It also involved boosting velocity from 3100fps to 3250fps,

by passing by, Friday, May 24, 2019, 18:12 (1804 days ago) @ J.Michael

pressure from 51kpsi max to 55kpsi max (latest ammo 61kpsi), and zero, ZERO cleaing kits to US Army, and bare steel bores and chambers. AND repeating same pressure problems via higher pressure carbine system, shooting even slower bullets. The new NEW Army ammo is getting the heavier bullets back up to speed, at 3000rd bolt failure costs.

Shoot a 20", use .223 instead of NATO, use a collapsible buttstock with H3 buffer to make it suorisingly handy (or same buffer in carbine, or an even heavier 9mm buffer, which mitigates a fair amount of shorter gas system problems), and keep it wet, as in a single drop of CLP at bolt vent, bolt shank/extractor, internal rails and bottom of charging handle, whenever it appears dry and it will run 5000rds before it slows enough it short strokes and requires cleaning. Can squeeze maybe another 500rds out of it via swapping to lighter buffer when it slows.

Main problems have ALWAYS been the Army messing with ammo or gun design.