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JM Pro No Bang

Rumbleboom

Rumbleboom

Copper BB
Hello all. I am having an issue with my JM Pro. I bought it new in December. I used it a couple times and worked ok. Some light target loads wouldn't eject. Everything else worked fine. I managed to find the OR3GUN parts. I installed them a while ago. I was out this weekend to try it again and it would not fire at all, just click, I tried slugs, 00buck, and target loads. I'm sure I must have put something together wrong although I'm not sure what as it seems pretty straightforward. What should I look for when I take it apart? I haven't had time to look yet. Any help would be greatly appreciated. Thanks
 
I can't advise to if you "put it together wrong" but pics would help. A new 930/940 may require some "break-in" before it functions reliably. Refer to the Owner's Manual to see what they say. IOW, RTFOM! ;)

BTW, Welcome Aboard! :)
 
I have read the manual and watched the vids. I took it apart tonight and everything looks fine as far as i can tell. It function tests fine. I worked fine before i took it apart to add the OR3GUN parts. I'm baffled as it will not fire at all.
 
Does sound odd for sure. It's possible you overlooked something minor...I'd advise you strip it down again give it a THOROUGH degreasing. I use Rem Action Cleaner...works like a hot damn...I love that stuff. It's an aerosol degreaser and works great for getting into hard to reach places like trigger groups and bolts. What I can't wipe or brush away, I use my air compressor to blow the loosened crap out. Then give everything a light coat of oil...I blow that through with the compressor as well. Since I started using that routine, I've had zero issues with any of my firearms. The nice part is you can use far less oil and it tends to weep and seep less after cleaning and lubing.

EDIT: FYI - Rem Action Cleaner is like brake cleaner...if you know what that's like. It evaporates pretty fast, so soaking it and working it pretty fast is necessary. It does a great job of cutting grease and grime. The trigger on my 870 wouldn't go bang either at one time but was freed up immediately by that stuff. You never know how long your gun sat before you got it. You don't know how old the grease was that was used when it was assembled either. If you happen to keep it under a bed or in a spot where it's getting exposed to dust...stuff gets cruddy.
 
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OR3GUN is/was a sponsor here. Last I heard, they were still in business but maybe a little lax in replying for whatever reason such as busy, busy. I suggest you drop them a line to see what's up with your setup.

Additionally, I would try putting the old parts back in to see if the gun runs again. Start from step 1...
 
Jmm14534 said:
What Bobster said and welcome aboard. What model JM Pro?
Click to expand...
It is a JM Pro Tactical. I pulled it apart again, cleaned and oiled again. I sent it home with a coworker who has a place to shoot. He shot about a dozen shells and it worked fine. However when you use the bolt release to load the shell everything is fine but if you use the charging handle, the bolt stops about a quarter inch short. Not sure what would cause this.
 
Rumbleboom,
Glad you had some partial success a least. You should be able to load successfully both ways. 90% of the time I use the bolt release button. When I do use the charging handle I pull it all the way back, let go and just let the spring do the rest. It works on my M930.
If you bump the charging handle forward when it gets stuck does it seat the shell? Are there any marks or scratches on the shell or brass that may indicate where it’s getting stuck?
If you have some 12 gauge dummy rounds then try and see if they work. Maybe it’s a break in issue. If you are using live ammo make sure the safety is on, trigger finger is outside of the trigger guard and the barrel is pointed in a safe direction. If it’s not fat brass then maybe the chamber needs a real good cleaning. I don’t think it’s a dimensional issue since the bolt release buttons works fine.
Post a pic of the stuck shell.
 
Jmm14534 said:
If you bump the charging handle forward when it gets stuck does it seat the shell? Are there any marks or scratches on the shell or brass that may indicate where it’s getting stuck?
Click to expand...

I was thinking this same thing too. Maybe the chamber is a little "tight"? I've known people to "polish" the chamber with good results.
 
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