Author Topic: Tight spot in barrel (Read 12375 times)

okawbow · « **on:** January 17, 2016, 12:42:22 AM »

Hi all

I recently bought an unused older barrel from an individual. I got it out today, and decided to check the twist and rifling depth, before deciding what type of rifle I would build with it.

I pushed a very tight fitting patch on a jag down from the muzzle, and it stopped about 1/2 way down. I tried again from the breech, and it stopped again near the center. There is an obvious tight spot a few inches long, near the center of the barrel. The rifling is new looking, and very bright, so it is not a rusty spot. There are no markings on the barrel, and I don't know who made it.

The barrel is 45 caliber, and 1" Oct. X42" long.

Can it be fixed, short of rebore? Would lapping be a possiblle remedy?

GANGGREEN · « **Reply #1 on:** January 17, 2016, 02:00:54 AM »

What were you planning on doing with it. A .45 with a 1" barrel is going to weigh a ton anyway, maybe bore it out to .50 or .54 depending on what you had in mind.

okawbow · « **Reply #2 on:** January 17, 2016, 02:15:09 AM »

I want to make a heavy off hand target rifle with it. I'm a little hesitant to spend too much money and time on the barrel, because I don't know who made it, and what the steel is, etc.

Has anyone had success lapping a tight spot out?

smylee grouch · « **Reply #3 on:** January 17, 2016, 02:25:07 AM »

I have done it and if you do, work from the breech end. Once the tight spot is gone I would continue lapping untill you have somewhat of a choked muzzle, about four inches worth. Others here will probably advise other wise but that is what I would do. A 42 inch 45 in one inch barrel will IMHO be way too heavy.

okawbow · « **Reply #4 on:** January 17, 2016, 02:59:40 AM »

What about lapping abrasive? I've read some use valve grinding compound, diamond paste, Emory flour, etc.

rich pierce · « **Reply #5 on:** January 17, 2016, 03:28:56 AM »

I think it can be lapped out but will take some time. It is also possible to freshen the lands by making a cutter inletted into the slug that cuts the lands, not the grooves.

smylee grouch · « **Reply #6 on:** January 17, 2016, 05:19:24 AM »

Some use valve grinding compound. I used three different grits in paste form from Brownells. They still sell it I think. I dont remember the grit number. I mixed some in with my shooting patch lube one time to try to polish a used barrel, it seemed to help after a couple of hundred rounds.

coutios · « **Reply #7 on:** January 17, 2016, 08:06:51 AM »

Depending on your terms of sale I'd send it back, unless you got a Reeeeelly good deal.. Once you play with it it's yours.. Just my thoughts

Regards
Dave

Captchee · « **Reply #8 on:** January 17, 2016, 03:44:05 PM »

myself i would slug the barrel so as to see whats actually going on right there . depending on just how much of a restriction is there , lapping it could be an option .
to much i and it will then depend on how much time you want to spend on it . most certainly making a larger slug and putting a cutter on it would work as well .
valve polishing / grinding compound will work just fine for hand lapping or fire lapping in a muzzleloader

rhbrink · « **Reply #9 on:** January 17, 2016, 05:04:55 PM »

I would see how much restriction that you really have there. One way to do that is to start a slug in the muzzle end and then push it back out do the same for the breech end and do the same then start another and push it all the way through. Mark and measure all three you should be able to see just how much of restriction that you have. That might help you to decide what you would like to do with the barrel? If it's only a thousandths or two then it could be lapped out but that is also a lot of work been there and done that!

RB

Bob Roller · « **Reply #10 on:** January 17, 2016, 05:18:26 PM »

Quote from: rhbrink on January 17, 2016, 05:04:55 PM

I would see how much restriction that you really have there. One way to do that is to start a slug in the muzzle end and then push it back out do the same for the breech end and do the same then start another and push it all the way through. Mark and measure all three you should be able to see just how much of restriction that you have. That might help you to decide what you would like to do with the barrel? If it's only a thousandths or two then it could be lapped out but that is also a lot of work been there and done that!

RB

That's an Arkansas choke,tight in the middle and loose at the two ends. Back when I was shooting Sharps and Rolling Block rifles a man had a Sharps 74 in 40-65 with a tight spot that leaded but it shot well enough to win.

Bob Roller

okawbow · « **Reply #11 on:** January 17, 2016, 05:34:59 PM »

Thanks, all

I'll try the suggestions and see how tight it is. A tight cleaning patch on a jag will go in about 20" from either the muzzle or the breech, and stops cold in the middle.

I bought the barrel cheap, and don't mind lapping out the tight spot.

Should I only try and work out the tight spot and leave the muzzle end alone as much as possible?

rich pierce · « **Reply #12 on:** January 17, 2016, 08:23:13 PM »

Quote from: rhbrink on January 17, 2016, 05:04:55 PM

I would see how much restriction that you really have there. One way to do that is to start a slug in the muzzle end and then push it back out do the same for the breech end and do the same then start another and push it all the way through. Mark and measure all three you should be able to see just how much of restriction that you have. That might help you to decide what you would like to do with the barrel? If it's only a thousandths or two then it could be lapped out but that is also a lot of work been there and done that!

RB

Best suggestion so far! Just in my opinion.

sqrldog · « **Reply #13 on:** January 17, 2016, 08:34:34 PM »

It almost sound as if someone at one time or another has clamped the barrel really tight in a vise. Of course it take quite a bit of pressure on an inch .45 but it can be done. Lapping will work not really hard to do just a little labor intensive. Or have it recut to a larger caliber. Going to make a heavy gun as it exists. Tim

okawbow · « **Reply #14 on:** January 17, 2016, 09:24:19 PM »

I plan on using the barrel to reproduce an old family rifle that I can't bring home as yet. It has a 1' barrel 38.5" long. Yes, it will be heavy, but most guns of that period were muzzle heavy.

photo by okawbow, on Flickr

bob in the woods · « **Reply #15 on:** January 18, 2016, 02:27:46 AM »

I know this is probably a stupid question, but......You don't have a ball stuck in there do you ?

okawbow · « **Reply #16 on:** January 18, 2016, 02:36:11 AM »

Never fired older barrel. Bore looks perfect. When I first got the barrel, I ran a patch down to check the twist. A few months later, yesterday, I tried a tighter jag with a patch. The fit on that jag is much closer to the bore size. A patch goes smoothly until, at the center of the barrel, it won't go any farther. The jag and patch combo is so tight, that even a thousandth or two would stop it.

rhbrink · « **Reply #17 on:** January 18, 2016, 03:27:33 PM »

A cleaning patch no matter how tight stopping would have me highly suspicious? There are so some electronic cameras the hook up the computer for only about 15 bucks might be worth a look? Makes me wonder if like someone mentioned that the barrel has been clamped too tight? A burr left over from the rifling process? Have you tried some 0000 steel wool or maybe some of the Scotch Bright cleaning pads? They will help remove rough spots they make me a bit nervous using something like that but it doesn't sound like you have much to loose?

RB

okawbow · « **Reply #18 on:** January 18, 2016, 05:08:29 PM »

I can look through the barrel into a bright light, and can't see anything but a perfect smooth and shiney bore. There are no marks on the outside of the barrel, either.

I'm making a lapping rig, from a 3/8" stainless steel rod I have, and will lap out the tight spot, and try to put a little choke in the muzzle.

Dave R · « **Reply #19 on:** January 18, 2016, 09:46:52 PM »

Rbrink,

Where can we find an electric camera to hook up to a computer for $15.00?

Thanks!
Dave R

ddoyle · « **Reply #20 on:** January 18, 2016, 10:12:12 PM »

DaveR. china- start with aliexpress but only use it to make contacts don't buy the garbage listed on there. Word of advice if you shop for 15 dollar stuff you get garbage but if you shop for 20 dollar stuff the quality goes way up. Just bought the wife an opthalmascope for a 100 bucks that puts the USA and German branded versions to shame, 10% the cost 100% better quality

.

Be careful though cause once you discover how available good quality tooling can be (find the suppliers that serve chinese industry and not north american wholesalers) you will have trouble not supporting those red bastards directly instead of indirectly

.

rhbrink · « **Reply #21 on:** January 19, 2016, 01:11:55 AM »

Quote from: Dave R on January 18, 2016, 09:46:52 PM

Rbrink,

Where can we find an electric camera to hook up to a computer for $15.00?

Thanks!
Dave R

I don't have one but saw where some guys were using them I think that evil bay and Amazon have them.

RB

Mike Brooks · « **Reply #22 on:** January 19, 2016, 01:18:50 AM »

I built a gun around a barrel that ended up having a tight spot in it. It shot exceptionally well.

okawbow · « **Reply #23 on:** January 19, 2016, 01:37:37 AM »

Maybe I should try it first. I can always lap it later.

Daryl · « **Reply #24 on:** January 19, 2016, 02:35:49 AM »

I believe that if you cannot shove a tight patch down the bore on a jag, you will not be able to load a ball and patch that have to be tighter yet, just to shoot with 1/2 decent accuracy, let alone shoot well.

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Author Topic: Tight spot in barrel (Read 12375 times)

coutios

rhbrink

rhbrink

ddoyle

rhbrink