What sort of RSA for G40 would be best for a heavier spring?

[Roguer]

I'm looking to get a stronger recoil spring for my G40, 22 to 24 lb spring. Since I'll have to use a gen 3 style rod guide I found a few guide rods. Some have precaptured springs and have a RSA adaptor for the Gen 3 RSA. One I found is a gen 4 rod guide where you just put the spring on.

So I was wondering would it be ok to use the RSA adaptor for a gen 3 rod to fit the gen 4, or get the gen 4 guide rod and add the spring for a captive spring.

Another question is a captive spring needed?

I'm leaning to the glock store captive 22 lb spring and adapter for gen 4 glocks. https://www.glockstore.com/Tungsten-Competition-Recoil-Spring_3?quantity=1&custcol7=52&custcol9=13

Or a "roll your own" type with the gen 4 I've seen. (I think it just might have an adpter thrown in. https://www.glockmeister.com/Gen4/products/465/

I figure the more experted people here might know a thing or two about this. 

[The_Shadow]

Well I have been using the non captive recoil rod from Wolff gun Springs and use there 22lbs spring in my 3rd gen 20SF.
The newer G-40's have a longer slide with possibly a little more mass than the shorter G-20's, but 20 to 22 lbs should do well to help slide speeds...

[Spudmeister]

My Gen 3 G20 with a 20 lb spring (+ 5.3" Storm Lake barrel) has a great deal more slide velocity than my G40 with the OEM spring.  My example is with 180 and 200gr bullets from moderate to hot loads.  I also note the G40 does not throw the brass near as far.  IMO Glock got it just right with the OEM G40 spring.  All the more so with the KKM 6" bbl.

I think the OEM G20 does a better job with the full range of 10mm ammo (or reloads) as the G40 is very sluggish with lighter loads. Opinions vary but this has been my experience.

[sep]

My Gen 3 G20 with a 20 lb spring (+ 5.3" Storm Lake barrel) has a great deal more slide velocity than my G40 with the OEM spring.  My example is with 180 and 200gr bullets from moderate to hot loads.  I also note the G40 does not throw the brass near as far.  IMO Glock got it just right with the OEM G40 spring.  All the more so with the KKM 6" bbl.

+1 My G40 doesn't toss empties as far as my STI Perfect 10 nor my Dan Wesson Bruin. I like the dual spring setup of the G40. I'm running a Glockstore Stainless RSA but it's not designed to remove and replace the springs. Lonewolf makes a stainless version where you can replace the springs but I did not see extra springs for sale on Lonewolf's web site. (just made a cursory look) So, I'm probably just gonna go back to the stock RSA at my next spring change.