MWAG19919
06-09-18, 17:20
I’m curious about building/assembling a Mk18 pistol. I wanna build a pistol lower with the SBA3 brace and mate it to a 10.3” DD stripped Mk18 upper. Older threads include a lot of references to overgassed DD 10.3” barrels with port sizes of 0.080” or more, but Brownell’s has measured the gas port size on these uppers with pin gauges at 0.070”, and they claim this measurement is confirmed by DD.
My questions concern the buffer system. Since the SBA3 I’ll be getting comes with a carbine RE, would I be good to go with a Springco white spring and an H2 buffer? Would a blue spring be more appropriate? The gun will only be fired unsuppressed, as I live in a state where NFA items aren’t allowed. Most shooting will be done with moderate .223 handloads, but I want reliability with 5.56 ammo as well.
My searches only seemed to turn up info on the older, overgassed uppers. From what I saw, a lot of people were running syrac adjustable gas blocks and A5s. I’m still pretty new at this, but I would imagine a different setup is needed for .070” and .080” gas ports. The A5 route would be additional $$$, and I don’t want to change gas blocks unless I absolutely have to.
My questions concern the buffer system. Since the SBA3 I’ll be getting comes with a carbine RE, would I be good to go with a Springco white spring and an H2 buffer? Would a blue spring be more appropriate? The gun will only be fired unsuppressed, as I live in a state where NFA items aren’t allowed. Most shooting will be done with moderate .223 handloads, but I want reliability with 5.56 ammo as well.
My searches only seemed to turn up info on the older, overgassed uppers. From what I saw, a lot of people were running syrac adjustable gas blocks and A5s. I’m still pretty new at this, but I would imagine a different setup is needed for .070” and .080” gas ports. The A5 route would be additional $$$, and I don’t want to change gas blocks unless I absolutely have to.