1. Check out the Hot Deals section of the Marketplace forum to view and order an official Mossbergowners.com hat.

New JM Pro 22” - Here we go!

Discussion in 'Mossberg 930 Autoloader' started by Sinewavz, May 28, 2019.

  1. Sinewavz

    Sinewavz .22LR

    Messages:
    13
    Good day everyone! Thank you to the admins as I am new to this site. Thought I would share my findings & mods with everyone here for current members and future ones too.

    First off, I’m happy as a clam. Just brought home a new Mossberg 930 JM Pro 22”. Local shop added some lube, and put 150 rounds of Remington Small game load #6/1oz thought it to break it in, before I brought it home for its first cleaning.

    Jerry Miculek has a great video to follow:



    During this process I thought it would be good to test and show how dirty the piston and tube spacer can get and if an aftermarket piston and tube spacer could improve on this.

    I will post my finding here and keep it updated as I go along. Mind you, I travel for work so I won’t be always testing...but when I am home let the fun begin.

    Here are pics of what my piston and tube spacer looked after first disassembly:

    [​IMG][​IMG][​IMG][​IMG]

    Cleaned everything up and gave some things a polish for a perfect start:

    [​IMG]

    Cut out some grip tape:

    [​IMG][​IMG]

    And done. Notice tape on stock grip, and Nordic rail:

    [​IMG][​IMG][​IMG][​IMG]

    Things to come:

    A SBE Precision Follower and End Cap extension are on their way. Going to get the piston after I put this stock one through some paces.

    Holding off on the Or3Gun stuff for a little too. Really want to see how this performs.

    New lifter on the way from Mossberg and sending that off to C-Rums or may check out a coupe shops here locally...want to get the loading port opened up more.

    Well thanks for looking and looking forward to the results. May take some time but patience is a virtue.



    Sent from my iPhone using Tapatalk
  2. meanstreak

    meanstreak .30-06 Supporter

    Messages:
    2,469
    I like that grip tape. Nice add on.
    Sinewavz likes this.
  3. Jmm14534

    Jmm14534 .270 WIN Supporter

    Messages:
    205
    Looking good. Keep the updates coming Sinewavz!!
    Sinewavz and meanstreak like this.
  4. Sinewavz

    Sinewavz .22LR

    Messages:
    13
    Thanks Jmm. Will do.

    Just ordered the Multi-use MST w/ Teflon, the CFR Anodized for twin/quad loading, EBR Tactile, and the sight Saddle optic from Or3Gun. Not going to install the MTS till I put the stock one thru some paces, then swap, and then make my own mods to the stock and see how they all compare.

    Also ordered the HiViz TS1002 to see if I can use it as a rear for now. Ideally, I would like to keep the front bead sight for clays, and swap to a RDS on the side saddle for Open Comp. So stock bead with HiViz rear for tactical class, then swap it out to the saddle w a Venom or Burris RDS on it for Open class.

    Right now, I’ve been searching around to find someone locally (San Diego, CA) to open my loading port more...hence the CFR from Or3Gun. Wanted to get that part before I did the loading port mod so it will be fitted perfectly.

    Finally, sending out my Lifter for welding later this coming week to C-Rum unless I find anyone (again locally).

    Really, the reason I am doing this is because I could not google enough info on mods, and what the outcome was for each mod to the JM Pro. Little bits here and there but not enough. So for those that own, or are looking into a JM Pro, please feel free to post here.




    Sent from my iPhone using Tapatalk
    Last edited: Jun 1, 2019
    meanstreak likes this.
  5. Mr.jetski

    Mr.jetski Copper BB

    Messages:
    6
    Other updates you may think about ...
    You will need to update the bolt release pivot pin - it will break
    I also radiused the shell lock lever to feed more reliably


    Sent from my iPhone using Tapatalk
    meanstreak likes this.
  6. Sinewavz

    Sinewavz .22LR

    Messages:
    13
    Have any pics of your shell lock lever mod? Love to see it.


    Sent from my iPhone using Tapatalk
    meanstreak likes this.
  7. Sinewavz

    Sinewavz .22LR

    Messages:
    13
    Had a little time to test and adjust a couple things lately. Received a bunch of things and wanted to throw them in but I held back....one thing at a time.

    Installed the SBE extended end cap (+1) with the stock follower. Loaded it up (dummy rounds) to check capacity/spring issues and zero issues. Now I’m rolling 9+1. Good add.

    Was going to wait on the SBE follower, but I ran into a double feed during dummy round reload practice. The stock follower was catching on the bolt release, also causing the bolt release to angle.

    [​IMG]

    This was fixed when I swapped out the stock follower for the SBE one. There was an obvious size difference but it fit beautifully and still 9+1.

    [​IMG][​IMG][​IMG][​IMG]

    Now that the bolt release button was straight, I could add the Or3gun tactile one. Fit perfectly, and easy to install. One screw and they provide the hex tool with it. Perfect! Another good add.

    [​IMG][​IMG][​IMG][​IMG]

    Oh yeah...and swapped the Forearm retainer out with the Or3gun double/quad anodized one. The stock one, as most people know is terrible...not snug at ALL. It was the first thing I noticed when I held the 930 for the first time. Mossberg should have built it right in the beginning or at least have fixed it by now.

    [​IMG][​IMG]

    Also received the extra carrier/lifter from Mossberg and sent it off to C-Rums. Got there yesterday and Jeff said a week turnaround so till then I’ve smoothed out the stock lifter as much as possible without changing it. Want to keep it JIC.










    Sent from my iPhone using Tapatalk
    meanstreak likes this.
  8. Mr.jetski

    Mr.jetski Copper BB

    Messages:
    6
    [​IMG]
    You’ll notice the radii around the follower and allows full extension of the follower and spring


    Sent from my iPhone using Tapatalk
    meanstreak and Sinewavz like this.
  9. Sinewavz

    Sinewavz .22LR

    Messages:
    13
    Thanks for the visual. I’ll look into that.


    Sent from my iPhone using Tapatalk
    meanstreak likes this.
  10. nitesite

    nitesite Sheepdog Moderator "Philanthropist"

    Messages:
    5,512
    You guys have amazing skills, and take great photos.
    Sinewavz and meanstreak like this.
  11. BTAZ

    BTAZ .22LR

    Messages:
    15
    Great Job..
    meanstreak and Sinewavz like this.

Share This Page