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G20 Gen 4 RSA spring weight ?

Discussion in 'The 10 Ring' started by seed, Aug 22, 2012.

  1. seed


    Aug 3, 2004
    Does anyone happen to know the RSA spring weight rating for gen 4 G20's? And just for reference, what is the difference compared to the gen 3's (what is the official spring weight for them now)?
  2. I was curious too since I own a new Gen 4 20. I just talked with Jeff, a tech. at Glock HQ and he said it was 17lb. same as in the Gen 3s. He said it's just the dual springs in the RSA doing the work of one spring. I told him it just feels stiffer than the regular Gen 3 recoil springs.
    That decides it for me when I will be shooting real HOT loads in my new 10mm.
    I'll just slip in a Gen 4 RSA adapter in the front of the slide, so I can use regular gen 3 compatible ISMI 22lb.-24lb. recoil springs with a ss guide rod.
    Last edited: Aug 24, 2012

  3. seed


    Aug 3, 2004
    Thanks for replying. I was beginning to wonder if my posts were somehow invisible or on some sort of universal ignore list! But that's another story. What's interesting is the physics of having a double spring. Using pure physics, it doesn't really matter if you have one or two springs if the combined weight rating of the two matches that of the one. The advantage of having two springs comes with being able to have more strength in a length where one spring is not long enough to do the job, as can be the case with subcompacts.

    Some people would argue that in some RSA set-ups, having a two spring system would divide the spring strength into initial strength of one spring until the second one was engaged to add further resistance against rearward slide velocity and that this would somehow better decrease felt recoil when compared to one strong spring. I guess the logic is that when you shoot a gun, having a strong single spring can actually increase felt recoil as the slide is met with more resistance. Personally, I don't buy it, especially when you watch slow-motion videos of guns firing shich seem to bare out that the final moment of rearward slide movement, when the slide impacts the frame is when you feel the brunt of the recoil impulse. Having a stronger spring and or heavier slide will make that moment less violent, even if they make initial felt recoil seem stronger...if they do.

    One interesting note: my Gen 4 G23 with the recall replacement RSA just makes casings come out very softly...almost too softly. Yet, that gun is still quite snappy. Interesting, if nothing else.

    So I guess that since Glock did not increase RSA power, they either bought the two recoil spring assembly superiority story and or realized that others did or just thought it would attract more sales.
  4. I agree with you on all points. Even though my RSA on my Gen 4 20 feels stiffer than regular stock, on the hotter 10mm loads, I'm going to be using the 22lb. spring. I know the slide is supposed to be heavier than a G21, but I don't want to have this fine gun battered too much, just because I'd like to let it "stretch it's legs".