Mean Arms' Bearing Delay System (Ad-free)
Added 2025-01-27 12:00:05 +0000 UTCMean Arms has developed probably the most refined and sophisticated 9mm AR delaying system on the market, what they call Bearing Delay. This began as an exploration into fitting HK-style roller delay into and AR, and ended up with a system using three spherical bearings to redirect chamber pressure to delay opening. The system is particularly well suited to high end competition use, where the development data form Mean Arms can be use din conjunction with different "lifters" (the equivalent of the locking wedge in a roller delay system), buffers, and ammunition types to tune the system for minimal muzzle climb and felt recoil.
Disclaimer: Mean Arms sent me this upper for filming. The lower assembly I provided myself.
Comments
But WHY is ejecting 9mm from an AR carbine a tricky proposition? Is it just me or do these look metal-3D-printed? I wish they'd just called it the steuerstueck. Lifter? That term is taken (by shotguns).
Stuart Morrow
2025-04-26 08:32:35 +0000 UTCWhen you want last-round holdopen
Stuart Morrow
2025-04-26 08:30:22 +0000 UTCVery good question! I suspect that due to the lower operating pressure vs. true rifle ammo that fluting is unnecessary. I'm also pretty certain Ian would have noticed any chamber fluting and mentioned it had any been present...
Bruce Brodnax
2025-01-28 02:47:06 +0000 UTCYou want an MP5, but don't want to look like a 1980s action-star slapping the charging-handle. So we've made you an MP5, but hidden it inside a CAR15, and then taken off the carry-handle/sight.
David T Klein
2025-01-27 20:49:44 +0000 UTC"9" is supercheap ammunition. well IT USE TO BE put it this way. there are ar's in 9 here but I'd wish for something more... iconic. kp9 I find nice but way overpriced here. actually not many options for a semi 9mm.
Guido Schriewer
2025-01-27 18:49:31 +0000 UTC@Ian: it would be interesting to hear your thoughts on how this system compares with some of the other 9mm AR systems out there. Specifically, the CMMG radial delayed blowback...
Larry Schwartz
2025-01-27 18:01:34 +0000 UTCI am tempted by this upper, but there are enough 9mm guns in the safe as is.
Wayne S.
2025-01-27 17:43:04 +0000 UTCI saw this upper on MEAN arms site and have been waiting to get one! Now I feel pretty confident that it works as advertised. Thanks Ian!
Steve Koerner
2025-01-27 15:37:57 +0000 UTCNow for a 10MM version?
Beverly Chmelik
2025-01-27 14:30:48 +0000 UTCDoes the Mean Arms gun have a fluted chamber like the HK's?
Kerwin Kerr
2025-01-27 13:05:54 +0000 UTC
