The canvas, elkhorne, is by my measurement about .024". Squeezed in calipers it runs about .030". The way I measure with the caliper - don't have a micrometer - is to take both hands and squeeze the jaws with everything I have. It's even thicker than canvas duck, which I like and use in certain guns. Odd thing is that it seats easier than smoother, thinner material such as mattress ticking and even the duck.
I've had it for around 18 years and have used it from time to time but started using it in some rifles a good while back. Canvas duck and ticking both get used a lot in a smoothbore and certain rifles. I don't know where she got it and the original purpose was to protect walls in a small gym.
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hanshi:
I suspect the "duck" you are referring to is actually Army Duck.... a very different weave then "cotton Canvas duck." Regular canvas duck is a Fairleigh open coarse weave but is available in a number of different ounce weights. The Army duck is a more complex weave and is also available in different ounce weights.
When we made tipis and tents we used a 10.38 oz treated army duck fabric that also had sizing in it. It was quite water repellent. Much more so then cotton duck.
A good friend who shot a lot of trade gun stuff back in the day took a couple of strips of this material and washed it well to remove the sizing and then cleaned it (as in dry cleaning fluid) and used it in his trade gun. He said it was the best patch material he had ever used......
I suspect one could find untreated army duct material at large canvas supply houses but I am not sure how big an order would have to be. We bought it in 300 yard lots (36" wide) in bolts of 50 yards. That would darn sure be a lot of patches.
Modern pillow ticking which I have sitting next to me measured as you do comes out to be .009.
Just some thoughts
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Final thoughts from me on this subject:
The guys having positive results with RB rifling seem to be using larger calibers. Larger ball = more mass = more momentum. It has more ability to resist forward moment than a smaller ball. Lead is equally soft regardless of caliber. So, upon ignition, the larger ball slugs up better than a smaller one. This compensates for the deep narrow grooves. So, accuracy is sufficient despite the RB rifling, not because of it?
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Any experience with Rice round bottom barrels?
Seems when it comes to this, half of people are saying round bottom rifling is easier to clean, fouls less, loads easier, and is just as accurate as square bottom rifling.
But then the other half says you have to use such a thick patch and tight load combination in order to control fouling and blow by that it makes it actually harder to load, that there is no difference in cleaning, and that square bottom is more accurate...
:-\
Experience with Rice round bottom barrels? Yes, 38" B-weight .50 caliber. It's my deer rifle and off-hand match and woodswalk rifle. I load it with 65 grains of 2F, .490 ball, .018 patch. Spit for lube in matches, wonder lube for hunting. Not hard to load and doesn't foul up. It shoots more accurately than I can hold it. Count me in the first group.
This discussion reminds me of the Miller Lite commercials with the chants, Tastes Great! Less Filling!
-Ron
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Hello all! Another question, here. :)
What do you folks think about round (or radiused) bottom rifling for gun barrels?
1/. I’m hearing some say they’re easier to clean at the end of the day, and 2/. that they can allow more shots before needing to swab the bore, and things of that nature. 3/.As far as accuracy goes some of the top barrel makers claim between it and square bottom rifling any difference is so small as to be meaningless unless competing at the national target shooting level.
Any truth to any of this? That sure sounds good to me as far as the benefits go. I’m mostly interested in an offhand shooting and small game hunting gun for my .40 caliber. I have picked a swamped 42” round bottom rifling barrel by Rice for the TVM order I recently submitted. Hoping it was a decent choice and just gathering more information on the subject.
Thoughts?
1/.I have not found easier cleaning - but - I only have one rounded rifling barrel, all the rest are and have been square bottomed.
2/.I shoot all day with both styles of rifling - NEVER have to wipe during shooting, whether 20 shots or 100. Loading the next shot is always the same.
3/.I have no experience with a cross-test - but note, "unless competing at the national target shooting level" - shows if wanting (REAL - not just good enough)accuracy, the rounded rifling is not the way to go-
admitted by some of the top barrel makers
So - there ya go. Your mileage might vary. How many guys here with comments in this thread actually tested to get the best accuracy out of their barrels, or merely
chose a load or powder and patch/ball combination and shot that & it was accurate enough, so done?
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i prefer radius groove rifling. i do find cleanup is easier and little need for patched jag fouling control. not a match shooter, never will be, don't see a difference in offhand accuracy 'tween radius and flat gooves. finding a good patch/ball combination is also easier as well. ymmv, as it should be.
Any experience with Rice round bottom barrels?
Seems when it comes to this, half of people are saying round bottom rifling is easier to clean, fouls less, loads easier, and is just as accurate as square bottom rifling.
But then the other half says you have to use such a thick patch and tight load combination in order to control fouling and blow by that it makes it actually harder to load, that there is no difference in cleaning, and that square bottom is more accurate...
:-\
You will likely not notice a difference if you shot both side by side and if you did, you'd be splitting hairs. Most people will say they prefer whatever they have or make up a reason why they prefer one if they have both.
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You're probably correct, Huntschool. It's been a while since I bought any and the only thing I seem to recall about it was the words "cotton" and "duck". I have no way of knowing which one I bought. I do know that the unbleached canvas really does well in my rb barrels. I have a quantity of "mattress" ticking which is quite a bit heavier than pillow ticking, of which I also have a supply. With several different materials for patches, I guess I'm set up for about anything. 8)
The two Rice rb barrels I have are a .32 transitional barrel and a "B" weight .50. I can no longer shoot/see well enough - retina defect in my dominate eye - to compare the round vs square groove bores.
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I think i read through all the responses but didnt see if round bottom or flat was used historically.
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bnail: More on the round bottom rifling - I have been hand rifling barrels for 35 yrs. now and for the last 27 yrs. have been proofing every barrel that I rifle, not for strength but for accuracy. Some years ago a fellow came to me with a rifle that would not hold a group at 100 yds. so he claimed. I took the barrel off of the stock and put it on my proofing bench to see if his story was correct. It had , so called , round bottom rifling in it. After I spent the entire afternoon putting every load that I had available to me through it - I proved that he was right. No group smaller than 8" at 100 yds. The grooves were .012" deep. I told him that I thought I could fix it. So he left the barrel with me. I put it on the Rifling bench and proceeded to cut wider oval bottom grooves to about .026" without increasing the bore size or changing the twist.
The attached target was the proof target for that re-rifling. Also I lapped a slight choke towards the muzzle.
Hugh Toenjes Yes there were some original barrels that were cut with rounded bottom rifling.(https://image.ibb.co/fKODWL/img055.jpg)
(http://)
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Finally managed to post a photo -see below.
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(https://www.pyramydair.com/blog/wp-content/uploads/2015/09/09-21-15-02-rifled-bore.jpg)
Many to most were very similar to this. I have never seen a rounded bottomed rifled original with the deep grooves. Most, at least in
NA, followed this upper example.
This is an early Longrifle barrel from the mid to late 1700's. I thought it was the worse case scenario of wide land, narrow groove going, until I found this one -
below. Might be hard to find a 'tough-enough' patch, but a tick patch and smaller ball might give 'decent' hunting accuracy.
(https://www.pyramydair.com/blog/wp-content/uploads/2015/09/09-21-15-02a-rifled-bore.jpg)
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When I speak of "round bottom rifling' I do NOT mean a radius profile groove. I mean that the grooves are rounded at the bottom in stead of flat across the bottom. This was usually achieved by the cutter being slightly rounded because of wear. Today's commercially rounded grooves are generally a radius designed groove. The secret in designing an easy to load and accurate type of rifling is in the ratio of groove width to land width( The grooves are at least twice as wide as the lands) coupled with depth. This has been my experience over the last 35 yrs. This is the kind of rifling profile that I put in my barrels:
Hugh Toenjes (https://image.ibb.co/dTptJ6/P1099279.jpg)
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Here is the proof target for that barrel:(https://image.ibb.co/eCVSVf/target.jpg)
Hugh Toenjes
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Hugh What were you using for sights?
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Narrow lands and wide grooves are a good shooting formula, from my reading, and your examples, Hugh.
One downside is if you don't protect the muzzle, the lands wear rapidly.
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Tom: Thanks for the input! As far as land wear goes I have never found this to be a problem even after 12,000 - 15,000 rounds.
I can see it if you load real tight loads. But with my configuration of rifling the extra tight load is not necessary.
Hugh Toenjes
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Hugh, I agree with the comment about the grooves being much wider than the lands for deep rifling to work. From what I hear your barrels WORK.
I had a round bottom barrel with narrower, deep grooves. The problem was you couldn't stuff a tight enough load down the bore to ever shove the patching outward to seal the deep but narrow grooves. It would simply never seal, giving blow-by, velocity variations, poor accuracy and fouling.
With wider grooves like yours Hugh, it appears to be much easier to fill those grooves to the bottom.
Alternately, a person could go with Colerain's option of narrow-ish but shallow round bottom grooves. I have shot my buddy's Tip Curtis rifles, and they will shoot tight groups with those Colerain barrels. Easy to load and seal for sure.
All of that said, I have found Green Mountain square bottom rifled barrels to shoot like a house afire, and never seem to be fussy about the loads they'll shoot well.
In all of the discussions about canvas and heavy patching, I have mentioned before that The Minute-Men patching company sells some really, really tough canvas material (get the untreated) that I have never had burn through. Works super. I would love to know their source! :-)
Your mileage on all of my comments may vary.
God Bless, Marc
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Hugh,
I find it very interesting that in the above photo, you used a .562" in a .58" barrel.
I have used this same combination for decades and it does indeed work. Yes, my old Don Getz has the round -bottomed rifling as well.
Very nice target in that photo!
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Pukka: Thanks for the comment. The undersize ball helps to keep it spherical when loading. Every time one hammers the ball and patch down the barrel the once sphere is now deformed. Any upset on the ball will have an effect on accuracy.
Hugh Toenjes
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Little Joe: I do not use sights when I am proofing I just clamp the barrel in the removeable jig and keep on shooting. I only proof for accuracy of the barrel by eliminating the human factor of holding a rifle and pulling the trigger. Hugh Toenjes