All I can say is WOW…the quality of their FA bolt carrier and bolt is fantastic…best 130.00 bucks i ever spent on an AR. MPI tested and shotpeened…amazing quality…
I run one in my mutt gun that I shoot most often and is the gun I run my can on.
It’s a good bolt group.
I am not one to boast…but Bravo company is top rate…carrier key well staked…even gave me an extra crane oring…and a free key chain to boot
BRAVO…LOL…I love quality parts…
I received a package yesterday. 50 BCM teflon-coated AR15/M16 mags with Magpul followers. They are VERY nice mags.
I look forward to picking up a few of their bolt groups once they have them in stock again.
Yes. They don’t install them because they don’t find them necessary. But people want them. I personally don’t run the oring, and haven’t had a single water leak yet!
apparently you don’t remember the Challenger incident. I run MY o-ring.
If I start using ammo with solid rocket fuel for propellant, I’ll install an oring. 
I also bought one of the FA BCG’s from Paul. I snagged a spare bolt from them as well. It’s really nice. The fit and finish is great. It runs with boring regularity in my BCM middy upper.
And that’s how I like all my firearms - boring and predictable.