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P320FS / M17 recoil spring

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February 16, 2019, 10:27 AM
MNSIG
P320FS / M17 recoil spring
My new M17B is a great shooter, but extraction is very weak with practice ammo. With either Speer Lawman(124) or Federal American Eagle(124), the empties basically fall on my arms. I've had a few stovepipes in the first 200 rounds and the slide never locks back on empty.

I'm guessing the recoil spring is set up for full power military or duty ammo. Extraction seems fine with Speer Gold Dot +P 124gr and the slide locks fine. The practice ammo just isn't getting the slide back far enough to engage.

Is this something I can expect to improve with break in, or is a lighter recoil spring needed for range ammo?

Thanks
February 16, 2019, 10:39 AM
Oat_Action_Man
I don't know if the recoil spring in the V-tac is the same, but I had similar experience when mine was new.

I had a handful of failures to eject with light loaded practice ammo; ejection was barely dribbling out the side of the gun otherwise. No such problems with 124 gr loads or +P.

I've got more rounds through it now and I have noticed a considerable improvement in the ejection with light loads, and have no failures. Gun is 100% at this point.

I never experienced anything like this with my compact, so it may be the full size spring.


----------------------------

Chuck Norris put the laughter in "manslaughter"

Educating the youth of America, one declension at a time.
February 18, 2019, 06:37 AM
Fredward
Milspec NATO ammo is about as cheap as what you’re using. Rather than change springs I’d change ammo.
February 18, 2019, 06:49 AM
sigfreund
Grayguns offers a recoil spring guide (rod) for the full size P320 that is used with 1911 recoil springs. The springs are available in different weights so that’s an easy method of adjusting for the power of various ammunition types.


https://grayguns.com/product/c...ess-steel-guide-rod/




6.4/93.6

“Wise men talk because they have something to say; fools, because they have to say something.”
— Plato
February 18, 2019, 07:01 AM
MNSIG
I need to shoot non-toxic at my primary range, so mil-spec is not going to work.


I ordered the Grayguns rod/spring. Thanks!
February 18, 2019, 11:40 AM
sigfreund
Hopefully the 15-lb recoil spring supplied with the Grayguns guide will work with your lighter loads. I have one in my 9mm P320 and with somewhat wimpy 115 grain Blazer aluminum, ejection isn’t vigorous, but I have had no malfunctions.

One thing I sometimes experience with the GG rod is that the slide doesn’t want to move forward after turning the takedown lever down. If I lift up on the front of the rod that releases it.




6.4/93.6

“Wise men talk because they have something to say; fools, because they have to say something.”
— Plato