Items of primary interest to the new BPCR shooter. Loading, BP SAFETY, sources of materials, rifles, etc.
56 kodiak shooter
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Post by 56 kodiak shooter » Wed Mar 16, 2016 3:33 pm

I have a tc prohunter that appears to be keyholing, what causes this my load is 62 grains of swiss 1 1/2 f with a cast performance gas check 405

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Re: keyholing

Post by Brent » Wed Mar 16, 2016 7:10 pm

That is hard to say. I'm not familiar with that rifle. I don't know its twist rate or even what it is chambered for. Typically, keyholing is caused by things like bullets that are too long or two skinny. But there can be other problems. Does the barrel lead much? Are you sure?
I'm not from here, I just live here.

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Re: keyholing

Post by Premod70 » Thu Mar 17, 2016 6:19 pm

Gas checks and black powder don't mix very well. I'd try some plain base bullets, good luck.

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Re: keyholing

Post by Arnie » Thu Mar 17, 2016 8:15 pm

The bullets may be way to hard also .

Singleshot S.A.
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Re: keyholing

Post by Singleshot S.A. » Thu Jun 16, 2016 8:34 pm

Keyholing ( un stabilized bullet), usually comes from a too heavy a bullet (too long) for the twist rate.

Sometimes aided buy too light a powder charge.

As an example........... Traditional muzzle loaders which were mainly 1:60 (ish) twist rates, were designed to shoot patched round ball, (as projectiles go,very short).
If you were hell bent on shooting Minies out of them, then the bullet had to be very short also, which also means it was light for caliber.
When the Enfields, Springfields and Zouaffe military rifles came along they were given a faster twist (1:48) so as to stabilize a decent weighted (longer) bullet.

I agree with Premod70 about the gas checks, but also bump your powder up if the manufacturer says it's ok. Sometimes a bit more horse power will help stabilize.
If no better, I'd look for a shorter / lighter bullet.

hope this helps, SS S.A.

Lumpy Grits
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Re: keyholing

Post by Lumpy Grits » Thu Jun 23, 2016 9:01 am

Arnie wroteCOLONThe bullets may be way to hard also .
THIS- :!:

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