View Full Version : Mossy 500 AT Problem

October 25, 2001, 09:15 AM
I have a 12-gauge Mossy 500 AT that's about 20 years old. It's had a pretty easy life - I haven't shot it a lot - not obviously worn out at all.

Yesterday I took it out and shot some slugs and tactical buckshot out of it, and the gun was acting like it was a semi-auto. With most shots, the action opened itself up and sometime ejected the shell.

It wasn't a strong cycling like you'd expect out of a semi-auto. It just opened up enough to eject, and sometimes partially eject the hull, which of course caused it to jam.

It's as though something was out of time, or maybe some lock-up component is worn out. I wondered if I was causing it - by gripping the foream and reacting to the recoil...yanking it back... but I shot it one-armed and it did the same thing.

Anybody have any ideas?


Dave McC
October 25, 2001, 11:09 AM
Sounds to me like it's just getting broke in.See the recent thread on 870 jams....

October 25, 2001, 12:31 PM
Dave McC...thanks for the reply.

If anything, mine is the opposite of the 870 thread ... mine is (I think) too loose. Something is disengaging when it shouldn't be.

October 25, 2001, 03:39 PM
13yr old Mossberg 500 here. My Mossy does the same thing with various magnum loads. I actually appreciate it, as it speeds my pumping effort, especially when pass shooting geese. Heck, Winchester brags about the 1300 doing this, using it as a sales pitch "the pump action that thinks it's a semi-auto".