Question

[tote4570]

Who makes a 12 gauge upper receiver for an AR-15?

[the rifleer]

I know of none. I you had a 12 gauge upper, you would need a 12 gauge lower and it probably wouldn't function like an AR, it would simply look like one and have a different mechanism to reload itself.

12 gauge is much wider than a .223, so like i said, it probably wouldn't feed though the lower.

The only shotgun i have seen that is in AR style was a .410, and i don't know if you can just buy an upper.

[Don H]

It would certainly be possible to have a 12-gauge upper as long as it was single-shot - after all, there are .50BMG single-shot uppers available. I have also seen video of a belt-fed 12-gauge upper that would either be semi-auto or full-auto depending on the lower it was mounted to.