Ranger 103-2 aka Marlin 80 issue

[barnsaw]

I picked up this gun a while back, no mag. Found a mag and made it to the range today. Issue is that it will fail to fire with the magazine in, very light strike mark, but will fire fine with the mag out as a single shots. Ripped it apart farted around, could not figure it out. Any gurus have advice or ideas?
Thanks

 

[Father]

Is the mag pushing up on the bolt causing the firing pin to bind?

 

[barnsaw]

Didn't look as such, but maybe, will rip her apart and see if it slides along or impedes.