Is there a downside?

[LocoGringo]

Hello guys and gals. I hope this is the correct forum. I've just finalized the load for my STI Marauder and it's a stout load. I'm sending a 9mm 135 grain coated lead bullet around 1075 FPS. I've "tuned" the pistol and gone from a 10 pound factory recoil spring to the Wolff 15 pound recoil spring. It has not had any problems ejecting (yet). I'm surprised the spring power increased by 50% and has been reliable so far. I'll keep the other, lighter weight springs with me until I've gone through a solid 200-300 reliable rounds, but my question is this. I got the higher strength springs to keep from beating up my pistol, but is there a downside to a heavier recoil spring? If it proves reliable, does the higher strength spring negatively affect accuracy or function or anything else?

I chose the stout load because I want to knock down steel targets with authority even if I happen to hit the steel a bit low or send over a spinner without having to hit it a lot as long as I'm accurate. I understand the pistol will have more recoil, but I want to get used to controlling recoil better as a general shooter and not "game" true techniques. This is my first foray into tuning a pistol to match a load.

 

[CZ9shooter]

The slide will now slam forward with more energy. Is this a bad thing? I dont know.

To me it doesnt seem to make a difference. Either you run a lighter spring and the slide comes back faster, or a heavier spring and it returns home harder.

More energy generated by your ammo will REQUIRE more energy to be dissipated somewhere. More energy equals more wear and tear. No way around it.

However, I dont feel that your load is too overzealous. Your gun will probably be fine.

 

[BBBBill]

You might try a square bottom firing pin stop in conjunction with a lighter recoil spring. The square bottom stop reduces the leverage of the slide against the hammer due to its lower contact point on the hammer. The square bottom should have at least a tiny radius put on the bottom corner and can be tuned incrementally by slowly increasing the radius until desired function is achieved. The recoil spring should be chosen to provide correct function (getting the brass out and away from the gun/feeding the next cartridge into the chamber) and give the best recovery/sight tracking for the shooter. The square bottom stop will allow a lighter spring which will minimize the hammering on the slide stop pin as the slide returns to battery and reduce muzzle dip induced by a heavier spring.

 

[JRadice45]

You might be better served with a 12 lb recoil spring and the square bottom firing pon stop as bill suggested. If the pistol does not have one installed an 18.5 lb mainspring would not be a bad idea also.

If you are that worried about smacking the steel with authority you could try loading 147gr bullets, or stick with standard 124 gr bullets and work on your accuracy so you dont have to worry about not hitting a plate in its sweet spot with 9mm.