6MM Arc AR15 Platform FTE/Stuck-Case

d0nkey

Resident Donkey
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Aug 19, 2025
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Images and video of issue: Imgur

Details:
Faxon Match Barrel 20"
Centurion 6.5G/6Arc Bolt
AR-15 Platform

Load:
Nosler RDG 105
25.4 8208 XBR (leftovers)
Mix of 2.245 and 2.25 COAL

Issue:
more often than not, I get a FTE/Stuck Case, I then have to use a cleaning rod to push the cartridge out by entering the muzzle. Pushing it out takes 0 force so I think it could be boltface/extractor issue.

Any thoughts? Thanks
 
Images and video of issue: Imgur

Details:
Faxon Match Barrel 20"
Centurion 6.5G/6Arc Bolt
AR-15 Platform

Load:
Nosler RDG 105
25.4 8208 XBR (leftovers)
Mix of 2.245 and 2.25 COAL

Issue:
more often than not, I get a FTE/Stuck Case, I then have to use a cleaning rod to push the cartridge out by entering the muzzle. Pushing it out takes 0 force so I think it could be boltface/extractor issue.

Any thoughts? Thanks
I have very limited experience with any sort of ARC round, so I'm speaking generally.

Assuming that all is good with the chamber, not meaning that it's clean, but that the chamber is cut properly, a stuck case can be caused by either an over pressure round or insufficient closed bolt lock time.

Either will usually require knocking the casing out with a cleaning rod or, at least, having to mortar the rifle to unstick the case.

If you are able to push the case out with zero effort, I'm thinking that you're having more of a failure to extract than a stuck case.

When this happens, have you tried dropping the bolt on the case that's in the chamber and then re-racking the bolt to get the case out? If so, what happened? Is it stuck, such that you can't rack the bolt or does the bolt just come back without grabbing the casing? Once you get the casing out, is the rim torn from where the extractor tried to pull the casing out?

If you can pull the charging handle back on the casing in the chamber and it fails to extract and there is little to no damage to the casing from the extractor, I'd say replace the extractor, spring and insert.

If there is damage to the casing, from the extractor trying to pull it out, to the extent that the extractor can no longer grab onto it, you either have a pressure problem or a gas problem. If there are no over pressure signs on the fired casings, try a heavier buffer to increase the closed bolt lock time.