Low Mass AR-15 Parts?

[halfmoonclip]

Been away from AR discussions since Arfcom disappeared. The conventional wisdom, back in the day, was the full circle carrier was much to be preferred over the half circle (Colt used these initially for civilian sales, as it wouldn't cycle an autosear). The greater mass of the full circle carrier was the benefit.
My M16A1, which the gummint was kind enough to loan me in 1970, reputedly weighed 6.5 lbs, and worked all the time. The semi-only replica, built of NOS Colt parts, should weigh that too.
For the OP, how light would make you happy?
Moon

 

[David Hoback]

Been away from AR discussions since Arfcom disappeared. The conventional wisdom, back in the day, was the full circle carrier was much to be preferred over the half circle (Colt used these initially for civilian sales, as it wouldn't cycle an autosear). The greater mass of the full circle carrier was the benefit.
My M16A1, which the gummint was kind enough to loan me in 1970, reputedly weighed 6.5 lbs, and worked all the time. The semi-only replica, built of NOS Colt parts, should weigh that too.
For the OP, how light would make you happy?
Moon

Full circle vs half? Im thinking you’re referring to the difference between M16 carrier & AR-15 Carrier? “Full Circle/Half Circle” Never heard it like that… I like it But yes, the M16 carrier is far more desirable. I honestly don’t even care about it being full auto. It’s just the CORRECT Bolt Carrier. I’ve used only M16 carriers in every AR I’ve ever built since 2006. And there have been uhh… a few.

BTW: ARF.com didn’t go anywhere. The Admin received notice of a terms of service being broken on during a week, and the following Monday Godaddy shut them down with no warning & no recourse. They already had the domain AR15.com set up & ready to go. To which they changed server sites and that was that. At least that’s the story they gave. I believe something else was a bit more nefarious was going on.

 

[N555]

Woke technocrats tried to cancel arfcom.

 

[halfmoonclip]

David, you are correct about the M16 full circle carrier vs the AR15 half circle. Being incompatible with the auto sear in an M16 was the rationale Colt used. They went to a lot of trouble about avoiding interchangeability; you no doubt recall the offset/oversize pins for the upper/lower, and the oversize pins for the action parts.
All of the current BCGs I've seen for sale of late have been the full circle sort, and the oversize pins are no longer an issue.
Oddly, picked up one of the Brownells 16" retro carbine uppers, (rifle length gas system, with the gas block really close to the muzzle). It runs just fine on the NOS BCG from the M16A1 replica (full circle)...it wouldn't run with a generic full circle BCG. Ran across an older Colt half circle BCG at a gunshow, and it runs just fine on that as well.
Go figure.
Moon