I've picked an OEM BCM upper with 18" barrel and LaRue floating rail with a pinned gas block. This was a BCM built upper, it's a few years old but looks unused. I want to put in on an LMT carbine lower that I've got.
I'm unsure which buffer would be appropriate. An H3?
I'd appreciate an informed suggestion.
(My search didn't turn up anything)
TIA