Mossberg 930 JMPro springs

[Highsider989]

Hello All:

I just reread all the posts about the JMPro. I've got a 22' 8+1

I want to try to use Nordic Components Mondo Extendo mag that will give me 13+1. I have it and have installed it but have issues with tuning.

I was talking with Nordic Components and he recommends replacement of the shell stop spring, the lifter spring and polishing of the shell catch. I was going to do the polishing but I may as well replace the springs if I'm in there. So, where do I get replacement springs? Would stock mossberg parts be best or is there an aftermarket company that someone has used and recommends?

The Nordic components extended mag should get me 13+1. If I load 13 it won't cycle by hand and the last shell is very hard to load. I do have the Nordic follower. Can this be to much spring pressure on the shell stop? Would polishing the shell stop help this? Tuning the spring has been a chore any tips or tricks would be helpful.

Stock the JMpro runs great, It will cycle anything now that I've had more than 500 shells and slugs through it, and clean and lube it properly. I would like to see if the extra load capacity makes a difference in times during stages but am reluctant to try the mondo extendo mag with out being able to cycle by hand. An equipment fault is something I really want to avoid.

I would love to hear your thoughts and suggestions. No I'm not getting another shotty, I love my JMpro.

[mpom]

Not aware of after market 930 springs, but from personal experience, have found out the following: replacement for hammer spring (which you did not ask about but might need in future) is an extra power Ruger 1022 hammer spring,

replacement for the shell stop spring can be a cut to length Glock 9/40 striker spring. Have not investigated the lifter spring yet.

Had to change the shell stop spring as the Wolff mag spring overwhelmed the shell stop spring, even with a polished and radiused shell stop.