DPris said:
Springs most definitely can & do take a set.
My department armorer used to R&R Glock springs on several pistols during annual inspections, rotating around among inventory being carried.
- A problem I've experienced with hollow points is that some feed ramps and some of the "mouths" of some hollow points don't get along -- and the "maw" of the round digs into the feed ramp. I found the same thing recently, when running some 9mm hollowpoints through a 9mm conversion barrel in my FNS-40 using the .40 mag. Hardball wasn't a problem, but hollowpoint wouldn't work -- because a 9mm round in the .40 mag sets just a bit higher and hits the feed ramp at a different angle. I eventually bought a couple of 9mm mags for when I used the conversion barrel.
- Another issue is that if the springs in the mag are too stout, and you're trying trying to cycle a full mag, the pressure (and friction caused by) of the top-most round pushing up against the bottom of the slide for the first round keeps the slide from coming forward properly. One solution is to polish the underside of the slide. Some guns that are 7+1, 8+1, or 10+1 really do better if you ignore the +1.
Re: Spring life and spring damage.
danez71 and I have been involved in a number of discussion on this topic on this and other forums over the past several years.
As he notes above, springs can degrade from more than cycling. It all depends on the way the spring is put to work by the gun's designer. As
DPris also notes above, coil springs
take a set almost immediately upon being put into use. Gun designers know this and take it into consideration when specifying the type of springs to be used. (I hate to buy a new Glock mag, as I always feel I need a bumper jack to load the darned mag. ) Over time, however, they become easier to load.
In the discussions mentioned above, on both this forum and
The High Road, we had metallurgists (engineers who specialize in putting metal to work) and other engineers who work with springs, address what degrades springs. Surprisingly, it's the same things that degrades metal, aluminum, wood, rubber, glass, etc., etc. -- pushing or pulling the material past it's elastic limit.
The explanations these experts have offered (substantiated by many tests and evaluations as well as many technical links to professional sources ) is that if a spring is pushed to or beyond its
elastic limit, the metal will begin to suffer micro-fractures and slowly lose it's ability to do work. In fact, cycling won't necessarily do a lot of damage unless, during the cycling, the spring is compressed deeply enough to reach or exceed it's elastic limit. Cycling alone isn't what causes the damage. DEEP cycling does it. That's why recoil springs and mags spring go soft but seldom break -- they're replaced when the can no longer work. Leaf springs tend to be worked longer, and while they can degrade, they often break.
As noted, the springs in a 7-round 1911 mag almost never wear out -- even if left loaded for 40+ years. These were designed with a lot of reserve power, and when fully loaded they never come close to their elastic limit. Seven rounds were considered ENOUGH when JMB designed the 1911. But, when springs are pushed too far -- recoil springs lose the ability to close the slide fully, and some mag springs can't lift a round high enough to be caught by the slide. (I once had all of the rounds in magazine fall onto the floor when the mag was turned upside down -- the spring didn't have enough force left to keep the topmost round pressed against the top of the mag's feed lip. Most 10-round 9mm mag springs in full-size guns may last about as long as a 7-round 1911 mag spring.. But some of the 18+ round 9mm mags will have problems, particularly if they are left fully loaded for long periods. (Wolff Springs suggests downloading mags a round or two for long-term storage -- but not all mags need it. They also talk about elastic limits on their site.)
The recoil springs for a Rohrbaugh R9 have a recommended service life of only 250 rounds -- although they'll likely last longer. But, If only cycleing a recoil spring, why does 250 cycles begin to severly degrade) a R9 recoil while other recoil springs go on and are never replaced? (Most of the recoil springs for compact or sub-compact guns have shorter service lifes than related full-size models.) Different gun designs ask different things of the springs in their guns. With some of the newer smaller guns, or some of the guns with mags that have very high capacities, the springs are, in effect, viewed as renewable resources by their designers -- and by the people who own the guns.
What damages a recoil spring or a mag spring is if the spring is compressed too far. Leaving it compressed too far simply accelerates the damage -- that compressed spring is, believe it or not, working even when it isn't cycling. If the spring isn't close to it's "design"/elastic limit, keeping a mag fully loaded or cycling it thousands of times will have little effect on it's service life, because the spring isn't being pushed too far.
With many designs, the springs never get compressed far enough to cause damage to the metal, but with some of the newer hi-cap mags, and with some recoil springs in very small guns (like the Rohrbaugh R9), spring life is much shorter than what most of us have come to expect.
