Bolt won't pick up the last round from the magazine?

The rifle in question is a Stevens 200 centerfeed rifle. It was originally a .223 Rem it's now a 6mm-222 Rem Mag, and it doesn't matter if it's the only round in the magazine or if I've loaded four down the last cartridge won't strip from the magazine. The bolt just rides over the top of the cartridge. The cartridges strip just fine with more than one cartridge in the magazine.

I can't see what the problem is when I had the action out of the stock. The magazine seems to be properly seated in the well, and my action is making even contact with the pillars. Should I be thinking magazine spring and follower or something else?

Make sure the mag follower put in the stock in the right direction
Try stretching the mag spring a little
Last I would try adjusting the mag lips--a little bending changes a lot so go slow
Jack

I'll take a look at it after pronghorn season is over, I don't think it's going to affect my hunt. I shattered my leg last year and didn't use rifles I had to reload for after my ammo supply ran out. I wasn't able to stand on my leg at the bench much, and it took a full year before I was able to return to work. I was so focused on getting back to work that I lost track of things and hunting season crept up on me, at least I only have one season to worry about my only other hunt is a ML deer hunt.