I'm new to the AR15 format so forgive me if I don't know or use correct technical language
I have a new BM450, overall I like the rifle but I'm having feed issues. When I purchashed the rifle I also ordered one spare mag from BM.
1st issue was was mainly with the extra mag, round would not go all the way to battery, or sometmes get stuck in the mag. could only get 4 rounds in mag, fifth round would need to be forced in. Found that the extra mag had another follower in the bottom for a spacer - looked like follower for a 308??? Sent spare mag back to bushmaster for replacement - both mags are the same now.
Current issue - With the bolt locked back if I insert a new mag the round most often pops out of mag. If I close the bolt before inserting the mag the round stays in the mag. But I still get intermitent stovepipes or double feeds.
Observations: I found that if I tap the mag so all the rounds go forward I can load the mag with the bolt locked back and it seems to cut down on misfeeds. I think that the rounds get shoved back do to the shock of firing the rifle so just getting them all forward to begin with isn't a good fix.
I found that the tab that locks the bolt back after last round is contacting (hanging over) the case of the round (see photos) and can cause it to tilt up or pop out altogether. I can see where this might cause misfeeds as the following round could actually be out of the feed lips as the bolt come back to battery???
The rounds do not seem to be sticking out the back of the mag. Also, no modifications have be done to the magazines or rifle.
Anyone had any issues like this?
thanks in advance, Gary