Jump to content
Brian Enos's Forums... Maku mozo!

SP-01 Recoil Spring Weight

Recommended Posts

I realize there is a specific area for posting spring questions but it didn't have what I was looking for and I didn't know if you all checked that section or not.

I have been running 13 pound recoil springs in my SP-01 Shadows for the last 8 years or so and just now noticed they are making springs as light as 10 pounds. I shoot Production division and am shooting 147gr 130pf ammo. I don't want to beat the pistols up but obviously want them to shoot soft.

What spring weights are you all using?

Link to post
Share on other sites

emjei: That is a great point about hammer springs, that thought hadn't occured to me yet.

I have a factory hammer spring in my practice pistol since I run a Kadet unit on it, and a reduced power hammer spring in my match pistol.

Link to post
Share on other sites

I am not, by any means, and expert, but I have always read that the recoil spring should be matched to the ammo you run. The rule of thumb that I have read is that once I have a regular ammo, either purchased or reloaded, you want a recoil spring that allows you brass to eject approximately 8 - 10 feel from the gun. I shoot a shadow with 128-130 PF loads, 135 grain bullets, and use an 11lb recoil spring. Gun runs great and brass ejects 9/10 feet away, consistently.

Link to post
Share on other sites

In all my semi auto handguns I run the heaviest recoil spring I can with the ammo I use and still get 100% reliablity.

For my SP-01 this means a 14lb recoil spring with a 13lb hammer with a 115gr load at 135 PF. For factory CZ mag springs I could see this causing malfunctions, but no problems for me with 10% mag springs or mecgar mag springs. CZ OEM mag springs are notoriously weak.

For my 40 TS this means a 16lb recoil spring with the factory hammer spring (20lbs ?) with a 165gr load at 175PF.

I probably have close to 40000 rounds or more in my CZ's and have yet to break a slide stop.

I tried the 11lb spring and couldnt tell a dimes worth of difference in the recoil impulse. Controlling recoil for me is more about my grip technique than anything else.

Link to post
Share on other sites

You really wanna run the lightest recoil spring you can and the gun still operate with in reason. I run a 11# recoil in my shadows but need to try lighter. I also run a 11 in my tac sports at major and minor PF. the gun will track flatter with less heavy push into the hand translating into muzzle rise.

Link to post
Share on other sites

I pick my spring based on how my gun tracks and returns to target. As long as the brass comes out, I don't care how far it goes.

bingo. who cares where the brass goes. it may be one indication but the way to find the correct one for the ammo is to try them and see how the muzzle returns to battery. typically with light minor PF loads you really want the lightest spring you can run whilst still controlling the slide enough rearward and coming forward hard enough to pick up a round and go into battery. too light and it develops cycling problems.

If you're in USPSA you can run CGW springs. buy a few (say 10, 11 and 12). try them out. if you're shooting light 147gn loads probably the 10 will be best.

for IPSC I run a CZ 11 recoil and a old 13lb mainspring that is now down to 9lb! :)

Link to post
Share on other sites

You really wanna run the lightest recoil spring you can and the gun still operate with in reason. I run a 11# recoil in my shadows but need to try lighter. I also run a 11 in my tac sports at major and minor PF. the gun will track flatter with less heavy push into the hand translating into muzzle rise.

3. What weight recoil spring should I use with a particular load?

This is a very common but hard question to answer in exact terms and in most cases an exact answer is not possible. There are many factors which influence the correct weight recoil spring to use. These factors include the particular ammunition brand and load, individual pistol characteristics, individual shooting styles and your individual, subjective feeling of how the gun shoots and should feel.

The factory spring weight is designed to operate the pistol with what would be considered average loads, plus or minus a little. It is not uncommon for manufacturers to specify what they consider a factory ammunition load.

In general terms, the heaviest recoil spring that will allow the pistol to function reliably is the best choice - tempered by the above factors. As a rule of thumb, if your spent casings are first hitting the ground in the 3 to 6 foot range, then the recoil spring is approximately correct. If you are ejecting beyond the 6-8 foot range, then a heavier recoil spring is generally required. If your casings are ejecting less than 3 feet, a lighter recoil spring may be needed to assure reliable functioning.

Taking these factors into consideration, it then comes down to how the gun feels and performs when shooting - in your judgment. However, using too light a recoil spring can result in damage to the pistol and possible injury to you.


Recoil Spring Selection

A common problem with any auto loader is recoil spring selection. Many take the advice given on the net', which is typically incorrect.

Recoil springs will not lessen recoil by themselves, Newton's Law applies here: for every action there is an equal and opposite reaction. So the energy from recoil has to be dissipated.

Recoil spring selection for the average shooter is based on the ejection distance of a fired case. 6-8 feet is ideal. This generates the optimum slide velocity for reliable functioning and will let your slide stop live a long time.

Each pound change in recoil spring weight affects the ejection distance 1.5 - 2.0 feet. ​​ ​​​​

Example: ejection distance is 4' with the stock 14# RS; to add 4 extra feet go to a 12# RS.​​


Edited by Philo_Beddoe
Link to post
Share on other sites

Ok--I guess i'm just weird. Tried the 11 lb. Koolaid---just didn't do it for me.

Have 2 SP01 Tacticals. All the bells and most of the whistles, probably came close to buying David at CGW

a ticket to Hawaii from parts sales. Running a 11.5 hammer spring in both.

Load is 147 Bayou, 3.4 N320, PF 132.

Took a box of springs and a GM buddy to the range and we started playing switch the spring and running

against the timer on the plate rack. 10 lbs to 16 lbs. We BOTH got the best tracking/fastest times with

15 lb recoil springs. Guns run 100%, good ejection, and the sights are RIGHT THERE when to gun comes

down out of what little recoil there is.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...