are you using factory ammo? or are you handloading your own? I have one that im goingt to load for and am looking for some loads that people have tried
My load that I have worked up to:
Hornady 150gr FMJ
15.5gr Lil'Gun (started at 14.4gr I believe)
Remington 7 1/2 primer
Mixed brass (formed from damaged 5.56/223)
2.065" OAL
I could go a little hotter but it cycled my 9" AAC pistol just fine and accuracy testing with a pistol doesn't work the best
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Get a case gauge (LE Wilson works) as you will need it to form cases.