I should use only gun cleaners.
Whatever you do I hope it helps. If not, you have to know that Karh's customer service is excellent; just contact them and they will fix it for you.
Remember, manually racking the slide only affects the friction areas and the guide rod / recoil spring assy. It does little for the feed path, barrel and other parts that get load placed upon them during actual firing. Still, if the slight FRB issue is being caused by the slide being a bit too tight for its own good, then the work should have good benefit. I'm betting the chamber throat and feed path are still a bit tight as well, given what you've indicated so far. Time will tell.
If you can put ~100 FMJ rounds through without much issue, then try out JHP or JHP/FMJ mixed. If THAT then works fine as well, then it's a good bet the issue was simply overall stiffness that has nearly been cured. If you still have issues with certain rounds only, then you'll need to consider what it is about those rounds that the gun doesn't like ... such as, too great of length from case base to ogive shoulder against the lands, or the crimp sticks out a bit too much and grabs along the feed way, or something that's ammo specific. Remember that not all guns like all ammo, and some guns show a particular dislike of certain ammo. You might end up needing to simply change JHP (?) ammo to something a bit smoother, shorter, whatever.
That is a high amount of failures.
I'm into about 220 rounds on my new Kahr PM9 and have not experienced one failure, but I can feel a noticeable difference in the gun as it 'loosens up.' I cleaned it before I fired it, cleaned it at 126 rouns, and then cleaned it again this weekend after the second trip to the range. I've not had a failure yet, but I am still learing how to grip the little monster.
taseal, Take a look at the inside top of the slide (#6 on the lube diagram) and you should see a wear point. Best case is it will be smooth but mine was rough and gouged. Then look at the top of the barrel where the chamber drops to the barrel. That very top edge is what rubs on the slide (pushes the barrel down). It should be square, but not sharp when you rub you finger over it.
I smoothed out the slide and took the sharpness of the barrel top with a dremmel polishing tool making the single most improvement to the slide action smoothness.
Spray cleaners: It is the chlorine in brake cleaners that are bad on the poly body. Non-chlorinated brake cleaners are ok for that. However, stories out there about them damaging painted and laser sights. That cleaner is very potent stuff and I like it, but treat it with respect.
keep us posted on how things turn out with your p380..i was very interested in buying the p380 at one time,but bagan having second thoughts after reading similar problems from other Kahr p380 owners...i'm sure Kahr will make it right if you have to send it back in, but kind of disappointing,especially for the $$$ they charge for that thing..
Went back to the range and shot another 150 rounds. making it total of 200...
towards the end of 200, it was still acting up. there was a magazine towards the end (170th or so) where EVERY ROUND did not go off (light striker) i would rack it, push on the back of the slide to sit it in, and nothing. The only thing diff with that was, it was a long shot and i was concentrating on the trigger each time.
however, it did work great when I shot single handed, or when I stiffened up my wrist to prevent limp wristing.
I've been shooting guns for a while now and I know how to shoot a pistol, I've never had limp wristing problems since I started shooting with all sorts of pistols...
I just don't know anymore.... I'll clean it real well and take it out again, if it's giving me problems, I'll get a video of me shooting it at the range, and send the pistol in along with a cd of the video
so right now, I think the main problem is light primer strikes, possibly due to the slide sitting only 99%
I've used PMC, Blazer, and Lellier and Bellot with all same failing results.
eta: cleaned her up, feels very smooth now, and no matter how slowly I put the slide forward, it closes all the way without a problem. Next range session will decide this pistol's faith for me
If you're noticing the gun being seriously smoother and more reliable, and if really the only thing going on at this point is stiffness that keeps the slide from fully going forward into battery (by just a fraction of an inch), then you might well be nearing the transition point.
It might well benefit by racking the slide another couple hundred times to the point of those last few "flakes" of high metal getting shaved off. Worth a shot, as that won't even cost you ammo.
What I would do, if my P380 were acting like this at this point in its break-in: I'd take the most-reliable two magazines and ammo I had noticed so far, then continue shooting 5-6rds of reliable FMJ (only) in each magazine for the next few dozen magazines' worth (for the next ~80-100rds). Be sure to keep it clean and well-lubricated (IMO, every ~50-60 rds now). Keep in mind, too, that at this point you might well have only one or two brands/types of ammo that work pretty well in the gun, whereas all others are still stiff and cranky. Note specifically how the performance goes, with respect to smoothness, any jams, how and when the slide doesn't go into battery, on which round in the magazine that occurs, etc. Keep good notes. If you notice the statistics go toward zero and then good performance continue from then on, you're likely home free. If not, then you'll have several hundred more rounds of good statistics and details to hand to Kahr when you speak with their warranty/fix-it shop. The more details, the better.
Did you take down and clean the striker channel? I've read a couple light primer strikes where the channel had manufacturing gunk in it. It should not have any, but it has happened. Look at the thread "How To "Detail Strip" the Kahr's Upper!" One caution is to be extra careful when messing with the firing pin spring. It can put out your eye like a BB gun or achieve near earth orbit if you turn it loose. Some have devised a holding tool from a metal close hanger and it's covered somewhere there also.
I'm confused by your "however, it did work great when I shot single handed, or when I stiffened up my wrist to prevent limp wristing." Then the most failures came with the last rounds. The P380 has a definite snap unlike many pistols and you hand may be getting tired. I suggest taking a towel to fold into a hand rest and use it to eliminate possibilities if you have failures next trip.
The other thing is eliminating the mag as a problem. Is there a difference between them in failures? If so, only shoot the good one and track how the gun does with that.
I'm going to hold my toes and cross my breath until we hear your next report.
Both Mags are giving me problems
I did some more dry cycling today and I realized that the FTRB is happening when the magazine is loaded. without a round being chambered, it is very smooth. when it needs to chamber a round is where the slide is getting stuck 90% of the way....
I'm going ot try to make it to the range this weekend again but the ammo is 25-26 bux a box and online it's only like 13-15 bux... so I might order bulk soon and go out again
Are you using the slide lock method to chamber the first round? When it hangs at 90% where is the cartridge sitting? Can you see if the extractor has the cartridge rim in it's hook?
Are you shooting only FMJ rounds? Please don't shoot hollow points until the gun is functioning properly. 9mm FMJ should not be $25 for a box of 50. I haven't looked lately, but it was about $15 at Walmart weeks ago.
My brother in law has a Kahr, and it requires a firmer than usual grip to get the gun to cycle everytime. The gun, being as light as it is needs the additional weight of your hand with a firm grip to cycle properly. You may want to be conscious of your grip and see if it does indeed make a difference.
and yes, they are all FMJ rounds, I don't even own any HP ammo yet