bullet stability
I have heard stories of this with the .50 BMG round also. I can not verify any of the rumors, but I have heard that you need at least 300 yards to fully stablize the bullet.
I have had problems with my .300 stablizing 240 sierras at 25 yards. I even pushed them up to 1200 fps and they still keyholed. My gun is supposed to have the 1 in 8 twist.
This is an interesting theory, and I will have to try some extended range firing to see if there is any difference.
The 220 corbon load does stablize at 25 yards in my gun.
The other thing you might try is using a slower powder. My own personal theory on that is that a slower powder may affect the bullet differently in the barrel, and may stabilize the bullet better. I have not tried this myself yet, but am planning on it.
I suppose that you should also look at what is on the end of your barrel. I have an A2 flash hider. A muzzle break or silencer may affect these bullets differently, as if they are, as I suspect, barely stable, a small variance as they are leaving the bore could throw them into a tumble.
Also, the trueness (I hope that's a word) of the break/flash hider hole, to the hole in the bore, will make a difference.
In regular rifle stuff, this probably would not been seen until you are at longer ranges, but with the slow speeds of the long heavy bullets, it may not take much to throw them off.
An interesting question is, even though they are keyholing, are they holding a good group?
I doubt if they are not grouping at short range, they probably will not group farther out.
However, if they are holding a decent group, but keyholing, they may be hope.
These are awfully heavy, long bullets at very slow velocities. It may take a little voodoo to get them to work right.
Joel
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