Seems to be a common problem with them. Try these guys...
I recently bought a Kel-Tec P3AT for CCW use. So far, with only 187 rounds through it reliability has been pathetic - 4-5 jams. I've tried 3 different brands of ammo. (100 Win w/ flat nose & 50 MagTech Ball & 37 Rem Ball) The accuracy is surprisingly good and I got used to having only 1.5 fingers on the grip but the reliability is an issue. As best I can tell, the fired round isn't completely being ejuected from the chamber, so the fresh round is jamming against the bottom of the fired case. Also, the assembly pin is backing out on it's own. Just a 1/16 or so, then I push it back in. That just started. On the last trip to the range, the slide doesn't feel right sliding it back, like it has a "catch" or rough spot in the slide. I have not cleaned it yet. That's my next step. Any other ideas?
My P3AT will jam occasionally with WWB, but never hiccups with Hydra Shok, so I'm not concerned about jams at the range with the cheap stuff. As far as the other problems, send it back to Kel Tec and tell them what's going on. I've heard their customer service is top notch and you have a lifetime warranty. They will fix the problem.
In addition to cleaning it, get some 600 grit sand paper and lightly go over the feed ramp and the chamber.
Also, work on keeping a very tight grip on the tiny little gun. Limp wristing is the primary reasoning for these kind of jams. It took me a while to get used to it, but have not have any problems since learning the feel of the gun's recoil.
To help you out again, go buy a bersa magazine and switch out the magazine baseplate. This gives you a much sturdier grip. After doing this, I was able to shoot one handed from the hip all 7 rounds and keep them within 8 inches at 6 feet. Ktog.org is also a great place for smithing info.
It take's a good frim grip on the little sucker to get it to work like it's suppose to.
Update: I carefully cleaned it. 600grit to the feed ramp and a few rough edges inside although I doubt if I did enough to change the jam issue. Made me feel better though. Called Kel-Tec today and was impressed with their Customer Service Dept. Spoke with "Bill" who said it was probably the extractor. When I mentioned the low number of rounds fired, he said that was irrelevant and he had seem them give problems from shot 1. He sent one out at no charge. I'll certainly wait for that arrival. I don't think I'm limp wristing it, although I'm open to ideas. I've shot enough to know better but that may not prove anything. Thanks for the ideas.
Glad to hear Kel Tec is continuing their great customer service reputation.
I'm assuming that you have a 2nd generation pistol; that said, while waiting for the new extractor, you might check that the screw which holds down the extractor spring is tight. If it's loose enough it can cause problems similar to a bad extractor. You will need a quality allen wrench (2mm) as the screw is somewhat soft (it's a good idea to get a few extra screws from Kel-Tec). That spring should have a slight arc to it. Some flat ones have been known to make it out to the field.
Update w/ Range Report: Apparently, my DIY gunsmithing worked out great. Just polishing the feed ramp and hitting the rough edges did the trick. Fired 130 rounds of mixed brands with no failures of any kind. All were round nose FMJ. Tried rapid fire also. I'm going to try some white-box Winchester from Walmart that has a blunt FMJ tip. If it can feed those reliably, then I'll start trying a couple of the self defense ammo types. Thanks for the ideas.
Thanks for the update and it's great to hear you got it up and running!
Great to hear you got it working well. I still haven't been able to shoot mine yet, but went ahead and polished the ramp like everyone else did. Hopefully I have as good of luck as you did.