ASP 9mm recoil spring
 

Howdy, folks!

Does anyone know the correct poundage rating for the recoil spring for an ASP conversion of the S&W 39? The factory spring is 14#, but the ASP is a cut down conversion and needs a stiffer spring. The 669 and 3913 use #15 if I recall correctly (the Wolff site is done right now), but even these are around a 1/4" too long.

I'm looking at buying some extra strength 39 or 3913 springs and need to know what poundage to order. Has anyone dealt with this problem before?

Thanks,

All I can suggest is buying a selection of 3913 type recoil springs and shorten them to size, then test fire, starting out with the strongest poundage.

Reduce the spring one pound at a time until the gun is reliable and throws the fired cases a reasonable distance.
Too far and the spring is too light. Too close, not strong enough.
Too strong is better as long as the gun is reliable.

Thanks!
 

Thanks for the feedback. This is the strategy I plan on using. I was hoping someone else had already sorted this out. I guess not many folks intend on shooting their ASP anymore. I probably shouldn't either but I hate keeping something as just a safe queen.

This sort of thing is common with custom guns.
If anyone ever knew what weight spring was used it's been forgotten.
Since no one remembers, this leaves you to experiment.

One way you might be able to find out......
If you're an NRA member** you can send the American Rifleman Dope Bag a SASE with ONE question per letter and the Rifleman Tech Staff will answer it.
If anyone knows about the Asp they would know.

** Shame on you if you aren't.