attention Mossberg 930 owners

[gunsarefun]

I started having issues with my 930 not wanting to cycle cheap bird shot. Never had a problem before and with about 250 rounds down the barrel, I figured it was time for me to clean it for the first time.

I followed the manual on how to field strip my 930 SPX, for the first time. Cleaned it, lubed it, and was positive I had it put back together correctly. After test firing, I found that it would fire the first round, reload properly, but the bottom half of the bolt would not come back all the way into battery. This would leave to a "click" apon pulling the trigger a 2nd time. I would rack the action, and it would fire again, but not after reloading itself.

The problem was that the piston was too tight in the barrel cylinder. Here is the important part the manual doesn't talk about taking the piston actually apart. To properly clean it, remove the back retaining ring off the piston, then you can remove the piston ring itself. The piston is made up of 3 individual parts. A small flat head pryed in the right spot will get the rings off. You will find all kinds of carbon under the rings and on the piston itself. Once that is cleaned well, the piston will glide in and out of the barrel cylinder without effort.

I'm sure most of you 930 experts already have this figured out, but thought it would be a good sticky for the guys cleaning their 930's for the first time.

[mr_benster]

Thanks for posting. Ill refer to this post when I clean mine.

[osis32]

Ditto

[gunsarefun]

I just emailed Mossberg asking if they would revise the owners manual with more detailed info about the piston itself.

[dems4gun2]

thanks, I was about to clean my 930 spx tonight

[nitrofc]

I have to do this with my 935 I've had for years.
Got to keep her clean and lubed up good.

[Mystery Meat]

You are right about cleaning the gas piston rings. I had the same problem. Make sure you reinstall the rings in the right direction. Also, the SPX works best when it is wet with lube. Don't skimp on lube, or wipe too much of it off after application.

[a1rfreshener]

i like to burn oil out of my piston .... thats how wet i run it, and most i got before cleaning was about 200 over a two day period, before the next day id take the hand gaurd off and just put a drop of oil on the piston and shoot all day.

[speeddreamz]

I sand down the areas where there is massive buildup on the mag tube (from the piston)

A little bit of sand paper to get off the gunk and it works great now, never jams or short cycles.

[CasperSYTFU]

I sand down the areas where there is massive buildup on the mag tube (from the piston)

A little bit of sand paper to get off the gunk and it works great now, never jams or short cycles.

+1!

[gasol1ne]

hate to seem like a retard but can you please post pics?

[mr_benster]

hate to seem like a retard but can you please post pics?

+1 Please.

[beretta929mm]

Thise deserves to be a sticky.
Pleae post some pictures on the piston disassembly.

[Blademan21]

[QUOTE=gunsarefun;10274158]I started having issues with my 930 not wanting to cycle cheap bird shot. Never had a problem before and with about 250 rounds down the barrel, I figured it was time for me to clean it for the first time.


Are you saying that you put "about 250 rounds down the barrel" of a new 930 before you broke it down for a good cleaning? Shouldn't one clean a new auto/pump shotgun or any firearm before shooting it? Or is that FUD? Just asking for a claification on this.

[gunsarefun]

[QUOTE=Blademan21;10286090]

I started having issues with my 930 not wanting to cycle cheap bird shot. Never had a problem before and with about 250 rounds down the barrel, I figured it was time for me to clean it for the first time.


Are you saying that you put "about 250 rounds down the barrel" of a new 930 before you broke it down for a good cleaning? Shouldn't one clean a new auto/pump shotgun or any firearm before shooting it? Or is that FUD? Just asking for a claification on this.

I bought it brand new, oiled the action whenever I shot it, and put 250 rounds or so before I chose to clean it, since I was having some malfunctions. I don't normally completely strip down and "clean" a brand new gun. It's brand new, never been shot. If it's never been shot, then I don't see what there would be to clean. Everyone has their own system though.

I will go ahead and try to get some pictures.