I don't own the quantity of 3rd gen's that some folks have collected over the years, as I was only looking for some smaller off-duty additions now and then, but I have a fair representation of that category.
I own a 3913, CS9, CS45, 3913TSW (late production), 4513TSW (original cutaway grip frame), 4013TSW and 4040PD.
The newest 3913TSW has seen the least amount of use, as it was only pulled from inventory (in NIB/unissued condition) to replace my issued 4513TSW a couple of years ago. I bought it when we were given the opportunity to buy one previous duty weapon, but I doubt it's seen more than a thousand rounds (if that) in the short time I carried it before it was replaced with an issued M&P40.
The 4040PD has seen the next least amount of range time, probably totaling no more than 2K rounds fired (it spent a long time in the safe from when I bought it in '05, and then decided to get it out and start shooting it again a couple years ago).
I've done a pretty fair amount of shooting with my other 3rd gens over the years, as they often replaced my issued weapons for range sessions when I was working as an instructor (and I'd get bored shooting the various issued weapons all the time).
I suspect my original 3913 ('98 production?), 4013TSW and my CS45 have seen the bulk of rounds fired over the years. At least a few thousand rounds each (and I was trying to wear out the CS45 for a few years
).
I've done some preventive maintenance replacement of springs over the years, and some occasional replacement of older parts with newer, revised parts (just because I could, as an armorer), and had probably a mag spring go a little too long before replacement at one time or another (like in the CS45), and I've periodically done armorer inspections of all of them.
However, aside from a sear spring pin in the 4013TSW having to be replaced (due to something I'd stupidly done to it), I haven't really had to dip into my spare/repair parts collection over the years.
A close friend of mine (another retired instructor) has owned a few 3rd gen's, which he shoots a lot more than I do, because he lives in the low Sierra's and built a range on his property many years ago.
He did manage to have an original 3913TSW frame develop a weird crack at the front of the frame dustcover, which the factory said was a weird place and rare. It happened at somewhere between 12-15K rounds, and they replaced the gun with a new 3913TSW.
His new 3913TSW is now many years old, and he said he likes to shoot it a lot, like almost everyday. I can't force him to keep it clean ... but I did give him a supply of new factory recoil springs a few years ago and told him to replace the spring at least every 5K rounds fired.
A few months ago he brought me the now very well-worn 3913TSW for an inspection, and I noticed the extractor had a small chip in the hook's edge. Now, S&W 3rd gen's have often been reported to function normally even with chipped extractors, but a chipped extractor is a chipped extractor ... so I filed and fitted a new one for the gun (and replaced the extractor spring with a new one that gauged out in the normal range on the force dial gauge). Test-fire of the replaced extractor confirmed feeding & extraction was, as expected, normal.
He's hard on his guns, though. HARD. Borderline (
) abusive.
I found chunks of
sawdust inside one of his SW99's one day, and he just shrugged and said he'd been wearing it while doing some fence work, but that the gun had fired and functioned just fine before he'd brought it by for an inspection.
I had to replace the ejector (molded into the sear housing block of the 99's) in one of his full-size SW99's back several years ago. As best he and I could guesstimate, he'd fired in excess of 52K through
that SW99 before the ejector broke.
Bottom line, the 3rd gen's are pretty robust, reliable and durable guns. The 9's and .45's generally seem to run longer, with less wear & tear, than .40's, but the .40 is hard on guns.
Keep them clean and lubed (especially important with the aluminum frames), and don't be stingy about replacing recoil springs. As was observed by an armorer instructor in a Glock class, fresh (recoil) springs help keep guns alive. No need to let them become battered.
