Walt I don't think mini will fire out of battery any more than an AR will. You would need primer, firing pin, disconector, and chartridge headspace problem(S) and is likely that it would fire just after lockup. This is what I gathered from M14 SHOP MANUAL.
Check out Speer reloading manual saying you can max ch 223 with 26 grains using mil brass, this exceeds all other manuals using commercial brass, dont believe everyhting in reloading manuals folks.
Sounds like you need Hk USP just shoot stuck bullet out barrel, but then again that AR ain't no Hk. HaHa