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Correct Length Of 1928 Recoil Spring?


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#1 DINK

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Posted 15 November 2004 - 08:04 AM

huh.gif 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
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#2 JimFromFL

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Posted 15 November 2004 - 08:23 AM

If i remember correctly, 10.5 inches.
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#3 PK.

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Posted 15 November 2004 - 09:09 AM

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.

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#4 john

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Posted 15 November 2004 - 03:26 PM

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. tongue.gif

john
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#5 Dave Janowski

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Posted 23 November 2004 - 08:26 PM

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

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#6 Merry Ploughboy

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Posted 24 November 2004 - 02:06 PM

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
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#7 21 smoker

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Posted 24 November 2004 - 06:08 PM

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

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Posted 26 November 2004 - 08:06 AM

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! laugh.gif laugh.gif laugh.gif
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