What’s the difference between variable and regular 1911 springs

[Nick_shoots_fast]

What’s the difference? 

[jcc7x7]

Variable is wound differently on the end of the spring.

Makes the gun open easier and close softer.

Idea being less muzzle bounce or less sight /dot bounce.

Thus quicker follow up shots.

FWIW I've used them for 10-12 years

[Guy Neill]

To add to that, the regular spring is linear in force versus deflection.  Thus, a 5lb spring will yield five pounds of force for one inch of deflection (compression) and then 10 pounds for 2 inches and 14 pounds for 3 inches.

'

A variable is non-linear, perhaps giving 2 pounds at 1 inch, 5 pounds at 2 inches and 10 pounds at three inches - or such.

 

 

[echotango]

From Wolff:

 

The difference is both physical and operational. With a conventional spring, all the coils are spaced equally apart, except for the closed ends. In a variable recoil spring the space varies between coils with less space between coils at one end and more space between coils at the other end.

The way the two springs store energy is also different. For example if a conventional recoil spring is compressed 1/2", it might store 1 pound of energy. For every additional 1/2" this spring is compressed it would then store 1 additional pound of energy. When a variable recoil spring is compressed 1/2", it might store 1/4 pound of energy. The next half inch of compression might store 1/2 pound, the next half inch might store 3/4 pound and so on. In other words, a conventional spring stores energy on a straight line and a variable spring stores energy on a curve. If both springs are rated at 16 pounds, they will both store 16 pounds when compressed to the same working length, but the way they get to 16 pounds is different.

[Hawk21]

34 minutes ago, echotango said:

From Wolff:

 

The difference is both physical and operational. With a conventional spring, all the coils are spaced equally apart, except for the closed ends. In a variable recoil spring the space varies between coils with less space between coils at one end and more space between coils at the other end.

The way the two springs store energy is also different. For example if a conventional recoil spring is compressed 1/2", it might store 1 pound of energy. For every additional 1/2" this spring is compressed it would then store 1 additional pound of energy. When a variable recoil spring is compressed 1/2", it might store 1/4 pound of energy. The next half inch of compression might store 1/2 pound, the next half inch might store 3/4 pound and so on. In other words, a conventional spring stores energy on a straight line and a variable spring stores energy on a curve. If both springs are rated at 16 pounds, they will both store 16 pounds when compressed to the same working length, but the way they get to 16 pounds is different.

Great info.....so clearly the felt recoil will be different, which do you prefer on your setups ?

[echotango]

There is more to it than just the recoil spring. FPS and main spring also come into play(and other things). 

I used to use a var spring on my open guns, but have since switched to ismi springs. 

[Sarge]

Bob at Brazos had a write up about them in FS a few years back. He explained it very well and seemed to recommend them for Open guns especially 

[hiker88]

I was wondering about the difference as well. I just bought 4 different weight regular springs from Dawson as that was the only kind they carried.

 

I'm going to try variable springs as well to see what feels better on my Limited gun.

[cperazza]

I have had good luck with both fixed and variable springs (Wolff). 

 

Atlas Nemesis: Factory RS 11F / MS 17

 

Tested several combos:

RS Fixed: 10, 11, 12

RS Variable: 11, 12, 13

MS: 17, 19

 

Combos that performed well:

11F/17, 11V/17, 12V/17, 12V/19

 

For now I settled with 12V/17, but want to do more testing.