Flush fit ai mags?

This is the only one I know of. 3.625 internal.

 
This is the only one I know of. 3.625 internal.

That’s actually kinda cool!
 
Accurate Mag makes 3 rounders in 3.715" and 3.850"

 
Accurate Mag makes 3 rounders in 3.715" and 3.850"

I have the CIP going on a 300 prc that’s being built. Fits the bill and it doesn’t hang lower than the trigger guard so I was ok with that.