K40 troubleshooting, fixed, runs great now thanks

[b4uqzme]

[QUOTE=Barth;280761]
I'm a big fan of the all stainless Kahr autos.[/QUOTE

Ditto ^^^^^

... Sorry you had to trade pistols but I'm glad you found a solution.

[AFCop]

I'm happy with the trade as it shoots much more reliably and I don't think the sticky trigger on the old one would have smoothed out with age.
I also wanted to go stainless because I want to take a stone to the sharp edges on the beaver tail that are cutting into my dominant thumb. Anyone else have that problem? It drew blood after 50 rounds.

[Barth]

I'm happy with the trade as it shoots much more reliably and I don't think the sticky trigger on the old one would have smoothed out with age.
I also wanted to go stainless because I want to take a stone to the sharp edges on the beaver tail that are cutting into my dominant thumb. Anyone else have that problem? It drew blood after 50 rounds.

My MK40 Elite I believe came with the melted treatment from the factory.
The Kahr Elite treatment I think has a smoothed and polished exterior,
beveled magazine well and polished feed ramp.
The trigger feels like the internals may have been polished as well.
It's like the gun went to the Kahr custom shop after it left the factory.
I asked my gunsmith what else could be done to the gun? And he said nothing...

Got my Elite complete with the factory NS.
I highly recommend those options.

[b4uqzme]

I also wanted to go stainless because I want to take a stone to the sharp edges on the beaver tail that are cutting into my dominant thumb. Anyone else have that problem? It drew blood after 50 rounds.

Hmmm. I'm not sure I'm clear on what you mean. I remember the slide lever rubbing my RH thumb at first and I resolved that by adjusting my grip. When I added the thicker wood grips that also helped as the lever didn't stick out as much. I believe many also dehorn the slide lever and that's a good idea.

Everything in the backstrap/bearvertail area is really smooth. Are you talking about the bottom edge of the slide? Those are the only sharp surfaces I can see back there. If so, I think the best cure for "slide bite" is to shore up your grip.

Not sure if that helped but....

[AFCop]

Hmmm. I'm not sure I'm clear on what you mean. I remember the slide lever rubbing my RH thumb at first and I resolved that by adjusting my grip. When I added the thicker wood grips that also helped as the lever didn't stick out as much. I believe many also dehorn the slide lever and that's a good idea.

Everything in the backstrap/bearvertail area is really smooth. Are you talking about the bottom edge of the slide? Those are the only sharp surfaces I can see back there. If so, I think the best cure for "slide bite" is to shore up your grip.

Not sure if that helped but....

I would post a picture but I apparently need to have 30 posts under my belt first. There are pictures on the site showing the area I am talking about but I will try to describe it better.

The top of the grip where a beaver tail would be if this were a 1911. I grip high, pressing the web of my thumb into this area. On the all steel K40 there is a sharp angled edge where the back of the grip transitions to the side of the grip. On my first black carbon K40 this edge was sharp and cut into my thumb. This newer stainless guns has a "slightly" more rounded edge.

I would like to round it off a little more. Wondering if a stone is the best way to do this. Not sure if sandpaper will do much to stainless.

[b4uqzme]

I think I got it. I never even noticed that area before as it never presented a problem. Sure - I think you could soften those edges a little but I'd start with the sandpaper first and maybe some emery cloth? It really shouldn't take much. You probably want to protect the integrity of those curves so a stone with a straight edge might be a problem. But I think I see what you mean. I think mine is just softened with 15 years of wear

[AFCop]

Yes, that is the culprit, that edge rests right on my thumb knuckle.

I was going to borrow a round machinists stone, if you say sandpaper will work I will start with that. I assumed the stainless was too hard to sand.

Thanks for the input.

[b4uqzme]

Give the sandpaper a try. You can always upgrade to the stone. Whatever you think will take the least material is what I'd start with.

Some here who've done "melt" jobs may have some good input.

[FLBri]

Sandpaper will be more controllable on an irregular shape like that. Depending on the amount you want to remove, I would start with 220 and progress to 400 with one or to steps between. Try to keep your removal to the very edges, because if/when you hit the back flatter area you will change the sheen.

I would put some masking tape, or electricians tape on the flats that you don't want to change. Finish the edges off with a gray scotch brite pad and you should be pretty happy with the result.

[AFCop]

Sandpaper will be more controllable on an irregular shape like that. Depending on the amount you want to remove, I would start with 220 and progress to 400 with one or to steps between. Try to keep your removal to the very edges, because if/when you hit the back flatter area you will change the sheen.

I would put some masking tape, or electricians tape on the flats that you don't want to change. Finish the edges off with a gray scotch brite pad and you should be pretty happy with the result.

Great advice, Thank you.

[AFCop]

The stainless K40 performance has improved. I have been tuning and polishing parts in an attempt to resolve a coulple of issues.

During the last 50 round test fire:

One jam, the round became wedged between the feed ramp and the breech face with the rear of the case tilted upward.

(I have polished the feed ramp)

Three or four return to battery without stripping a round.

(Removed the magazine catch and polished the bevel, sanded and polished the magazine followers so they pass the mag catch smooth when a disassembled mag is inserted in the mag well.)

Three or four premature slide lock.

(Sanded and polished the slide stop lever so rounds rising in the magazine are less likely to bump it and engage the lock.)

New springs are on order. I will let you know how the next fifty rounds goes. I wont give up on this Kahr as I love it so. I am commited to seeing it through until it is dependable. Thank you all for your advice and input.

[AFCop]

Shot another 50 rounds after sanding and polishing feed ramp, mag followers and internal slide stop lever. Experienced less malfunctions. I am starting to think the gun doesnt like the shape of the bullet on my duty ammo.

Had one slide lock with rounds in the magazine.

Two rounds wedged between feed ramp and breech face.

One round jammed between the top of the barrel and the breech face.

One incident of going full into battery without stripping a round.
(Not sure what is causing this or how to fix it)

One fail to lock back on empty magazine. (probably because of my slide stop modification) Will attempt to post pictures from photobucket.

I will try to find some ammo with a bullet that is not as blunt as this Federal 180 JHP and see how it performs. Sure would like to shoot this round as I have better access to it.

This is the ammo I am breaking the pistol in with and the ammo I would like to use for every day carry.

[AFCop]

It running good now.

Replaced the slide stop with a free factory provided new slide stop.

Replaced the recoil spring and the magazine springs.

No jams, no premature slide lock, no failure to strip a round.

All of the problems were solved with new springs. The new magazine springs were about three times as long as the old (set) mag springs. I broke a sweat trying to cram all that coiled steel into those little mags.

I think the weak mag springs were allowing the rounds inside the mag to ride forward and engage the slide lock lever on thier way up.

Thanks for all your help.

So all is well, I have been meaning to ask you other K40 owners. Does your slide stop hole have a notch cut in the top near the slide stop spring inside the frame like this?