Ackley Improved question. - Page 3

HiBC · October 25, 2013, 04:19 PM

tdoyka,Agreed!

Mr Guffey:When I built my .257 AI,I built 2.One for a friend.

After a face cut to true the front of the receiver,I lapped the lugs to balanced,good contact using a spring loaded plunger screwed in the receiver threads.When I chambered,I cut both to minimum headspace,so I could just feel the "Go" gage.

I was surprised when my friend brought me brass from fireforming with case head separations.

These rifles were Mexican 98 Mausers.

It turns out,he was single loading them to fireform without putting the rounds in the magazine.He was forcing the extractor to snap over the rim.

The extra force required to do that was "anviled up" at the relatively weak juncture of the neck and shoulder.It yielded,creating excessive head clearance.The brass separated.I showed him to use the mag for controlled round feed.No more problem.

I set my fl resize die up to just bump the shoulder enough to let the bolt close easily.I do the paper clip check routinely,for safety,but the brass stays good.The primer pockets stay tight.Six or seven loads loads or so,I get a few split necks.Then I scrap the whole 100 rds,and fireform 100 more.

October 25, 2013, 04:19 PM	#51
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,286	tdoyka,Agreed! Mr Guffey:When I built my .257 AI,I built 2.One for a friend. After a face cut to true the front of the receiver,I lapped the lugs to balanced,good contact using a spring loaded plunger screwed in the receiver threads.When I chambered,I cut both to minimum headspace,so I could just feel the "Go" gage. I was surprised when my friend brought me brass from fireforming with case head separations. These rifles were Mexican 98 Mausers. It turns out,he was single loading them to fireform without putting the rounds in the magazine.He was forcing the extractor to snap over the rim. The extra force required to do that was "anviled up" at the relatively weak juncture of the neck and shoulder.It yielded,creating excessive head clearance.The brass separated.I showed him to use the mag for controlled round feed.No more problem. I set my fl resize die up to just bump the shoulder enough to let the bolt close easily.I do the paper clip check routinely,for safety,but the brass stays good.The primer pockets stay tight.Six or seven loads loads or so,I get a few split necks.Then I scrap the whole 100 rds,and fireform 100 more.