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Old 10-14-2008, 11:20 PM
kurtz kurtz is offline
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Join Date: Aug 2006
Location: Southwest Louisiana
Posts: 172
Quote:
Originally Posted by JFettig View Post
I've been watching carefully! Those are some pretty dang good velocities, almost 1600ft-lbs. Have you made any abnormal pressure observations? What is the taper like on these cases? They look pretty straight walled.

Jon
Hi Jon,

I tried about ten different powders and the pressure indicators ranged from none to destroyed brass, nothing too un-expected, the bad end was ejector and extractor gouges if I got too carried away.....the Accurate 1680 looks to be the go to powder for a 16" barrel, none of the other powders tested came close.....

one interesting observation using Winchester primers: out of 20 rounds fired at 2,900 fps 19 primers looked pretty normal; flat spot in center, rounded edges, slight lifting of firing pin strike........the one odd-ball was so flat that you couldn't have done any better with a hammer and anvil, the brass looked good and the pocket was still tight....thin primer?

the case taper is along the lines of a .308 Winchester....comes out of PMAGS really slick and cycles great...

kurtz
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