I'm the guy with a separate posting about an Anschutz 54 Match Rifle that has some accuracy issues. I have just received & installed a new firing pin spring in it, and will report back on it after I test it in the next several days.

With the indoor rifle season quickly approaching, I'm faced with another .22 rifle issue:

I have a pretty accurate Mossberg 144US that will fire & properly eject about 12 rounds before a spent brass sticks in the chamber. I've changed right and left extractors; firing pin spring, polished the interior of the chamber; soaked and cleaned the bolt face and interior with solvent; changed ammunition brands(Eley Club, Wolf Match extra, Geco Rifle, RWS Target Rifle, CCI Std.; Winchester T22, etc.).

The guys that I shoot with have nicknamed the rifle "Muzzleberg" because I have to manually take a cleaning rod and push out the brass from the chamber.

Anyone have any ideas of what may be the problem?

As before, you guys are certainly a wealth of knowledge, and I appreciate you help- very much.

If no one here has any answers, there is a huge and very knowledgable group of Mossberg shooters over on rimfirecentral. There is a separate "Mossberg" forum there to post your question.

By "ejectors", I'm assuming you mean extractors???? Did you also replace the extractor springs and plungers?

Sounds like a extractor issue to me, they get rounded off with use

Thanks for the correction---extractors, not ejectors. I did not change the extractor springs and plunger.

Thanks guys!!

Springs may be weak buddy. Make sure the plungers are not gummed up too. Generally those won't need to be replaced unless they are galled up. Good luck with it. I had a similar problem with my Mossberg Chuckster 640KD a few years ago. New extractors and springs made it like a new rifle again..

I did replace the extractors and firing pin spring, but haven't found any parts or instructions for changing the extractor springs or plunger on a 144 US.

I'll keep looking.

I have a Mossberg 144LS and had the same problem many years ago. A couple of people told me that these rifles are a little picky about the ammo and that is what is causing the problem. I changed out the extractor anyway. It has been awhile since I have used this rifle a lot but as far as I remember I can't recall having any more problems.

Have you looked closely at the chamber? It's possible that the chamber is pitted or has a ring in it from shooting shorts in it. Try wrapping fine steel wool around a bore brush and giving the chamber a good cleaning.