@kthomas - Got any pictures of your early production mags apart? You kind of peaked my interest here cause I'm trying to finish up a Mausingfield 6GT build today & ARC mags was what I intend to use.
Down the rabbit hole I go.
The mag pictured below is a late production ARC. As of yesterday I'm @ 160 flawless feeds through a 6.5 C ARC Nuke Xylo.
One oddity I see is that the spring bottom on the ARC mag (per ARC assembly) seams like it would bias follower to nose down.
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MDT is the opposite, follower nose biased up via spring orientation.
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I switched my spring around in the ARC & tried it. Still no issues. Does it make a difference? Hell if I know YMMV.
I do plan on picking up a few LRI followers to try with the reversed spring.
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This is with mag spring reversed. You'll see at about round 5 I get a snug bolt close. Head space is really tight on this 4th of July ARC rifle. about 1 in 20 is snug close.
Little sidetrack:
I Love this rifle. It's a No Brainier for anyone thinking of getting into something comp oriented @ under $2500.
With a Hellfire it didn't care for the factory Berger 140 LRH target, but loved Hornady 147 & 140 ELDM. Switched Brakes to a Precision armament & it now loves Berger 140 & 130 LRH.
Yesterday 500 yard
Like to give myself a little challenge. I have no Chrono on the Berger 130 yet. My best guess at 2830 & guess at wind 10 mph from 4 oclock.
Free Hornady 4dof app. 2.6 mil up & .6 mil right
Cold bore + 4 with Berger factory 130 LRH. Then shot a few craft targets.
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