does the 556 take ar lower parts (hammer trigger etc) or do they take there own parts.
thanks
Nope. It has its own
This! I love the 2 Stage trigger in my 556. You can adjust the pull by removing the grip and adjusting the screw.
Originally Posted By C_Swimm:
Nope. It has its own
Are any of the lower parts interchangeable with the ar15. Is the lower on the 556 considered the firearm like the AR15 or is it the upper?
The mag release button is compatible with one from an AR, and maybe the detent pins and springs for the pivot pin and take down pin, but I haven't really tried so I can't be 100% sure. Other than those I can't think of anything else that may be compatible with an AR lower parts kit.
As already mentioned the upper receiver is the serial numbered part that is legally considered the firearm. The lower is actually called the trigger group on the 556. At least that is what they were calling it when they first came out. It didn't really stick though as everyone pretty much took to calling it a lower receiver anyway.
Thanks. It is interesting that the lower on the AR15 is the firearm and the lower on the 556 is just a part. So there are no restrictions on shipping a Sig 556 lower?
Originally Posted By steve0:
Thanks. It is interesting that the lower on the AR15 is the firearm and the lower on the 556 is just a part. So there are no restrictions on shipping a Sig 556 lower?
The AR is really the odd one. On MOST rifles the upper is the firearm, not the lower.
You are correct there are no restrictions on 556 lowers.
