PRB patch condition vs accuracy

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Lost Oki

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Took my .50 Kentucky Rifle (CVA Kit) 1-48 to the range. Shooting PRB, 85 gr. 3F BP at 50 yrds off rest. First three rds I was high, 3" group, patch were shredded. 4th rd, high left, patch looked good. Using a Soluble oil mixed 6-1, 4 yr old dried as patch lube. wet/dry patch between each shot. Shot several more with mixed results on accuracy and patch condition. Gave barrel time to cool. Tried 2 day old different patch lube (Ballistol 4-1) with opposite results, 3 good shots (4" group), with good patches, one bad = 1 flyer. Not sure why the one patch on Ballistol is chewed and burned up? Thinking I did not soak patch material long enough to get even coating? Your thoughts?
 

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How thick are your patches? That also comes into play, a patch lube can only do so much. The pic of your patches shows them pretty charred, I'd say they're right on the edge of burning up...and some of them are. How easy to they go down the bore?

I'd also ask if your powder charge is random or if you have done testing on it? It can be amazing how much of a difference 5 grains can make in group size.
 
To me it looks like you need tighter patches. Try different patch thicknesses . I use Ballistol and water in a 7-1 ratio.
 
How thick are your patches? That also comes into play, a patch lube can only do so much. The pic of your patches shows them pretty charred, I'd say they're right on the edge of burning up...and some of them are. How easy to they go down the bore?

I'd also ask if your powder charge is random or if you have done testing on it? It can be amazing how much of a difference 5 grains can make in group size.
Patch material (Dry, no lube), squeezed tight in caliper = .165 Round Ball is Hornady .490. I am thinking that the pdr charge is too high. Last time I went thru in dept testing was in Indiana prior to 2006. Usually the first one or two patches have holes but after that, no issues with 3 to 4 inch group at 100yrd. With that said, your thinking is sound, need to revisit the pdr charge. Wish I had kept notes the first time I did this.
 
Do you buy and make your own patches? Could it possibly be that the material wasn't 100% cotton (or linen) and was a blend instead? Or does it not have a very tight weave?
Have you tried loading a patched RB and then pulling it back out with a puller to examine how it looks? Much easier on a clean barrel. The patch shouldn't be cut or torn and you should see the patch weave imprinted onto the ball.
Just some ideas to try to help.
 
Do you buy and make your own patches? Could it possibly be that the material wasn't 100% cotton (or linen) and was a blend instead? Or does it not have a very tight weave?
Have you tried loading a patched RB and then pulling it back out with a puller to examine how it looks? Much easier on a clean barrel. The patch shouldn't be cut or torn and you should see the patch weave imprinted onto the ball.
Just some ideas to try to help.
Patch material is denim, label said 100% cotton and I asked the lady working there and she assured me it was all cotton. She had been watching me measure thickness on several bolts of cloth and was curious as to what in the heck I was doing. Material has been washed 3 times in very hot water and machine dried. I initially purchased 3 different samples and then came back 3 days later to buy 4 yrds of this material because it gave me best groups and performance. Know I got the same bolt of cloth because I marked it when I bought samples.
I have had to pull a patched RB several yrs ago but do not remember the specifics. Another test. Thanks.
 
Several things could be going on. If the patches were lubed some time ago, they may have deteriorated. I've had that happen with some lubes. Ballistol has been reported as one that does that on another bp board. After a couple years the force of the short starter can tear them on loading. Had some homemade tallow and beeswax lubed patches that did that. Lube at the range for each shot. Try a couple different lubes, including Crisco and/or straight olive oil before going out and buying something expensive. I have used Wonderlube slathered on the bottom of the patch and could shoot all day without cleaning. You have to experiment to see what works best for your rifle. Your unlubed cloth is probably still good to use. I use bear grease mostly now, but still use Wonderlube on a couple guns. It all depends on the rifle. Mutton tallow with a bit of sweet oil seems to work well, but still needs a bit of proving before I give up the Wonderlube. Lots of things work, just don't leave a greased patch around for more than a few months before using it.

I prefer patching material bought at a fabric store to that that bought at wallyworld. The weave seems tighter to me.

If you have fewer than 200 rounds through the gun, you might be tearing patches on some rough sections of rifling. Shoot more or wrap some 4ought steel wool around a jag, add some oil, and give the barrel 100-200 full length passes to help remove burrs. I have a CVA Mt. Rifle and shoot 70g 3F or 80g 2F and it gives sub-2" 5 shot groups at 50 with my 71yo eyes. Your powder charge is a bit stout from my experience, but each rifle has its favorite load.

If fresh patches and lube continue to tear, you might try some very fine emery cloth and your thumb on the muzzle to remove any fine burrs. Only need to make a few rotations. Again, shooting the gun more will eventually remove these. Let us know if/when you get it to perform as you want. HTH.
 
Follow up: Loaded lubed patch with RB (no Pdr) all the way down, pulled back up half way, pushed back down, pulled out. No tears, see pic.
Cloth, yes, purchased at a Fabric store. Old lube is a water sol oil I got from work to try, years ago. Worked good so I stayed with it. I tried tearing old lubed patches, pushed and prodded with dull screwdriver, no tears. Hopefully I can get to the range this week and adjust the powder charge down in 5 grain increments using the 1-4 ballistol patches. If I find a sweet spot I will then work on concentration. Wish I had kept better notes back in the day. I do have some deer tallow and beeswax mix I can try IF no luck with the Ballistol / soluble oil.
Barrel condition: I built this rifle from a CVA kit back in early 90's and have no clue as to how many RB's have gone down the barrel, only issue I have with it is the 1-48 twist. I have taken several whitetail in the past out to 70 yrds.
 

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I had the same good experience with wonderlube. Shot 70 rb from a .38 original target rifle (all the round balls I had) and last one went down as smooth as the first. Is Wonderlube still the same as original Ox Yoke?
 
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