Rear shell stop rubs elevator...

[Buddy S]

Hey guys I've owned 3 mossbergs in the past 10 years and been very happy with my 500A and first 935 waterfowl. I traded my first 935 for a nice bow because I couldn't pass up the deal. I had missed my 935 and started looking for another. I got a good deal on a 935 (only missing the mod choke) with few rounds in it. I shot the gun maybe 5% of the rounds didn't cycle. These were all 3" magnums. I later noticed the elevator rubs the rear shell stop (even if trigger group is shimmed away from it but not by much). I have searched and searched all I can find is where some have sent the gun in to Mossberg and the elevator/lifter and shell stop or bolt release assembly has been replaced. I've been temped to order the parts but that's ~$40 I'd be risking if there were no changes to the design.

I have a few ideas on how I can fix it and carefully bending the rear shell stop to give clearance MAY be my best option. I'm a machinist by trade but no gunsmith so I'm very capable of any "adjustments" or "modifications" but I don't want to take a step in the wrong direction.

Anyone have this problem know what to do to fix it? Trust me when I say this gun has been throughly cleaned (even behind bolt release assembly).

Mossberg has always been great to me but the guy I spoke to was not helpful this time.

Here's a picture in which I stole from another thread of where the binding or running is occurring. Thanks!

 

[kfran1234]

Hi, I am experiencing same thing with my 935. Occasionally after first shot, the next shell gets stuck on the front edge of the ejection port.

Is this the issue you were having?

Were you able to resolve?

Thanks.

 

[Buddy S]

Yes. Very similar problem. I thought I updated this post but apparently not...

I DID fix it and here's how:
First off, my disclaimer, I'm not a gunsmith so do this at your own risk. If something happens it's not my fault.

This may or may not be the best fix but it worked for me. 2 other friends have the same gun and both slightly rub but mine was worse. There's function fine from what I've seen. My eyes or standards may differ from yours but I am a machinist and work with precision everyday. First I throughly inspected all of the moving parts looked for any possible causes, throughly cleaned (including behind the shell stop assembly)) and lightly lube, reassembled and it still rubbed. I now understand how everything works.

If you look closely you'll probably notice the elevator/lifter is actually pushed off-center by the shell stop assembly. If not, you may not need to do this.

After all checks, measure as accurately as you can how much the shell stop bar needs to be bent.
Remove stop assembly.

Dissemble and carefully bend the amount measured. But not too far. The shell still needs to naturally pop out of the mag tube and fall into the lip on the stop.

I recommend placing it in a vise and tapping with a soft face hammer.

Before going too far, reassemble and check fit.

Repeat until you have very little clearance. Some slight rubbing should still cycle.

I've shot maybe 50 rounds since with zero issues. If you need I can disassemble mine and take pics for a better description but I recommend you spend some time slowly cycling the action and paying close attention to how it works. PM me if you have questions