P-64 Springs -The strongest recoil reduction available?

[robhic]

Glad to see forum rules don't apply here. Thanks for the thread hijack. Close thread. Thanks anyway.

You started the discussion regarding the 'best' spring combination. Well, we were discussing springs and different problems that may/may not occur when using them. I don't know that there IS a "best" spring combination because different people have experienced different things with different springs. Some said the 17# trigger spring could cause mags to drop. In MY pistols, it hasn't caused the slightest problem. Curly said the 22# recoil spring caused mag-drop in HIS pistol (he thought). Made me curious because I am intending to try a 22# spring to address another issue I'm having. So no combination is "best" because they seem to be subjective. You're certainly sensitive .... We're talking sprigs. Read and digest the information presented.

[Curly1]

+1 ^^^^^^^^

[Ketchman]

srREXed and others,

The problem with the recoil issue begins with the weight and size of the weapon and the type of round being fired and ends with the term "percieved" or "felt". Recoil forces are the same with the 9x18 round no matter what firearm it is fired from as physics is physics. The difference lays in the mass of the firearm and the size / shape of it. If you fire the 9x18 in a CZ 82 you will find it is delightful, but you will find that is because the CZ 82 weighs more, is larger and the grip being double stack distributes the recoil forces into the palm of your hand over a larger area and therefore "feels" lighter. Fire the 9x18 in an FEG PA-63 and the recoil will feel sharper as the grip is narrower AND the weapon weighs much less (Aluminum alloy frame vs all steel), therefore there is less mass for the recoil forces to overcome before pushing into your palm. When firing the P-64 you must take into account the frame is the most narrow of the 3, the grips come together and form a seam right down the middle where it is pushed hardest into your palm and the gun is the smallest, if not the lightest, and therefore MUST concentrate all the recoil force into the smallest area of your hand. And if you think having that seam there does not make a difference fire one with one edge a bit taller than the other, you will come 'round right quick. And these differences between these 3 different guns occur firing the exact same ammunition which has the same grain round and velocity, which means the amount of forward and rearward force upon firing, remember Newton here folks, is the same. So..., that being said changing recoil springs WILL make a difference in how much recoil makes it to your hand but the difference is very small, 4 pounds between the 16 and 20 pound springs from a round that says to develops 210 ft /lbs +/- of energy at the muzzle and therefore will be very difficult to detect the difference at best. I BELIEVE that when I swapped my stock recoil spring for a 20lb unit that the recoil did indeed feel lighter, but was it actually really lighter or in my head because I knew it SHOULD be lighter.
In all reality, you are all right in a manner so stop shouting names, the recoil will be a tad different when changing springs, some of us may be able to feel the difference but some will not due to our difference in individual nervous systems. And frankly, with a gun this size and weight firing a round of this power it is going to be snappy no matter what you do to it. Either you can live with it, love it or just plain hate it depends on your personal preferences. And Curly's experience should be proof, the mag is held in place by the hammer spring yet changing the recoil spring made his mag either drop or stay in place, proof that a higher pound recoil spring absorbs just enough more energy that the shock to the hammer spring through the frame was just enough lighter to leave the mag in place.
Sorry for soap boxing but I don't want to see another thread possibly get close to being out of hand. We are all too good a people for that kind of thing.
I will shut up now. Thank you all for your patience.

[robhic]

Very good and interesting. I HATE math and physics frightens me! I had a handle on the "mass" part making recoil a bit better due to gun weight. But that was enlightening. Any chance you are/were a teacher? I'm gonna try a 22# spring not to decrease recoil, felt or otherwise. I have a slide-lock lever that sorta "jumps the track" in one of my P-64s and it pinches the ridge/rim in the slide that it's supposed to hit so as to lock the slide back. Mine slips off and pinches this ridge (just inside the back of the slide) effectively jamming the slide on emptying the mag. I compared it against another 1975 pistol and it looked just a bit bent inward. So I bent it outward and figure that maybe a heavier (I'm using the stock weight 18# spring now) spring will give just a tad more resistance and cushion things so they don't slam together. I'm gonna try it with just the bent-in lever first, then, if that fails, I'm gonna swap the recoil springs.

[Ketchman]

Robhic,
No am not/ was not a teacher and do not wanna be 'cause I could not deal with the kids of today, they have no respect for others and even less manners, but thats a whole different soapbox. However anyone who WANTS to teach these days has my everlasting respect for guts, bravery and determination.
Thank you for the compliment. I just know that when my brain is trying to wrap itself around something it sometimes needs a COMPLETE description as to all the why's, how's and therefore's before the lightbulb upstairs starts a glowin, so I explain stuff that way when I think it might be a bit convoluted for others too. And I think your trying out the potential fix you have made without swapping out springs first is the smart way to go, one variable (known) at a time.

[Ketchman]

Robhic,
If your slide hold open lever repair does not work you may have a spring problem, but it would be the spring that pushes down on the lever, It may have been weakened and it is not providing enough downforce to the lever to keep it in's it's proper place during firing. I may be wrong but it's a thought. And seems like there was a brother on this forum who may have been making / selling them. Anyone out there know who that was?

[spareparts]

Robhic,
If your slide hold open lever repair does not work you may have a spring problem, but it would be the spring that pushes down on the lever, It may have been weakened and it is not providing enough downforce to the lever to keep it in's it's proper place during firing. I may be wrong but it's a thought. And seems like there was a brother on this forum who may have been making / selling them. Anyone out there know who that was?

I hadn't thought of the problem in those terms. I had the same issue. Replaced just about every spring in the gun. Works fine now. But that slide stop lever spring is a lot of fun. USE A PLASTIC BAG when assembling it! Trust me. You don't want to search around for that booger once it shoots off through the wild blue yonder.....

[snailman153624]

The spring stiffness doesn't reduce the felt recoil on an auto loader, and I'll explain why below. Also, A 22lb spring is producing 22 pounds off force per inch of spring compressed, not 22 lbs of force on the gun. As you stated, the impulse imparted on the firearm congress from the cartridge. The same amount of force is transferred whether you have a stuff during or a weak spring. The spring is just like a battery or capacitor...It temporarily stores energy as it compresses, but all of that energy is released when it decompresses.

In order for an auto loader to function, the slide has to go all the way back. A stiff spring will cause it to not go back far enough, so it won't cycle. A weak spring will cause it to slam into the stops, which will create the largest impulse in your hands, at the time when the slide hits the stop and there is no spring left to absorb the blow. This also can damage the gun long term.

So for that reason, I maintain that the only way to reduce recoil, while maintaining a reliable action and nit damaging the firearm, is to use a lower power load, coupled with a matched lower strength spring.

If it were nit an auto loader, but had a slide purely for absorbing recoil, then you would want the weakest spring that would just barely keep it from slamming into the stops. The idea is to maximize the time the slide spends slowing down, since impulse is the change in momentum divided by delta time. The momentum transfer is a constant for a given cartridge.

[Ketchman]

Snailman,
Is it not also true that it takes 22lbs of force to compress 1 inch of spring and that would it would indeed take 4 more pounds of force to compress a 22lb spring 1,inch than an 18lb spring 1 inch? and I also put it to you that that energy is absorbed by the recoil spring thereby removing some of the recoil energy generated by the ignition of the round from being transferred to your hand, thereby lessening "felt" recoil?

[snailman153624]

The spring absorbs it, and re-releases it. It has very little if any measurable damping.

Yes, it takes 4 more lbs of force to compress it 1 inch. Since you are shooting the same loads hence have the same amount of force from firing the bullet, it will compress less (the spring compresses until there is a force balance...same force on a stiffer spring means it will compress less), meaning it won't cycle, or the original spring was too weak, and it was slamming into the slide stops before.

Technically, a stiffer spring on a blowback pistol will keep the breach closed longer, meaning it will probably maintain higher pressures for a longer period of time, imparting more force to push the slide back.

[zardoz]

When I changed to a 22# recoil spring the kick didn't seem as sharp. It appears the stronger spring spreads the recoil out over a longer period of time. Same force but more of a push than a punch.

Jim

[snailman153624]

Which implies your original spring was allowing the slide to hit the stops pretty hard, meaning it was too weak for the ammo you are using.

[robhic]

Robhic,
If your slide hold open lever repair does not work you may have a spring problem, but it would be the spring that pushes down on the lever, It may have been weakened and it is not providing enough downforce to the lever to keep it in's it's proper place during firing.

That spring seems fine, IMO. The lock-back lever is raised, it's just that being bent that tiny bit INward is causing it to jump off/slide off the ridge around the bolt face where it is supposed to contact the slide to hold it back. In doing so the lever pinches this ridge between itself and the ridge. (look in your pistol with the slide locked back and you'll see the lever resting against this raised portion of the slide - holding it back)

In this pistol, the slide is off to more of the center of the gun and is pinching the slide which makes it difficult to pull back to reload. I bent the lever back more straight so it should NOW come in contact with the point on the slide where it is designed to contact and not slip off to the side. I also thought maybe a higher power recoil spring might cushion this backward movement of the slide so it wouldn't hammer the slide back and allow the lever better opportunity TO be forced to the side. I don't care about recoil "impulse" or whatever. I'm just trying to make the lever hitting the slide to stop it a bit easier to accomplish, that's all.

[Ketchman]

Well I hope that your fix is the fix the makes it right. Let us know.

[robhic]

And seems like there was a brother on this forum who may have been making / selling them. Anyone out there know who that was?

It's member Norm Sutton. On the first, title page for the forum he has his ad for trigger springs and slide-stop springs. $6 shipped and he takes PayPal. Can't beat it!!!