I own the following Gen 3 Glock models - 23, 24, 31. I have purchased 9mm conversion barrels for each of them. I have the appropriate 9mm magazines for each. Do I also need to get 9mm model recoil springs for each of them in order to cycle 115 grain WWB or 124 grain NATO loads? Thanks in advance for your experience and recommendations!

Although this forum does know everything about everything, the brand specific forum might offer an informed response. brandtalk.com is that forum.

I would get the recoil assembly for each 9mm variant that you are converting to.

Some of the newer versions offer a captured spring that makes it easy to swap back and forth if you are likely to do so repeatedly.

If you are swapping to a complete unknown (like converting a Glock 21 to .38 Super), get a variety pack of springs.

Start with the heaviest weight spring and go to the next lightest spring weight until it cycles properly.

If you use a lighter spring than that it may still work, but the slide might be hitting the frame and damaging the integrity of both.

Let us know how it turns out.

Going from .40 to 9mm doesn't require swapping RSAs IME. In fact at least up to Gen 3 they were the same part IIRC.

I recently (about a year) got a 9mm "match" conversion barrel for my Glock 32 (same as a Glock 23 but in 357SIG), and I had also replaced my recoil spring as it was getting used up just about.

In any case after about 500 rounds of 9mm with the conversion barrel and no hiccups at all, have changed out barrels and fired .40/.357 and no problems either.

I think you'll be ok.

In Glock 40 to 9mm conversions I don't know that it matters that much- unless you want to save brass. If I recall correctly when I had a G22, the G17 recoil spring assembly was the same.

Or maybe I am confusing it with the factory spring assembly for the G30 and G29.



I have a few conversion semi-autos and change the recoil spring assemblies in all of them when changing caliber.

45 to 10mm conversion gets a change, 10mm to .40S&W gets a change, .38Super to 9mm gets a change, .40S&W to 9mm BHP gets a change. 7.62x25mm to 9mm gets a change.

However, I like my brass dropping around 10 feet from me.


For example, with my Sig P220 .38Super I was throwing brass about 25-30 feet away with the factory recoil spring weight.

I changed it until it dropped around 8-10 feet away.

However, then 9mm would drop 2-3 feet away or jam.

SO- I put a lighter recoil spring in for the 9mm and the heavier one in for the .38Super.


For reliability I could have used the factory weight and both calibers would have cycled just fine- but the shells would be dropping 15-30 feet away, depending on caliber fired.