MSR Pistol Designation In Doubt?

[StoneHendge]

SH, unsure what you mean... that’s a simple statement,

The entire AR pistol industry was built upon letters and "guidance" from the ATF. Before the first ATF letter to Sig or whomever it was that said "ok, that's alright as long as it's really arm brace" was where it started. Before that an AR pistol had a bare buffer tube and maybe some foam around it. Argue that ATF letters don't mean anything and we're back to bare buffer tubes. Which I think they are still saying are fine.