Having problems feeding a model 70 .416 Rem Mag

[DAVE LANGERMAN Safaris]

Hello guys
I am having trouble getting a third cartridge into the magazine of a model 70 .416 Rem Mag Safari Express. We can put two down but it seems the magazine box almost seems too small for the third shell, but I've never had this problem with a model 70 before. Any one else encountering similar problems? Any suggested fixes.
Many thanks

 

[86thecat]

Do you know if it was a 416RM from factory or a rebarrel?
I would remove the mag spring and try loading with just follower. If 3 fit, take a good look at mag spring, some have different radius at bends and can be taller when fully compressed. Follower may also have tabs on bottom to keep from over compressing mag spring, take a look at those, follower could have gotten mixed up with another rifle somewhere down the road. With floor plate open, compress follower to see if tabs on bottom are not allowing spring to fully compress or if spring is not allowing follower to bottom. If follower got mixed with another rifle, it may be too thick or have tall tabs. Maybe try spring and follower from another magnum M70 if available?
Edited this, hope it makes sense.