Newbie AR questions

[eastwood44mag]

Yes, they're greenhorn questions, I know, but please don't laugh:

1.) Aside from .308, do any other available cartridges require the larger receiver?

2.) Can any parts interchange between the .223 and .308 receivers (if so, which?)?

3.) How is a stripped receiver registered when it is made (i.e. since it has no barrel, what chambering is it registered as having?)?

Thanks.

 

[RockyMtnTactical]

Any larger calibers that won't fit in an AR15 magwell need an AR10 lower, like .243, etc...

Something like 60% of parts will interchange IIRC. I don't have the time to name them all though...

You can get AR15 lowers chambered in a variety of chamberings, although that doesn't mean you cannot chamber it in something other than that. For instance most AR15 lowers are registered as .223/5.56 and some are registered as 9mm or 6.8, etc... but they are all the same dimensions...

 

[Monkeybear]

3.) How is a stripped receiver registered when it is made (i.e. since it has no barrel, what chambering is it registered as having?)?

It is given a serial number and either registered as a pistol receiver or a rifle receiver depending on whether or not it is being turned into a pistol or a rifle. It is not registered for a specific caliber. The manufacture may decide to stamp it with a specific caliber but that is entirely up to them.