Confederate said:
...Well...maybe they learned something about gun safety, too, but it's a good thing it jammed. For people who shoot a lot, they replace them every few thousand rounds. But if it came down to it, how long would most recoil springs continue to function if shot a hundred times per month? Three thousand rounds is most likely an arbitrary "safe" number for changing springs, what if push came to shove?
This has been discussed at great length on this forum and The Firing Line, with experts and a metallurgist or two involved in the discussion.
WORKING a spring will cause wear. Leaving a spring compressed can (not WILL) cause wear. In either case, it depends how close to the spring, when compressed, is to that spring's design limit -- called it's
elastic limit. If a spring never gets compressed to its elastic limit, it can live a very long life. If the spring is greatly compressed (and reaches or exceeds that design limit), as is the case with some hi-cap mags and small guns, the spring may not live as long. Leaving a hi-cap mag fully loaded can accelerate spring wear with some mag designs, but not all. (Wollf Springs recommends down-loading a round or two for long-term storage.) Mags from WWII 1911s have been left fully loaded for many decades and continue to function properly; those springs are never pushed close to their elastic limits.
Some of the new smaller gun designs push springs farther than ever they've ever been pushed, and there's no free lunch...for THOSE design, springs become renewable resources. Rohrbaugh recommended replacing the recoil spring for the R9, arguably the smallest truly functional 9mm pistol, every 250 rounds or so.
With some guns, like most full-size guns and guns that don't have hi-cap magazines, the recoil and magazines springs may outlive the gun and owner. With compact guns and sub-compacts, spring life may be greatly reduced (ala Rohrbaugh R9). Some full-size 9mm guns may never need a recoil spring replacement -- it really depends on the gun's design, how the springs are used, etc.
The owners manual or customer service at the gunmaker can give advice.
Because coil springs are, generally speaking, pretty inexpensive for most common handguns, most folks figure that's the peace of mind that comes from changing springs regularly is money well spent.
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