I know the spring on the M9 is captured....but those of us who use the stainless steel rod from 12 Volt Man have removed it from the factory rod and reinstalled it on the new one. Does anybody know what the rated strength of the M9 spring is? 15 lbs? 16 lbs? I'm willing to experiment with some different springs to see if I can find a good substitute, but it would help to have a starting point. On a similar note, is the spring for the S9 captured or free? Thanks. Jim
The S9 also has a captured recoil spring. However, it is on a steel guide rod, rather than the plastic rod for the M.
I guess there are two purposes. First, some people like to "adjust" their recoil for different loads...using stronger or weaker springs depending on what kind of load they use. So that's one reason. My purpose is more practical -- the uncaptured recoild spring is more difficult to reinstall than the factory captured set up. It's about twice as long as the recoil rod, so it takes a little manipulation to get it back into place. If I could figure out an "equivalent" to the factory spring (strength), then maybe I could come up with a shorter version that provided the same recoil (and was easier to install). To be honest, I need to sit down and do some thinking about the relationship between the spring length, the spring coefficient and its relationship to the gun's operation. My Ruger has an 11-lb spring that's twice as long as the 16-lb spring in my Sig. Is that because the slide travels further? If anybody wants to chime in, I'm happy to hear about the proper operation of the recoil mechanism! Thanks, Jim
Wolff springs I e-mailed Wolff this week about springs for an M9...they responded that they have no info on the M9. So we will have to figure it out ourselves i guess. Greg
Navy, The longer, softer, spring provides a more constant level of resistance throughout the working range of the mechanism. Spring selection for a Steyr will be quite a bit different than selecting one for most conventional autoloaders. In conventional designs the hammer helps hold the slide in battery during firing and the work of cocking the firing mechanism is fully accomplished during the back stroke of the slide. In the Steyr the recoil spring has to provide all of the force to hold the slide and barrel in battery AND the recoil spring also has to do the work of pre-loading the firing mechanism. Both of these factors place a premium on having a recoil spring which generates a fairly high level of force when the slide is in battery. Bottom line: A shorter, stiffer, spring is more likely to produce out-of-battery problems and/or excessive force near the rear of slide travel (short stroking). There may be profit in tinkering with the spring rate a bit but I would be skeptical about shortening the spring by a great amount. I have no experience with Glocks, but, because of the similarities in function, that's the first direction I'd look for alternative recoil springs. The possible dimensional differences may dictate the use of different guide rods with them or may rule them out altogether, though.
