Just ordered a 20" Bushmaster 450 Bushmaster upper from Midway this weekend. It's supposed to arrive this week. Scope shopping now.
Have you tried your mag yet ? Mine will not seat in any lower I have except one. The one is a forged Engage lower out of all things. Tried on all the rest from couple different manufactures.
Of course Midway customer service being lackluster will not just exchange the mag. It has been cleaned, scope mounted and bore sighted so do not feel like undoing all of that as they require me to ship everything back, which is a joke.
Guess will have to order some from Primary Arms and not shop Midway unless have to.