Springing the 1911...

I suspect that for each level of recoil, there is an optimum recoil spring. This aids in maintaining lockup and hence accuracy while allowing the gun to function. Light springs may be poor shooters while too heavy won't cycle.

As a guide I am seeing a nice fit with a 10# and 3.5 BE with 200s. It helps with follow through.

I realize that friction from lockup comes into play buy suspect it's less of an issue.

For 200s:

3.7 needs...

3.9 needs...



Thoughts?

Much seems to depend on the individual pistol. With 3.5 BE I’ve had one that functioned perfectly with a 13# spring and another that needed a 10 #. I use a 20# mainspring in my wadguns and go as heavy on the recoil spring as function will allow. I’m using a 13# flat wire spring with a full length guide rod on my current wad gun. This is a very tight pistol but still functions perfectly with 3.5 BE/200swc.

I find a 13 lb works quite well. 

I went to flat wire and the 12 was way too short and wimpy.
I went to 15 lb flat wire in my wad gun. I have an SRO slide mounted dot and it locks up really tight.  4.0 WST or 4.0 Bullseye and a 200 SWC.  It operates with most anything.

I went to a 17 flat wire for my general purpose 45.  It will shoot 4.0 WST or 4.0 Bullseye  with a 200 SWC.

If you go to Wilson Combat there is a short note to find the heaviest spring it will function with and go one lighter.   They have kits of different weight springs.

David

You might also need to look at the mainspring and the radius of the firing pin stop. The main job of the recoil spring is to put the gun into battery. If it short strokes with, say, a 12# spring, and doesn't go into battery 100% with a 10#, you might get it to work with the  12# and a lower mainspring.

When you reduce your recoil spring you're going to want to install a buffer on your guide rod! You won't be sorry.

As it was said, recoil spring brings the gun fster into battery, but it also slows slide recoil impulse. The more delay in the recoil impulse the less perceived recoil. However, the gun is the sum of its parts. The more squared the radius of firing pin stop the quicker it stops the slide, but the worse is the racking of the slide. The more robust the mainspring the faster it has the hammer stopping the slide, but the harder it is to cock the hammer. The more robust the recoild spring the faster it stops the slide, but the more forward slap of the slide and the more force of getting bullet out of magazine and into the chamber = more possibiity of malfunctions. Everything has to be set up to work in harmony and unfortunately no 2 guns are the same just due to geometries of all parts. There are some winning combinations though. Personally I like easy racking of slide and hammer as the less force you use between the shots the more relaxed your hands are for shooting. So I round off firing pin stop as much as I can, use 16-19lb mainspring for a beautiful hammer and trigger action, then 13lb recoil spring to compensate the tension I took off the rear end. This way the gun feels smooth all around. Other way to do this is to put a more square firing pin stop, like a 20-23lb main spring and a 8-10lb recoil spring. So more tense on the back end but easier on the front end. This will work better on wadcutter rounds to slide them into the chamber with less force nice and easy. I hope I am making it undestandable.