Stevens 200 trigger problem

I have a friend on a hunt in OK right now that contacted me last night with a problem he is having with his 223 stevens
Kind of has me stumped!
Factory 223 rem
SSS competition trigger

The problem as he described:
Gun functions and shoots fine when single loading
When he loads the internal box mag and bolts one into the chamber trigger will not fire
He said safety was still movable to all positions, just that the trigger would not move
So he takes the rounds out of the mag and loads another singe rd and it will fire
Any thoughts as to what the problem might be?
Thanks in advance
Jack

sounds like it might be in a bind somehow,have him take it out of the stock and work the bolt back and forth and watch trigger sear,with no round loaded.

After talking more with my buddy, it looks like the safety is out of adjusment which makes a lot more sense than the the mag being the problem
thanks for the input josebd

Jack