Shoulder bump problem with ai cip mag

[LongRangeFever]

Hello,

I have started to do some ladder testing with my fireformed 338 lapua AI. My problem is that my shoulder is hitting in the CIP magazine. I have bumped the shoulder back .004 and it is still catching, although barely. My question is whether to keep bumping the shoulder back until it functions correctly or to modify the mag somehow. Also how hard is it on the brass to bump it back .006-.008"? Im using Lapua brass, and really don't want to wreck it. Any advice would be great.

 

[Buffalo Chip]

I would think you should have the magazine worked over to accommodate your brass. If you keep bumping the brass back you'll have too much head space and end up with case head separation. I've been schooling up on too much head space after I started to get some separation signs.

 

[LongRangeFever]

I would think you should have the magazine worked over to accommodate your brass. If you keep bumping the brass back you'll have too much head space and end up with case head separation. I've been schooling up on too much head space after I started to get some separation signs.

Thanks for the advice. Im going to remove a rib from the mag and go from there.

 

[ShtrRdy]

Is the interference coming from the tab on the two-front of the magazine or the internal rib that runs all the way down?

 

[LongRangeFever]

Is the interference coming from the tab on the two-front of the magazine or the internal rib that runs all the way down?

It was the internal rib. I milled one out, and it functions perfectly now.