AR BCG half vs. full circle (Any difference?)

[nanoer]

Hey guys, I wanted to know whats the difference between a Colt full circle Vs. a Colt Half circle BCG?

I've always wanted to know but couldn't find anything about it... might be my bad luck. Please inform me the difference.

nanoer

[glockster]

Hey guys, I wanted to know whats the difference between a Colt full circle Vs. a Colt Half circle BCG?

I've always wanted to know but couldn't find anything about it... might be my bad luck. Please inform me the difference.

nanoer

The full-circle is made for the M16 family (auto) and the half-circle is the semiauto carrier.

[ar15barrels]

1000 words:

[Sydwaiz]

I think Colt did the half circle so there is no chance that you could use a drop in auto sear or lightning link and go full auto. Without the bottom half of the bolt carrier, there is nothing to trip the sear. In a semi auto rifle, it will function no differently than any other bolt carrier unless you are worried about the weight difference.

[nanoer]

Wow thank you guys! that was a big help, I also love pictures!!!! I now know I have a sp1 BCG.

nanoer

[rbgaynor]

I also love pictures!!!!

Yep, we're very fortunate to have people like Randall here.

[bohoki]

they had to use a fully milled out bottom on the colts with the steel block in the place of the autosear it protruded above the lower deck

[ar15barrels]

they had to use a fully milled out bottom on the colts with the steel block in the place of the autosear it protruded above the lower deck

Actually, that's not the case.
The sear block stops the installation of an auto sear or DIAS, but a semi-auto carrier fits behind it just fine.

[bohoki]

Actually, that's not the case.
The sear block stops the installation of an auto sear or DIAS, but a semi-auto carrier fits behind it just fine.

hmm i stand corrected but why the heck do they chop any if it is not required by law

[Sydwaiz]

hmm i stand corrected but why the heck do they chop any if it is not required by law

Why the heck did Colt do a lot of things?