Do you load your mags to full capacity?

[DaveM55]

No dumbing down for training, EVERYONE needs training. Even after 100's of hours of professional instruction and 1000's of hours runnings drill, there's still a need for more training.

My point is that training for a real handgun combat situation on the street it is good to consider you may lose some motor skills. Evening handling a pistol magazine may present problems for some during a fight. So to make things easier and more reliable, (not a dumb thing to do) it was suggested to me to down load my backup Glock 21 mags -1.

[Sigchaser]

What actually wears a spring is a constant movement. What that means is that loading to capacity is fine but loading and unloading everyday isn't. The springs in a fully loaded mag should be fine.

[ungawa]

Originally Posted by TonyF

That doesn't surprise me. Lots of magazines in U.S. >mil inventory that should have been destroyed and replaced long ago.

Amen to that!

If you're referring to P-Mags, yes they have more "space" but most professionals I know still prefer USGI magazines.

I'm not surprised. I had a P-Mag malfunction when the rounds in the stack lined up all goofy under full auto fire. Does this prove anything? No. But I looked at it, said "WTF is this?" and then decided I'd just go with what I know.

[headcase]

Originally Posted by TonyF

M16 magazines should be downloaded by two rounds.

20's - 2 = 18

30's - 2 = 28

The reason is that with magazines loaded to capacity there isn't enough space in the mag body to seat the magazine on a closed bolt due to the increased compression from the underside of the BCG impinging on the top round in the magazine.

The reason for downloading by two rounds is so that "crossover" remains consistent.

I don't doubt "some of you" can seat "some of your magazines" loaded to capacity on a closed bolt. That is a combination of your rifle's tolerance stack wedded to a fatigued magazine spring.

Don't bother arguing with me about it because I'm not going to play. I've lost count of how many fully loaded, poorly seated, "dropped" magazines I've seen in training classes over the years.

People pay good money for this kind of information.

ETA: You can load your pistol and M-14 mags to capacity.

Exactly on the money, not a thing to add.

[Sir Knight]

Well, it appears that I am swimming against the tide on this one but according to Wolff (who, I would HOPE, knows a thing or two about springs) ...

Magazine springs in semi-auto pistols are one of the most critical springs and the subject of much debate and concern. Magazines which are kept fully loaded for long periods of time, such as law enforcement applications, will generally be subject to more fatigue than the weekend shooter's magazine springs which are loaded up only when shooting. Magazine design and capacity also affect the longevity of the spring. Older designs where maximum capacity was not the goal such as the 7 round 1911 Colt magazines will last for years fully loaded. There was a lot of room for a lot of spring which reduced the overall stress on the spring. In recent hi-capacity magazines, the magazines were designed to hold more rounds with less spring material. This puts more stress on the spring and will cause fatigue at a faster rate. Unloading these magazines a round or two will help the life of the spring. Rotating fully loaded magazines will also help the problem somewhat but is not always practical. In applications where the magazine must be kept loaded, a high quality magazine spring such as Wolff extra power magazine springs, will provide maximum life. Regular shooting will verify reliability and regular replacement of magazine springs will provide the best defense against failure from weak magazine springs.

... http://www.gunsprings.com/Resources/FAQ.htm#5

[Lycanthrope]

I use Wolff springs. They sell a lot of springs.....

Here is the best spring resource I have ever seen:

http://www.brianenos.com/forums/index.php?showforum=28

Lycanseriousthoughtthrope

[LittleRedToyota]

Originally Posted by Sir Knight

Well, it appears that I am swimming against the tide on this one but according to Wolff (who, I would HOPE, knows a thing or two about springs) ...

you would think, wouldn't ya? but what they are saying seems to contradict physics.

here is an article about it in relation to magazine springs.

http://findarticles.com/p/articles/m...27/ai_99130369

To put this one to rest, you have to understand creep. Creep is the slow flow of a non-ferric metal like copper, brass and lead under force. At temperatures outside of a furnace, steel doesn't have any appreciable creep. Under most conditions, steel flexes and then returns to its original shape. When pushed past its elastic limit, steel will bend and not return to its original shape. All designers of well-made magazines make sure the spring never approaches the elastic limit when the magazine is fully loaded. Honest. This means the spring will not weaken when the magazine is fully loaded -- not even over an extended time. Like 50 years. American Handgunner recently ran a story about a magazine full of .45 ACP that had been sitting since WWII and it ran just fine on the first try. So there you go.

i used to have a link to a scientific paper talking about spring fatigue/creep/elasticity/etc. in general (not related to guns), but i can't find it at the moment. i will keep looking and post it when i do.

[Mtbkski]

Do I carry to capacity??? Heck I purchased 40 cal mags for my Subcompact XD9 and tweaked them so they hold 12 rounds of 9mm each. This gives me 13 rounds available in a loaded handgun on my hip in a very small package. And another 12 close by in another mag.

Does this magazine capacity thing apply to AK magazines as well?

[Jup06]

Originally Posted by LittleRedToyota

you would think, wouldn't ya? but what they are saying seems to contradict physics.

here is an article about it in relation to magazine springs.

http://findarticles.com/p/articles/m...27/ai_99130369



i used to have a link to a scientific paper talking about spring fatigue/creep/elasticity/etc. in general (not related to guns), but i can't find it at the moment. i will keep looking and post it when i do.

Theres a lot more going on in a spring than most people realize and even engineers can’t predict their behavior 100% of the time. For most purposes steel generally has no creep. Imperfections in the surface and within the crystalline structure can all cause stress concentrations that can cause a spring to fail prematurely. When the manufacturer is working with a low factor of safety (maximizing profits) this can become an issue. I’ve heard people argue that mag springs do not take a set but these people have never measured one with a caliper. All springs will take a small set and get worse the longer the spring is loaded. While this may not effect a 7-round mag, there have been instances of FTF's with the last round of a high-cap mag.

I’ve also seen cheapo spring steel parts start to loose their temper (and strength) at 160F. I believe Wolff pegged it though when they referred to the hi-cap mags being the main problem. A lot of hi-cap mag springs do not have linear rates either, which complicates things. When subjected to cyclic fatigue loadings there are plenty of charts one can refer to and get an idea of how long a spring will last . I’d throw some formulas up for you guys but they would be unreadable without LaTeX. In the end, it’s pretty cheap to replace a mag spring if you suspect it is shot.

[LittleRedToyota]

Originally Posted by Jup06

When subjected to cyclic fatigue loadings

right, but we aren't talking about the spring being cycled (or at least i don't think we are). we are talking about a carry mag being loaded and left that way...or at least that's what i was thinking of.

at any rate, the cycling will have the same effect (or lack thereof) whether you load it to capacity or not, right? you are still cycling it.

also, i am assuming that the magazine is designed in such a way that loading it to capacity does not push the spring to its elastic limit.

i'm curious, does your analysis apply if the magazine is not cycled and if the assumption about not reaching the elastic limit holds?

In the end, it’s pretty cheap to replace a mag spring if you suspect it is shot.

absolutely.