9 replies to this topic

[DINK]

Tired old memory is at it again. Would one of you gentlemen please remind me what the correct length would be for a 1928 recoil spring?

Thanks

[JimFromFL]

If i remember correctly, 10.5 inches.

[PK.]

According to TM 9-1215, the acceptable length for the recoil spring during inspection is 10” +.25 “. Most new springs of GI or good commercial manufacture are coming in as long as 11.75”. Keep in mind that a new spring will “set” in it’s first period of use.

In my experience, a good used spring will be 10.75” – 11.25” free length.

Please keep in mind that there should be 67-70 active coils in the spring, I have seen them where guys have cut them off and then stretched them out again- not good.

[john]

The one I'm currently using was a GI surplus....bought a half-dozen from LMO/Dan Shea a few years back. These are long....over 12 inches.
With advice from the pros (can't remember who) here on these boards I cut it down to 11 inches and now that it's broken in (at least a couple thousand rounds) it measures just a tad over 10.75". Also, I also have an extra urethane buffer installed so that would "add" to the length about 3/32".

And it functions flawlessly.

john

[Dave Janowski]

From the military print A5153024 free length is 11 5/16 +/- 5/16. The print also calls out specific loads at specific heights along with total number of coils and left hand helix. If you want my opinion this is why we should NOT cut springs to make them weaker, or stretch them to make them stronger by doing this he "rate" or "constant" will change, hence changing the specified loads

Dave

[Merry Ploughboy]

From what I’m reading, it seems like length is not too important, within limits, so long as it’s stiff enough to do the job properly.

For instance, sounds like if a little has been cut off the end (say for religious reasons) it should still be able to do the job of one that’s unaltered.

Also sounds like as it gets older, it may not be as stiff as it used to be. In that case, maybe some special lube in the receiver could help.

When it’s working in a receiver that’s worn and sloppy, it may have to be extra stiff to get the action to work right. Likewise, when working in a new, tight receiver with hot ammo, it should be extra stiff.

There also seems to be an active market for those who want to improve the stiffness.


(Chris/Nick, Zap this if you want. Satan made me do it.) MP

[21 smoker]

MP... you had me until....`For instance, sounds like if a little has been cut off the end (say for religious reasons)`.......

[DINK]

I thought this was going to be a very routine thread, but I guess I forgot what a demented bunch of posters we have here. Thank you all for the info, both expected and unexpected!

[wpuckett59602]

I installed a new recoil spring in my 1928 West Hurley Thompson. It was 11.0 inches new, but now measures 10.5 inches.  I was told that a new spring should be around 11 and 5/16 inches. I am getting some jams where the shell is pushed slightly forward in the magazine. These occur in both 20 and 30 round stick magazines. The actuator sticks about half way back.  I have to eject the magazine and push the shell back.  For some reason this doesn't occur when I fire the gun in "semi-auto" mode.  I thought perhaps a new Wolff recoil spring might solve the problem?

 

I don't get the jams when using a 50 round magazine, but sometimes the gun misses a round. The actuator will be stuck forward when there are still shells in the drum. I have to pull the actuator back to complete firing.

[klocker]

I just changed out my m1928A1 spring. It had frequent misfires, in like chambering the round with a light impact on the primer. Not deep enough to fire it off.    Turned out the spring length was a little under 9.5 inch.  The new one I put in measures little over 11 inch and shoots like a charm now.