I believe Magpul will swap it out for a commercial size if you contact CS. Maybe a better move is to get a milspec tube, up to you...
I also thought Stag used milspec diameter but guess anything can happen. Might be worth a call to Stag. If they say it's milspec on their site they should make it right.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek
Last edited by Quentin; 04-15-2011 at 04:31 AM.