Questions about magazines and ammunition

[Sparky]

Can you keep a magazine loaded for an extended period of time (say, more than a year) and expect it to be reliable, or will that adversely affect the tension required for reliable performance?

Can loading and reloading the same bullets (say, a few dozen times for practice) affect the integrity of the cartridges, since each time they are loaded and unloaded they experience some amount of contact stress, particularly on the rims?

[mightymanx]

The magazine spring on a quality mag will not be affected but the feed lips can be stressed if it is that style of mag. This is why magpull for the AR mags has a cover that squishes the bullets down to take pressure off of the feed lips during storage. I have ready service mags that have been loaded for years with no ill effects. Now if you buy a cheap ass ghetto mag it might be a different story.

The second one is a no. The cases can be reloaded and shot several times. They are much tougher than you think now denting them is a no no because it can cause spikes in case pressure when it is shot.

[Sparky]

...
The second one is a no. The cases can be reloaded and shot several times.
...

Just to be clear that you understand my question, I don't mean shot and then reloaded with powder. I simply mean taken in and out of the magazine many times before they are actually fired. I find that loading a magazine is more difficult than it should be as the tension increases with each bullet, to the point where the rim of the bullet being loaded is taking all the pressure of forcing the stack of already-loaded bullets downward. My magazines are relatively new and so the spring tension is very high. I've assumed that this decreases with usage; is that correct?

[JJ.G0ldD0t]

Just to be clear that you understand my question, I don't mean shot and then reloaded with powder. I simply mean taken in and out of the magazine many times before they are actually fired. I find that loading a magazine is more difficult than it should be as the tension increases with each bullet, to the point where the rim of the bullet being loaded is taking all the pressure of forcing the stack of already-loaded bullets downward.

I've never heard of a problem where cases became overstressed b/c of loading the round multiple times.

I do it quite often :rolleyes:



My magazines are relatively new and so the spring tension is very high. I've assumed that this decreases with usage; is that correct?

Yep... they'll soften up. Eventually.....

[TheNocturnalEgyptian]

The way I am to understand it, is as follows: Strength of the spring is only reduced after numerous compressions and recoveries. One long compression doesn't put very much more wear and tear on the spring than one short compression. It is more about repetitions than about time. Source: someone asked this question on the old site, and this is what I remember.

I think the answer is going to be, "yes you can expect it to fire."

[Gaillo]

Mechanical Engineering perspective: Springs are designed to have a "range" of compression, within which the spring will NOT take a "set" or lose its "springiness". Modern, well-designed magazines and other gun springs are designed within this range, and will not deform or lose springiness over time.

Case in point: When I sold my last Glock 22 several years ago, I went through my old gun stuff to see if I had any accessories for it to sell with the gun... I found a fully loaded 15 round magazine I had forgotten about, and left stored in a box of gun things during a move. Since the move in question was over 10 years before that point, I knew the magazine had been loaded for at least 10 years. Just for laughs, I went out to the back yard and shot it all, then reloaded the magazine and shot it all again. Everything worked perfectly, the storage time hadn't affected the magazine spring at all.

[AndreaGail]

I had been curious about the same thing

Thanks Sparky for startin this topic and everyone else for their responses!

[mightymanx]

Just to be clear that you understand my question, I don't mean shot and then reloaded with powder. I simply mean taken in and out of the magazine many times before they are actually fired. I find that loading a magazine is more difficult than it should be as the tension increases with each bullet, to the point where the rim of the bullet being loaded is taking all the pressure of forcing the stack of already-loaded bullets downward. My magazines are relatively new and so the spring tension is very high. I've assumed that this decreases with usage; is that correct?
Unless practicing with the ammo is carving the brass where you have shavings, the acual firing is orders of magnatude more harsh on the case including the rim.

[horseshoe3]

I'm a mechanical engineer and I agree with Gaillo's conclusions. There is no reason a properly designed spring will "take a set". Fatigue would be more likely to cause a failure than creep.

HOWEVER, BX3 from GIM has a lot of experience with guns. He insists that he has seen magazine springs fail from staying loaded over time. I questioned him pretty hard on other possible causes and he still claims that none of those were present - it has to be spring set.

Take that for what you think it's worth.

[Dogman]

I'm a mechanical engineer and I agree with Gaillo's conclusions. There is no reason a properly designed spring will "take a set". Fatigue would be more likely to cause a failure than creep.

HOWEVER, BX3 from GIM has a lot of experience with guns. He insists that he has seen magazine springs fail from staying loaded over time. I questioned him pretty hard on other possible causes and he still claims that none of those were present - it has to be spring set.

Take that for what you think it's worth.

I agree with Gaillo, if the spring is designed and properly tempered they will last for a long time, how ever I do not care how well designed and made, if it moves ,it will wear or fatigue in time. It is the nature of the beast, but in Mag's it is something else that goes wrong, like being dropped , screwed up and hard use, etc. That will cause the mag to develop problems and has to be replaced, before the spring will fail, if it was made to spec's.

[TheNocturnalEgyptian]

Man, I miss Bx3. What a great poster.

[steyr_m]

Man, I miss Bx3. What a great poster.

Where's he at now? GIM2?

[steyr_m]

I agree with Gaillo too. There's a part of me that still takes apart my PMAG's while storing them to keep the springs in good shape.

[horseshoe3]

Where's he at now? GIM2?

Last I knew he was, but I haven't spent much time there in over a year. He didn't post on the deuce as much as on the original.