Help with main spring retaining collar

[h46pedro 0]

I finally had time to shoot my Johnson and the main spring retaining collar kept coming unscrewed.

While shooting a 20 round clip on full auto it backed out two turns.

Any information on why this is happening and how to fix the problem would be greatly appreciated.

Thanks,

Al

[Brian Alpert 0]

You are apparently missing the "Main Spring Tube Screw Retainer Spring" which goes around the tube screw (under the collar), hooks thru a slot in the collar and engages one of the slots on the rear of the tube screw preventing it from rotating. You have to pull out the hook from the slot to turn the tube screw when this spring is installed. Numrich has them for under $5.

[h46pedro 0]

Thanks for the information.

I ordered the spring plus a few other part.

Thanks again,

Al