Magazine Tune-up

[buckhorn_cortez]

I cut one coil off the mag spring on each mag and they seem to work fine. Guys I shoot with said I should throw them out. They work fine so I am using them.

If they work...why throw them out? New ones aren't going work any better than ones that already are working.

The only thing you may find is that, after a while, the slide may not lock back because the spring has been compressed enough from use that the follower is either, not going up high enough, or not hitting the slide lock with enough force to lock the slide open.

In that case - new springs, and if the follower is worn, a new follower and you're good until you have to replace the springs again.

The only time a magazine tube need to be discarded is if the feed lips are cracked. Some feed lips will get bent further open through use. This will cause multiple rounds to feed because they're not being stopped in the tube by the feed lips.

Your choice is to bend the lips inward very slightly so the rounds are stopped in the tube or discarding the magazine. The problem with bending the feed lips inward is that you're working the metal and weakening it, so you end up having to bend them in at shorter and shorter intervals until cracks start to appear.

Many manufacturers now offer a lifetime warranty on the tubes. Springs and followers are wear parts that are meant to be replaced when you encounter malfunctions caused by wear - generally not locking the slide open.

 

[Onward Allusion]

If you lighten your striker spring to lighten your trigger, you may need to "tune" your mag by increasing the strength of its spring because cycle time would be faster. . . and possibly vice versa with increasing pounds on the recoil spring. Nosediving cartridges is an indication of mag spring strength not matching recoil/hammer spring.

Another example might be using a 33 rnd mag in a G26 or a 15 round S&W 59 mag in a KT P11.

 

[Walt Sherrill]

If you lighten your striker spring to lighten your trigger, you may need to "tune" your mag by increasing the strength of its spring because cycle time would be faster. . . and possibly vice versa with increasing pounds on the recoil spring.

The striker spring affects how HARD the striker hits the primer (and, in some models, the force required to release the striker). The gun's firing cycle doesn't begin until the striker or hammer is released and the firing pin or striker hits the primer! (With some guns the slide's rearward movement will partially recharge the striker spring, but that's a trivial amount of force redirected; the same is true with some SA or DA/SA guns in that slide movement partially or fully charges the hammer spring.)

If you take too much force away from either of those springs by cutting and shortening the spring, you may get a lighter trigger or weak primer strikes. Cycle speed will be more-directly affected by the ammo and recoil spring used -- and indirectly by the hammer spring. I would argue that a striker spring has far less effect on slide movement than a hammer spring, and lighter springs in either case aren't as important as recoil springs or the ammo being used.

Nosediving cartridges is an indication of mag spring strength not matching recoil/hammer spring.

In all of the cases I've seen or experienced, nosediving typically occurs when:

1) the magazine spring is installed incorrectly (so that the front of the follower isn't properly supported, or

2) when the mag spring itself doesn't have enough resilience/strength left to hold the follower UP (to allow the round being stripped from the mag to be fed onto the feed ramp), or

3) when a damaged follower might screw things up -- not often seen until the last round in the mag. (This may not cause a nose-dive, but it might also not feed properly.)

There may be other causes for nosediving, but they don't immediately come to mind. That said, I've been known to overlook the obvious.

.

 

[Onward Allusion]

For sure regarding hammer springs. Striker spring depending on whether it's partial or full reset.

RE: Nose-diving, yes to all of what you stated. I first learned about the mag spring to cycle time by using factory 5906 mags in a Kel Tec P11.

 

[JohnKSa]

If you lighten your striker spring to lighten your trigger, you may need to "tune" your mag by increasing the strength of its spring because cycle time would be faster. . .

The only part of the cycle time that could possibly be affected by striker spring weight would be the last 0.5 to 1 cm of forward travel when the striker is being pre-loaded by the slide action.

Theoretically a lighter spring would mean faster travel, but given the small amount of time that it could affect anything and how late in the feeding cycle it occurs, I can't imagine that it could make any practical difference in how the gun feeds.

In a hammer fired gun, a stronger hammer spring provides a retarding influence (and sometimes a significant one) right at the beginning of the rearward slide travel. I can see that a significantly stronger hammer spring might make a difference in slide velocity, but even then I would think it would be a relatively small difference.

 

[buckhorn_cortez]

In a hammer fired gun, a stronger hammer spring provides a retarding influence (and sometimes a significant one) right at the beginning of the rearward slide travel. I can see that a significantly stronger hammer spring might make a difference in slide velocity, but even then I would think it would be a relatively small difference.

Very true, and on a 1911 / 2011 style pistol, the shape of the bottom of the firing pin stop (square or rounded) has about as much effect on retarding the rearward slide velocity as the strength of the main spring.

There a lot of things that are interactive and it's hard to single out one facet as being "the" main factor.

 

[SGW Gunsmith]

Bending Feed Lips=Ruined Magazines

+3, 4 +5.


I tune & smooth magazines all the time, especially the stamped versions that Ruger sells for the Ruger Mark pistols. Used as is, the follower button will not run well with all the burrs left behind from the stamping die in the follower button track. Also, the sharp inside edges of the feed lips will shave particles off the cartridge case as a round is fed toward the chamber and deposit those shavings in the receiver or chamber. When bad enough, those ragged edges, when present, can impede a fresh round from entering the chamber properly, smoothly and quickly.

I just LUV to compete against those who don't take the time to prep their magazines so they run as best they can. Gives me an additional edge.

 

[T. O'Heir]

Bending mag lips(there is no 'feed' lip) too much equals ruined magazine. Adjusting mag lips does not always ruin magazines. Tool is fine long needle nosed pliers and tweaking vs bending.
However, as mentioned, there's no such thing as tuning a mag. Mags either work properly or they don't.
"...all the burrs left behind..." That is a factory QC issue. Any thing with burrs still present should be returned for replacement.