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Mossberg SA-20 Troubleshooting

ATTN JOHN -
Do you have a picatinny rail install on your SA-20? If so.. that is your problem right there. It's the front screw that hold the rail on the barrel. It's seating too far down through the chamber and hitting the barrel, thus putting downward pressure on the barrel and preventing you from removing it. Ask me how I know :) I spend hours trying to figure out why I couldn't get my barrel off. Just loosen that front screw up a little bit and the barrel will fall off...
Yes it does, thanks I'll take a look at it this weekend.
 
First time poster. Thanks for all the information on the SA-20 you regulars have posted.

I have a brand new SA-20 Tactical. Was happy to see the Mag Follower (11) was RED. Simplifies "chamber check, mag check". If you see red, no shell in mag. Removed the Mag Plug (14) for a "1 in chamber, 5 in mag" capacity. Ordered the 2 shell mag extender. Read all the problems with various ammo.

This morning I shot the following sequence:

Winchester Super X, High Brass, 2-¾", ¾ oz. 1600 fps slugs. Shot 60 rounds (10 6-shot loads) and the SA-20 cycled flawlessly!

Remington Slugger, 2-¾", 2-¾ Dr Eq., ⅝ oz. hollow point rifled slugs SP20RS15. 60 rounds (10 6-shot loads) of flawless cycling!

Winchester AA, Super Sport Sporting Clays, 2-¾", 1300 vel., ⅞ oz. 7-½ birdshot, low brass. 72 rounds (12 6-shot loads) and the jams started! Almost every first shot did not eject and half the time the second shot would not eject. The following 4-3 shells in the mag would cycle successfully.

Winchester Super X, High Brass, 2-¾", 1220 vel, 1 oz. 6 birdshot. 60 rounds (10 6-shot loads) and SA-20 experienced only 3 ejection failures.

As expected the two different brands of high brass, high muzzle speed slugs cycled flawlessly.
The high brass birdshot had a couple failures.
The low brass birdshot had many failures.

I'll do a complete cleaning and polish the chamber (stiff brass bristle brush w/fine steel wool and maybe polish some of the bolt assembly slide areas as described in this forum and see if anything improves.

Thank you! Thank you!
 
Welcome to the forum from NY and congrats on your new Mossy. You get a chance post a pic or two.:)
 
Just bought a new SA-20 for my wife and daughter. First time out we have had some trigger issues. After you fire the first round and try and take a follow up shot it will not fire. Pull trigger again and it will. Need to pull trigger twice on second shot. It dose not happen every time. I took trigger assembly out and have found that the rear spring is so weak it dose not apply enough force to push toggle arm back down. Toggle arm is not the correct name I'm sure but can not find a parts list for the trigger assembly. It is at the very rear of the asssembly. Anyone else having this issue?

Well I stoped by the gunsmith today. I had left the SA-20 there on Wed. They were able to duplicate the problem. I was told it is not the spring. It is made that lite for a reason. The toggle is rubbing on another part. The gunsmith said he will polish the parts and it should solve the problem. Hope to get it back on Sat. I'm just very happy that it does not need to be shipped back to Mossberg!!! Will keep you all updated--
 
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I purchased an SA-20 in February but was unable to shoot it until Saturday (5-9-15) when I attended the NRA Basic Shotgun course. It was a ten hour course and well worth the time & money.

However, when the instructor and I took my SA-20 to the range, the trouble started (yes, it was one-on-one as I was the only student). I was told to purchase target loads for my shotgun so I bought Federal Target loads 20 gauge shells; 2 1/2 dram weight; 7/8 oz; #8 shot. The instructor loaded the gun and attempted to fire it. It would not recycle the shells and they also became jammed. He tried several shells but basically, they would not work. Then we tried some Federal Premium Defense 20 gauge shells; 24 pellets - #4 buck shot; 1100 FPS - copper plated. These rounds worked flawlessly. The instructor then went back to the lodge and brought back some Remington rounds that he thought might be heavier (close to 1 oz.) and we got mixed results. The instructor told me this probably shouldn't happen but did note the shotgun was sold as a "tactical" shotgun and he thought it should use a heavier (1 oz) rounds.

I called the Mossberg phone number listed in my Owners Manual and he stated that since the shotgun is made in Turkey that the shell sizes are not exactly the same in the two countries. He said if I looked in the Owners Manual that I should use 3" magnum shells between 2 3/4" (15/16 oz) and 3" (1-1/4 oz). I think this was the problem with my gun but will not be able to try it again for awhile since I have to shoot it at a range far away from my home.

Besides the Federal Premium Defense 20 gauge shells, what other self defense or field loads have others had luck with in the SA-20 so that it cycles and loads correctly? I am going to return to Bass Pro Shop after I get some advice from other members and purchase different shells.
 
Just bought a new SA-20 for my wife and daughter. First time out we have had some trigger issues. After you fire the first round and try and take a follow up shot it will not fire. Pull trigger again and it will. Need to pull trigger twice on second shot. It dose not happen every time. I took trigger assembly out and have found that the rear spring is so weak it dose not apply enough force to push toggle arm back down. Toggle arm is not the correct name I'm sure but can not find a parts list for the trigger assembly. It is at the very rear of the asssembly. Anyone else having this issue?

Well I stoped by the gunsmith today. I had left the SA-20 there on Wed. They were able to duplicate the problem. I was told it is not the spring. It is made that lite for a reason. The toggle is rubbing on another part. The gunsmith said he will polish the parts and it should solve the problem. Hope to get it back on Sat. I'm just very happy that it does not need to be shipped back to Mossberg!!! Will keep you all updated--
Well, what happened?
 
I use the AA 1200/1300 fps 7/8 oz 7.5 and 8 with no problems. I do have quite a few rounds through it though. Probably 2k or so.
In the beginning I had to use 1oz high brass. It seems to have "loosened up a bit" now.
Keep it a little "wet" lubed for a while.
 
Even I , an amateur, a novice -know that unless your Thug is "worked" ,or thoroughly broke in - it will not readily cycle sissy ammo .
 
I found mine loves the 3" shells but has problems with 2 3/4 stuff unless it's a beefed up load. I am sure with time it will get better - but for now it "stove pipes" the "sissy" ammo ;)
 
Hello All,
Just bought a new SA-20. I disassembled, cleaned and reassembled this morning. I loaded for the first time, then unloaded. Unloading the magazine tube did not go well. I pushed the elevator up and depressed the shell stop. The shell was released, but ran into elevator and stopped after about 1/2" of travel. After inserting and releasing multiple time, I got it come free of the gun. Another time I released the elevator and the shell ejected from the tube into area above the elevator, between the bolt and chamber. Luckily there was no shell in the chamber, or dis-assembly would have been required. I finally just cycled the remaining shells into the chamber and ejected by use of the bolt operating handle. This was with Remington Express "high brass"shells.

I decided to try different shells and tried Winchester Super X "low brass" shells. the metal is silver so I guess not brass. Anyway, the shells were released from the magazine tube better, but not consistently.

Is this just a trait of a new gun, or should I take it to the dealer for some rework or polishing?

Thanks!
 
I don't own a SA20 ,,,,,,but I would take it out and shoot it and see how it does.
 
Okay Jim, welcome to the forum. Old Mossy is right, shoot the gun normally and make sure it works correctly under all conditions and ammo. They can take some time to break in. And keep it clean and lubed.
Secondly, order some dummy rounds if you are going to cycle the gun when not intending to fire. I found them on line, not snap caps, actual loaded shells with shot, but no powder and no primers. Works great and much safer.
Thirdly? There is a small issue with some guns. There is a tab on one side of the lifter that hits the action bar when the lifter is depressed and causes the lifter not to go all the way up, making it difficult to unload the magazine. In some cases, this can also make it hard to load when extremely high. It doesn't sound like you have that loading issue. Some of the guns even had some factory grinding done on the tab I assume to make it clear better. Did you notice any of that on yours?
The problem is that the tab cannot be ground off because it is involved in the gun timing. Leave it as is for a while and see if it gets better. If not, a while back, I had posted some pics of a modification I did but it involved grinding in tricky areas. Not recommended unless the gun does not run correctly and then only through as gun smith.
Great gun, very light and fast and the light recoil lets me shoot all day with no pain. I love shooting it and I have used it in many competitions (tactical and 3 gun, no trap or skeet matches) I have the 20 inch tactical barrel. The only real problem is the teasing I get for using a "kid's gun" (20 ga) at the matches.
Enjoy it and let us know how it goes.
 
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