My wife bought this gun about two years ago an put two or three thousand rounds (maybe a little more) down range without any failures. She has used just about any ammo that you could name, except high price competition stuff. About a month ago the weapon decided it no longer liked Federal Automatch (325 box).Repeated stove pipes, ftf, and fte per magazine. It didn't seem to matter what lot number we tried, it wouldn't properly cycle any of them. This is a problem because we have a boat load of it.

Shortly thereafter it started turning its nose up at CCI SV. It would cycle and fire without problems, but would not lock back on the last round. Not a big deal since we only have a couple of hundred rounds.

It thrives on CCI Mini Mag 40 grain, 36 grain HP, and the AR Tactical. I have a lot of this stuff so that's good. Still, I'd like to be able to get through our stash of the Automatch.

I called S&W CS three weeks ago and explained the problem and they sent me a shipping label. The gun went back that day. I should have it back in a week or two, hopefully cured of its bad behavior.

Has anyone else on the forum had a similar problem? It seems odd to me that it would suddenly develop an aversion to ammo that it had a taste for in the past. The gun is carefully cleaned after each use and oiled as per the manual. Can I expect it to behave or is it time to trade it in on something new?

Thanks for any input.

Just a guess but seems the ammo thats causing issues is lead round nose while the plated ammo is ok. Could there be something tied to lead buildup? Again probably off base but thats the only thing that popped up in my head.

The CCI Mini-Mags and AR Tactical is high velocity ammo. All the stuff your gun doesn't like anymore is standard velocity, and sends the slide back with less force. It therefore goes back forward with less force.

Since your gun worked OK with this ammo for 3,000 rounds, it seems your recoil spring was still had enough force to rack a round and push the slide into battery.

Now, after 3,000 rounds, your recoil spring may not be strong enough. I expect the recoil spring will be the first thing S&W changes, and just might solve your issue.

Here's hoping for a good outcome.

I’d agree that it’s probably the spring. That, and some of the ammo turned out during the late unlamented shortage was junk. Did it work well with that ammo before?

The gun gets meticulously cleaned after each use so I don't think it could be a leading problem, but maybe it is. If so, how do I avoid this from happening again?

I never thought of a weakening recoil spring. Should that happen after only 3000 or so rounds?

I wouldn’t think so, but stranger things have happened. A new spring is a cheap way to find out for sure.

I have seen this happen with the recoil spring incorrectly installed, and from stiff, cold grease (different guns). Use oil or light grease, and be sure to get the face of the hammer.

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