How full do you keep your AR Spare mags?

[Bug44]

I was always told if you are storing a loaded mag, regardless of what it is, ya never fill it to maximum capacity. I was told this will ruin the spring if it sits for a long period. So I normally load up my 30 rnd AR mags to about 25 rnds... Will this help in slowing down or nullifying the spring failure point?

What do you all do?

[streaker69]

I don't listen to internet rumors about metallurgy.

Spring failure occurs to do cycling of the spring. Constant compression does not ruin them. The reason why some people load them -1 or -2 is because it's supposedly easier to slap it in and have it lock when it's done that way.

But what I said could just be another internet rumor.

[bohound]

Agree with Streaker69... I keep my Pmags loaded at 26, and throw the keeper tabs on top while stored.

Keeps the feed lips safe. No worries about the spring whatsoever- I only unload when I shoot!

[DucatiRon]

I use Vietnam era 20 rounders which are loaded to the max. The few 30 rounders I have are loaded -1 because I do think it helps to load them in the gun and strip off the first round. My 30 rounders are generic in all terms of the word.

[bortle]

A little off topic, but I keep 20 rounds in my 30 round AK mags. That way I use 1 box per mag. It's a little easier loading too. If the SHTF I would max them out.

[fletchfletch]

A little off topic, but I keep 20 rounds in my 30 round AK mags. That way I use 1 box per mag. It's a little easier loading too. If the SHTF I would max them out.

I do the same with my AR mags

[ChamberedRound]

I was always told if you are storing a loaded mag, regardless of what it is, ya never fill it to maximum capacity. I was told this will ruin the spring if it sits for a long period. So I normally load up my 30 rnd AR mags to about 25 rnds... Will this help in slowing down or nullifying the spring failure point?

What do you all do?

It's my understanding that the problem isn't the follower springs, as they can stay compressed for long periods. However, the force of the top round in a loaded magazine pushing up on the feed lips can potentially cause deformation over time, causing feeding problems with the magazine.

As bohound said, Magpul's attempt at addressing the issue with feed lips on the P-MAG was to provide a tab that snaps on to the top of the magazine, slightly pushing down on the top round when in place, and taking the pressure off the feed lips.

I'm not sure if any type of "keeper tabs" similar to the one for the P-MAGs exist for the GI mags.

[csmith]

PMAGS full with caps on

[Wildbill990]

I have 8 pmags fully loaded and 3 gi mags fully loaded. Spring is weakened through cycling so I'm not worried about that. Pmags have the dust covers like others said that protect the lips. Gi mags don't and that's the only ones I'd worry about however the 3 I have are just about never used since theyre full of hp for the house.

[Valorius]

Filling a mag does not weaken the spring. It's cycling the spring that weakens it. Ie, loading and unloading it (as is done when you fire the weapon).

With AR's i always kept 'em loaded to 30rds. Some will say that it's good to download to 28 to relieve the pressure on the feed lips, but i've never had such problems.

On my FsN 5.7mm pistol i download my mags to 28 rds only because the 30rd mag extensions have a seam where they join with the FN factory 20rd mag body. When the follower moves past this seam it hangs up sometimes. So as long as you download to 28 or less, the follower never crosses the seam, and the mag is 100%.

So...it depends on the platform as well.