Shallow Rifling or ''the Devil and the Deep Blue Sea'

[stuart cee dub]

 Over the years I have tried to get commercial rifles to shoot well and consistently with poor luck.
Most recently I inherited a nicely built kit from the estate of my dutch Uncle Charles a CVA mountain rifle with the early Made in the USA barrel .

After replacing the crummy junk lock , fixing the set triggers,bending the keys a bit  and replacing the skinny front sight with something a bit thicker I shot it at a recent match and actually did very well with it at 25 and 50 yards .So I took it to my home range for some fine tuning of the loads.

Using the same thick canvas patch and .490 swedged ball backed by 35 ,40 , 45 and then 50 grains  of 3fg off the bench , i tried the best  load at 100 yds and proceeded to shoot a 200 yard NMLRA target five times and managed to hit it three times with no discernable group whatsoever.Pending sunset halted further experimentation. I had my best luck with 45 grains at the nearer 50 yd target .It is very powder charge sensitive. That was my 100 yd load.

The patches cut at the muzzle had no burn through and were loading tight needing a ball starter to seat ,nicely marked with the rifling so the ball was taking a spin .The patch is .022 thick wonder- lubed ,the bore is a true .50 going up to .510 measured side to side from the bottom of the grooves ( so the lands are .005 I'm guessing)

The whole episode recalled an attempt some years ago to get a TC renegade to shoot which despite an unpitted barrel never grouped either not even at close range . I solved that particular problem by selling it .I've had similar problems with other renegades .It too had shallow rifling.I'm thinking shallow rifling is the devils invention.

I will say near the end of day after some 50 rounds it  misfired twice needing a second cap. Wiping the bore meant the first shot would go left but proceeding shots at the 50 yd target settled back into two inches . One group was 1.5''

I'm not overly fond of the nock -like patented breech with the sub chamber these old CVA's came equipped with .
The nipple was new .The gun really hadn't been fired much when I got it. The bore is pristine not even discolored .
Unk took good care of his muzzleloaders but never shot them much .

I'm not willing to give up on this gun it has sentimental value , nicely finished too, but it isn't consistent like my deeper grooved guns I built from scratch. The sights are nice with enough daylight around the front sight to readily see for a good sight picture.

I would have thought I would have at least gotten a group at 100 just bigger and lower .
The paper at 100 yds is 21.5'' square and hard to miss.
(I'm thinking the ball is picking up some kind of demons from 50 to 100 yds such the old germanic shooters described when the angels weren't micturating in their touchholes)

 I was thinking of trying 2F next . Then perhaps trying to get a .495 ball down the barrel with a much thinner patch.
One of my shooting buddies shoots one of later versions of the gun with the same 490 ball and it shoots well for him.
He shoots with a thick patch as well. I really would like this to shoot out to 100 yds .
 
Anyone have any suggestions ?


 
 

   

[RichG]

.495 ball maybe, and more powder. You didn't say how thick the patches are. try thicker with the .490 or same with .495.

[Hungry Horse]

I shot a Mountain rifle til the barrel was almost smooth. My only complaint was reliability. They didn’t make replacement locks back then. My loads were as follows 65 to 100 grs. 3F .490 ball 16 thousandths pillow ticking, or pocket drill, patches lubed with melted venison tallow. I think you are patching too tight.

  Hungry Horse

[smylee grouch]

More powder for sure, 70+ grains of 2f.

[Don Steele]

More powder to get reliable precision at 100 yds. Larger ball and less patch is my recipe for shallow rifled barrels.
My very best 50 cal load is a .500 ball w/ .018 (compressed) canvas "duck" material.

[stuart cee dub]

I was using a cotton Canvas patch .022 thick Rich .
I have some finer duck I can try along with more powder .

A friend once told me muzzleloaders often have ''two nodes'' they will shoot at a low charge and a higher charge .
Somewhere I have a box of .495 ball too.
Thanks for the suggestions .

I'm still puzzled why the accuracy fell apart. I thought newtons 2nd laws of motion was going to work in my favor especially with a round ball.

[Hungry Horse]

A couple more observations regarding early CVA  rifles. Although they aren’t cut rifling, they aren’t the usual import kit gun stuff, that is more like a picture of rifleing than the real thing. They were button rifled  to about eight thousandths deep. I think it’s possible that you are damaging the patching when loading. I only used patching that thick when my gun was technically worn out. Remember the old timers didn’t use short starters, and bet their lives on the gun shooting center.
 Most modern material is produce overseas and is not held to the standards they once were. Pillow ticking falls into the category with shoe buttons, and buggy whips, modern ticking is not as tightly woven as it was in the past, so when you force a thick patch down bore, damage is likely. JMO.

  Hungry Horse

[hudson]

I also had an early CVA Mountain rifle Kit I built with an unmarked barrel. It had shallow rifling’s and more than usual number of groves number as I recall. Through the years three .50 cal. have passed through my hands being purchased or built. In the early days at Friendship silhouette’s there was no doubt the velocity was way above the other two. A low hit on the bears at two hundred yards would regularly knock the feet out from under them, can’t say that for the other two. I had coned the muzzle for easier loading with a .498 ball. Load was 50 gr. and 90 gr. of 3F depending on range, patch and lube forgotten. Something to remember is the breaching on the CVA rifles. The long ¼” long hole in the breach plug with an intersecting cross drill at the bottom from the drum causes problems. When wiping the crud pushed down the barrel would plug the channel. After firing a string and wiping always pop a cap, magnum caps after becoming available were always used. I have had a few problems with some part in the lock and set triggers breaking, the breaks showed improper heat treat. . Good luck with your project.

[stuart cee dub]

The patches collected were almost reuseable ,browned but not torn at all with the grooves darkened.
I have gone to a sturdy canvas material the last few years as my go-to patch
mainly because I have a particular deep grooved rifle that would absolutely requires this canvas otherwise it eat patches for lunch .Oddly it has to use 2 f as well .With 3f it even shreds the tough canvas patches .
 
I agree with you on most of the recent patch materials available Hungry Horse .

The last batch of stripped pillow ticking would not have prevented pin feathers from migrating out of a pillow . It was both thin and somewhat porous. High drying heat and two washings helped and it still works for another round grooved rifle I have .When washed it comes to about .018 .Those I haven't tried those yet .

I also have some tight weave pocket drill at .020 to try .Maybe switching powder to 2fg might help in this case as well .

If I use more powder it seems to me the spin rate would increase (RPMs) beside flattening out the trajectory

This brings a ballistic  question to mind ...

Does a bullet fired at a faster velocity maintain the same RPMs when shot out of a gun even though the drag slows the bullet down ? And would this aid in stability beyond 50 yds ?

I know round balls don't need as much spin to stabilize not like a jacketed bullet anyway .

Why then the different twist rate barrel makers use in a given caliber ?
Some round ball guns with a slower twist need more velocity to shoot well .
(I'll deduce the twist rate when I get home tonight as the barrel isn't marked with a measuring tape and a tight patch on the jag ).

The accuracy just fell apart after 50 yds and that's what got me to thinking .
The air was hot, humid  and still so I can't blame the wind .




 


   

[stuart cee dub]

 Hi Hudson ,
This barrel came slightly coned when it came to me .I think it shipped that way actually . That is probably the other reason it didn't tear the canvas patches.

I really have nothing good to say about the crude set triggers on this rifle other than they work at the moment . The spring on the back trigger really needs to be stoned down some .

If they break I would be only to happy to use a set of Davis Dbl sett triggers. but if it isn't broke ....

The weird subchamber, I think ,was made to prevent the hammer from bending a normal threaded drum- in -the- barrel- wall.  The original lock never supported the drum the tolerance just weren't there . It was cheaper to make than a patent breech . Like any good marketer CVA touted this as a positive feature to cover a cost saving measure .
   

[Hungry Horse]

I would suspect the odd breeching of these guns was dictated by the companies insurance provider. I was present when a demonstration was staged to show what would happen if you overloaded, and blew up you new muzzleloader. They could’nt put enough black powder in it to blow it up. Even double charged, with one patched ball on the powder, and one short started, it only bulged the barrel, and blew the front sight off. It took a lot of Red Dot to blow it up.

 Hungry Horse

[hanshi]

The suggestions of a larger ball, varying patch thicknesses and experimenting with 2F are solid.  Shallow grooved barrels normally shoot quite well.  But when combined with faster twists (the bugaboo) some loads "strip (skip over)" the grooves.  1-48" is NOT a "fast" twist, but can make finding the best loads more problematic with the addition of shallow rifling.

[D. Taylor Sapergia]

In my opinion, Hanshi is on the correct course.  Your rifle will shoot best with a .495" PURE LEAD BALL, a cotton denim type of patch with the double weave as they are tougher than a single weave cloth like canvas, patch thickness .018" to .020" compressed hard in a Vernier's caliper, and a liquid lube like Mr. Flintlock or Lehigh Valley Lube, or spit.  Wonder lube does not impress me, putting it PC mildly.  A black powder powder charge of 70 gr. to 90 gr. GOEX 3Fg or 2Fg.
You should be able to get that rifle to shoot a 2 MOA group at 100 yards with loads in this neghbourhood, notwithstanding your eyesight, shooting ability, and sights.

[Daryl]

Last 2 posts hit the nail on the larger, flat circular blunt end.

[stuart cee dub]

 Got it.
I have some .495 ball on hand and some denim  that compresses to .020'' and plenty of spit and powder in both grades.
Eyes are declining but I can still see the sights very well (on this gun anyway).
I'll try it this weekend .

Admittedly I have a secret agenda ....Ultimately I would like to get my revenge on the 100yd standing bear target 


 
 

[Daryl]

Got it.
I have some .495 ball on hand and some denim  that compresses to .020'' and plenty of spit and powder in both grades.
Eyes are declining but I can still see the sights very well (on this gun anyway).
I'll try it this weekend .

Admittedly I have a secret agenda ....Ultimately I would like to get my revenge on the 100yd standing bear target 

Stuart, about the only place that combo will not work "PERFECTLY" is in a barrel with .025" rounded or square rifling.

With a properly smooth crown along with the proper use of a short starter and rod, along with a decent powder charge, your work is done.

You may take some time discovering what powder charge to use - make sure you go past what you 'think' your top load might be.  Some guys

are just too cheap (on powder) to get the utmost from their rifles.  My TC, with .004" square rifling, liked a .495" ball and .022" denim patch with 85gr. 2F powder.

It did not shoot well with 3f in any charge and seemed to want to foul with the faster powder. 2F was the answer for that rifle's 48" twist.

[stuart cee dub]

Well I went shooting this afternoon and realized when in my rush to get to the range I left my .495 balls in the brown bag at home with my stapler . ( I keep a few push pins in my shooting box)
But I did bring my 2f.

So working with what I had I compared charges of 2f vs 3f working my way up.
I made some sight adjustments on the 50 yd target and moved out to 100 yds.

After some experimentation 70 grns of 2f yielded a 3 hole 2'' group from the bench at 100 yds.
I tweeked the front sight over a bit
then  hauled out the bear target and made about a 6'' group on that landing a bit low from point of aim .
2f , and more of it ,made a huge difference.

Snapping a cap occasionally prevented the misfires keeping the fire channel clean .This gun does not like shooting from a clean and oiled bore and requires a fouling shot before settling down .

I'll try the .495 balls and denim this weekend .I'm going to try the same combination on my flinter ,another 50, while I'm at it.
The 2f seems to be a bit easier on the shoulder and really I expected more fouling .

I wasn't able to accurately figure out the twist, the shallow rifling wasn't gripping the patch tightly and the jag may have been rotating so i kept coming up with 1-40 or 1-37 twist It's just not that tight of a twist.

[Hungry Horse]

CVA Mountain Rifles were 1in 66” twist. My current rifle is 1in72” twist, and although I finally found a good working load for it, I would much prefer the faster twist. Not 1in48” fast, but, 1in 56” is good, as is 1in 66”. All of these recommendations are in regards to calibers .45 and larger.

  Hungry Horse

[hudson]

As I recall 1 in 66 have some reports of 1 in 60.

[Hungry Horse]

Nope, CVA’s were 1in66”. There were some barrels made in 1in60” but they were’nt CVA.

  Hungry Horse

[bgf]

The similar (but Spanish) barrel on my traditions Kentucky likes 75 grains of 2f for longer ranges.  It has been a while, but I know longer range accuracy was poor below 60 and then declining again by 90.  I don't know whether that was torn patching or because the barrel was so short it could only use so much powder efficiently....I might have just been tired by the time I got up to 90 also .  My longer .50 cal barrels seem to maintain accuracy until at least 100. 

I used 490 with thicker patch or 495 with less patch on mine, as it is pretty tight, but the ball size doesn't seem to matter that much with a complementary patch thickness. 

You need to wipe out the flash passage with pipe cleaner and preferably a little alcohol before shooting, just like the barrel, and as someone said above, the Magnum caps work better.  I always shot one primer shot at leaf after cleaning out bore and flash channel, but not after that, as it seemed to stay clear if clean and free of oil before shooting.  Hard to remember the details of caplock shooting when I get it out once a year or so, but this detail stuck with me.

I use 2f the most in all my 50s.  It kicks more gently and doesn't heat up the barrel quite as quickly, seems easier on patches also when you get to bigger charges.

[stuart cee dub]

Just to finish what was started .

The .495 ball worked well in combination with the 2f but trying to get anything thicker than .018 thick denim down the bore was a real trial. The heaviest patch really didn't improve accuracy.(If it did then I just can't hold any better to be able to discern it) .My best 4 shot group was 4 3/8''

It worked at least equally well as the best .490 ball and the heavy canvas combination using 2 fg and shot to the same point of aim .I tried pocket drill of the same thickness and got erratic patternless shooting at 100 yds .

The pocket drill recovered patches showed the firing cutting on one side. It worked great on another rifle so I thought I would try it anyway .

The denim held up well as patch material.It's not normally what I use but it's very tough .Thanks everyone for their input .