bolt carrier differences

If it is legal to use a f/a bolt carrier in an ar why do some maufacturers say you need a license for some such as bushmaster & jp ? Do i need s/a or f/a bolt carrier if using a 18" barrel?

Yes it is legal. It is all I use.

C4

Would you summarize why?

Why it is legal or why I use them?

C4

Oops! Sorry for being unclear.

I meant, “Why do you use them?”

When I got the LMT carrier group for my house gun, I never even considered and M16/full auto carrier group, so I am curious about why I might consider one the next time I need a carrier group.

I use them, because they are the orig. design and I like the extra weight.

C4

So why does bushmaster & jp rifles require paper work on their full auto carriers? And so I should use f/a carrier in an 18" barrel?

Why does LMT, COLT or STAG NOT require paper work?

Yes, I would use a FA BCG with an 18" barrel.

C4

Don’t know that’s why I ask.

c4I Grant ,you would still go with bcm over jp tactical carrier? I read what you said about the jp tactical carrier. And the carrier from bcm is f/a? Sorry for my ignorance? I’m new at computers & ars.

Because they can. They could also require buyers to submit their pilot’s certificate, stockbroker’s license, state liquor board license, etc. if they wanted to.

Ok cool.

Colt created both the M16 and the M4 and both use M16 aka ‘auto’ carriers…it’s one of those things that makes you say hmmm.