Keeping mags loaded - spring fatigue

[H3baton]

It depends. If magazine spring was improperly heat treated, or cheap spring, yes it can mess up staying loaded. Also, watch out the feedlips of loaded magazines. Gen 2 PMAG and aluminum GI ar15 mags had feedlip issues when kept loaded.

[b18bturboek9]

Depends on if you set up for tactical reloads then I’d leave 28/29 rounds loaded in 30rd mags. If your worried about bbraw and reloading then max round count in mag. That’s how I’ve always saw it could be wrong but not claiming to know everything or be perfect just my 2cents.

[BrassCase]

This is why Magpul's (most) come with "dust covers". The covers presses down on the last round so that it isn't pushing against the feed lips.

As for loading magazines: Unloaded magazines are useless except as paperweights.

The harm that comes to magazine springs is in loading and unloading. Springs, like other moving items, have a cycle life. The easiest analogy to give is one I learned in a Strength of Materials class at college. Take a paperclip and bend it back and forth until it breaks, now you know it's cycle life for bending. That is a bit simplistic but the idea is that the movement, bending, causes fatigue. Fatigue leads to cracks in steel causing failures. Exceed the the fatigue life and you will see a failure. Airplane wings are subject to fatigue cracks and failures if they are left unchecked as an example. Airplane wings flex.

[buster1960]

Ok leaving them loaded is accaptable. Now let's say, I have worn out the original springs. Which is better, round wire or flat wire springs and, why?

[tawadc95]

I wish I had a dollar for everyone go has told me don't leave mags loaded but has never given a single worry to 1911 mainsprings being compressed for years while cocked and locked or striker springs compressed.

If you espouse mag spring old wives tales you have to be consistent about all springs.

[sonofeugene]

Ok leaving them loaded is accaptable. Now let's say, I have worn out the original springs. Which is better, round wire or flat wire springs and, why?

You will never wear out the original springs.

As for round or flat, ones as good as the other if designed properly. No difference except that flat wire prints are more expensive to make.

[buster1960]

You will never wear out the original springs.

I have a friend in Nevada who received 10 military 30 round steel AR magazines that were for range use. Possibly as many as 100k rounds through each of them. Would it be prudent to clean the mags and replace the springs and followers?

[GeeBee49]

I have a friend in Nevada who received 10 military 30 round steel AR magazines that were for range use. Possibly as many as 100k rounds through each of them. Would it be prudent to clean the mags and replace the springs and followers?

If they still function there's no need to replace anything yet. When the last round or two starts failing to feed that usually means the spring needs replacing.

[buster1960]

If they still function there's no need to replace anything yet. When the last round or two starts failing to feed that usually means the spring needs replacing.

Thanks, just thinking a spring and follower are $4. A failure to feed/fire could be much more!

[GeeBee49]

Thanks, just thinking a spring and follower are $4. A failure to feed/fire could be much more!

He should test them all a few times at the range before he relies on them for self defense.

[The War Wagon]

Ok leaving them loaded is accaptable. Now let's say, I have worn out the original springs. Which is better, round wire or flat wire springs and, why?

NEW springs.