Mag springs?!

Thank you Weldon...and Johnny, I had good customer sevice from HK...when I told them my 147s didn't feed the last round they told me to ship them back and I got new ones in 4 days...good luck with your P7...it's quite a gun....
 
2 thoughts on springs

1. Teddy Jacobsen (Actions by T) suggests taking your misfunctioning magazine springs out, stretching them from both ends simultaneously, then put them in a 350 degree oven for 30 minutes to "reset" the spring. I did this on 3 Chip M Shooting Stars, and it cured the "last round" problem.
2. A pistolsmith was telling me that the recoil spring is NOT designed to prevent battering of the slide. A recoil spring is designed to "recoil" from the open slide position, pick up a new cartridge and seat it, and put the weapon back into battery. He says that you only start a new chain of problems when increasing recoil spring weight. Like battering the link pin, the feet on the barrel, and the slide stop pin, cause they take the brunt of the action caused by the recoil spring. And, needing a stronger magazine spring to react faster when the slide IS open, etc. If increased power load battering is a concern, he recommends shock buffs, provided the notch on the slide is far enough back to insure the slide release mechanism will engage it with the buff in.
I thought about his ideas, and he certainly makes a lot of sense to me.
YMMV
Walt
 
45Colt

Those are some very good and valid points. I've always thought of battering ocurring as the slide recoils under the force of several hundred pounds of muzzle energy being generated - not as the spring closes the slide but I guess there is wear in both directions. Sure makes sense. I know I can hold the slide open against the recoil spring with my thumb and forefinger. It makes me wonder if I could hold the slide in the closed position with my thumb and forefinger as I touch off a round. I'll probably never try it, but I'm sure the recoil force has a little more steam behind it than the spring closing force and that's the one I'm trying to protect against in my alloy frame Beretta 92. Now I realize that protection isn't free, as I guess a little more wear is ocurring during the closing. Dang it. I'll probably be trying to analyze this for the next 3 months. In which direction is slide velocity worse?
My head is already starting to hurt.

After you remove the magazine springs from the oven do you let them cool at room temperature, quench them in water or just turn the oven off and let them cool gradually? That sounds like something I'd really like to try with some older springs I've got laying around.
 
Based on my knowledge of Physics I'd tend to agree with 45 Colt's pistol smith's remarks about increased power recoil springs.

Weldonjr2001 is correct in that the bullet recoiling backwards is greater than the force of the spring pulling forward. This is done for reliability reasons: If the spring were more powerful than the recoil from the bullet, the slide might not go back far enough, causing the case to not eject properly, or at all.

One could actually use a 2 lb recoil spring in the gun if the slide weighed enough. The gun might have slow follow-up shots though :-) The purpose is as stated before only to bring the slide back to its starting position by storing some of the energy created by the cartridge. A gun with a light weight slide, and a strong recoil spring would thus allow for the fastest follow-up shots... a gun like the P7... though the delay caused by the gas system might affect the time a bit I don't think it is a significant increase.

Another effect of the recoil spring... if my Physics are correct here would be to spread out the recoil of the cartidge. Any other Physics Pholks listening correct me if I'm losing it here.
A portion of the recoil is soaked up by the spring, but part of it (the part not eaten by the spring) hits going in the opposite direction of the bullet, hence hitting the front of the frame (where the motion of the slide is stopped when it strikes a piece of the frame). The rest of the recoil... is travelling in the same direction as the bullet is moving, when the slide snaps forward, and strikes the back part of the frame, but in the opposite direction of the previous force. This make sense to anyone else but me?

Oh... wait... hmm... all right whoever is following me I had another thought. When the slide is recoiling the spring is pressing against both the slide, AND the frame, the latter of which is pressing against your hand, creating something of a "slow and steady" recoil, rather than the snap that comes once the spring has stopped eating the recoil. Ahh... OK I'm pretty confident now. Anyway, anyone else wanna run this through their head real fast for me?

-Morgan
 
How about the possibility of a weaker spring and increased slide recoil velocity causing greater slide closing velocity due to the slide rebounding off the frame? We all know steel will bounce off steel due to its elastic nature. Anyway, a Beretta 92 doesn't have all that 1911 stuff going on inside. No link or link pin. The barrel recoils straight back until the locking block is cammed out of engagement. The barrel feet slide. There is a slide stop but I can't bring myself to worry about it taking much extra abuse due to increased slide closing velocity. In a 1911 that is the cheap stuff to replace as opposed to the frame. I'll keep an eye on my slide stop for wear now that I'm thinking about it. I know that when I went to +P the extracted brass was getting thrown a few feet farther. That did tell me I had increased slide recoil velocity thus increased wear on the frame, ejector and extractor. I have no real way of measuring slide closing velocity but I like the way I have the pistol set up now and feel comfortable that I have done the right thing. Time will tell.

CaesarI:

I had 4 semesters of physics (is it different if you capitalize it?) myself and agree with everything you say but you've got to admit that the manufacturers themselves put stronger recoil springs in guns of equal frame but snappier calibers. Browning puts a 3 lb. stronger spring + heavier slide in the .40 HP as opposed to the 9mm. Sig a 1 lb. heavier spring in the 229 in .357 Sig as opposed to .40 and so on. I'll go with the manufacturers (good ones anyway). I figure they've looked into the physics of things pretty well if they've been in business for a while.
 
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Standard Cap Mags?

I've only got the 15 rounders for a Beretta, but it would seem to me that a post-ban mag of 10 rounds would have a spring which was not fully compressed, and therefore capable of being carried fully loaded without running into the problem of having the last round hang up. Am I crazy or just a neophyte?


Check Six.
 
Don't sweat it...my 15 rounders stay loaded on my duty belt and always work fine at range time.....load it to the top and don't worry about it...in the worst case scenario of a last round not feeding, you wouldn't have had that round in the gun anyway so you still have the same number of shots.....
 
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