Rotating Mags?

[Steely Dan]

Every two weeks I load one mag for my MP 40 and empty the other to prevent constant spring tension (its stored by my bed as my SD). Does it matter? Will it hurt to constantly have the Mag's loaded? Will it weaken the mag spring over time? Thanks SD

[shield]

No problem to keep loaded.

See discussion at end of this thread:

Storing Mags

[Fabius]

See the thread linked above. Cycling the spring will weaken the spring over time. Leaving it loaded is better.

[Steely Dan]

Thank you for the link. I feel like an idiot for asking now but I am new to semi autos and I always try to take care of what I have spent hard earned money on. Thanks SD

[Fabius]

Perfectly legitimate question. I had the same question years ago when I bought my first pistol. Worried about it then. Now, after years of leaving my mags loaded, I don't worry about it.

[danysw]

Nobody is idiot for asking..... for not asking yes.

[WR Moore]

While it doesn't hurt to rest magazines, yearly is sufficient. The factory recommendation is to replace mag springs (and some other minor stuff) at 5 years. I don't believe we bothered since there haven't been any issues.

BTW, not having a spare loaded mag can present major problems should you have a malfunction and need to discard the mag in the weapon. Feeling around on the floor in the dark for a mag isn't conductive to a long happy life.