M41 magazine tuning

any info online on tuning M41 mags.  I have one mag that loves to jam on the 3rd round.  My other mags work fine but they all seem to hold the bullets a different way.  On some the lips are a little snug on the bullets on others no tension on the bullets at all.  When I say bullets I mean the lead projectile not the case

Thanks all

Joe

Sounds like a spring problem. But cleaning might help. I have never seen a 41 mag that needed adjusted. I suppose it could have nose dived on a cement floor sometime. FYI. They are inexpensive and available.