[aa214]

I just ordered a Glock model 31 chambered in 357 sig and I plan on using hot underwood ammo rated at 1500 fps and I was wondering do I need a after market recoil spring and rod or should I just use the original it comes with? From what I have read the recoil spring in the 357 sig models is the same one they use in 9mm and .40 and I dont want to beat up my new glock. thanks for helping

 

[Pancho_Villa]

I would assume they would put the appropriate rcoil spring for the caliber. But I am new on Glocks, so I am guessing.

I have an old G17 I got last year and a G23 I got 2 years ago. I had planned to get a spare barrel for the G23 in .357 Sig. Again I am assuming they will send the right spring for the caliber to convert. However, a local guy has a 31 he kinda wants to swap off. So, I may come up with something on that gun. He never shoots it and he got it from his nephew that was a state trooper. That guy didn't like the recdoil according to the uncle.

 

[darkwriter77]

Most caliber conversion barrels I've seen (and ordered) do NOT come with a recoil spring. You have to order that separately. If you do add an aftermarket recoil spring, I wouldn't get one that's TOO stiff because it can cause the action to short-stroke (kick out the empty but fail to strip another round off the mag) or cause stovepipe jams if the ammo you're shooting isn't potent enough.

From the Wolff springs website:

For use in:
Glock 17, 17L and 34, 9mm
Glock 20, 10mm
Glock 21, .45 ACP
Glock 22, 24 and 35, .40 S&W
Glock 31, .357 Sig
Please see ratings note below.

* Reduced Power...: 10, 11, 12, 14, 15 and 16 Lb.
* Factory Standard.: 17 Lb.
* Extra Power.........: 19, 20, 22 and 24 Lb.

Above recoil springs.....Stock No. 437xx....$ 7.89 eaClick button to purchase
Please Note: Replace the "xx" in the stock number with the pound rating of spring.

Recoil Springs
For use in:
Glock 19, 9mm
Glock 23, .40 S&W
Glock 32, .357 Sig
Please see ratings note below.

* Reduced Power...: 15 and 17 Lb.
* Factory Standard.: 18 Lb.
* Extra Power.........: 19, 20, 22 and 24 Lb.

 

[aa214]

I was considering trying a 19 lb spring do you think that would be the right one for shooting hot 357 sig ammo?

 

[darkwriter77]

It's two steps above the factory spring. I don't think it would HURT anything, really, but again you'd have to make sure it was some significantly more potent ammo than the standard factory stuff.

The problem with .357 Sig and .40 S&W in Glocks isn't anything to do with the recoil spring, but rather the fact that Glock took a platform/frame that was originally designed around 9mm and then later decided to start putting higher-pressure/more potent rounds through it, hence the reason .357/.40 Glocks don't last as long. Their frames just don't hold up well over time with those rounds. The Glock 20, however, was designed for 10mm right from the start, hence the larger dimensions, and it can shoot all kinds of spicy stuff. Similarly, the G21 of the same frame handles any degree of .45 ACP without issue.

Putting in a stronger recoil spring may or may not help give it a bit more longevity, or at the very least might somewhat reduce felt recoil, but bear in mind that any .357 or .40 Glock is not going to have as long a service life as a platform such as, say, an M&P or P320 that was designed from the very start to handle those cartridges.