T40 Failing to lock up

[Kahrdriver64]

Guys, I ran my first IDPA match last night with my T40 and had several occurrences of failure to feed. The failure really ended up being the slide not going back into battery after firing leaving the round about 1/2" out of the chamber. Needless to say a real PITA.
This pistol has around 350 rounds through it. It was clean and had been lubed with Gun Butter on all the sliding parts and CLP on the trigger pivot. I have done the so called "Kahr action job" to it already. The one thing I notice is possible galling between the barrel and the slide both in the front 2-3 inches of the barrel and on the chamber faces a little, too. I had not lubricated the outside of the barrel, so maybe .....

Any ideas would be appreciated. I really want this to be my edc and IDPA SSP gun.

[Barth]

Guys, I ran my first IDPA match last night with my T40 and had several occurrences of failure to feed. The failure really ended up being the slide not going back into battery after firing leaving the round about 1/2" out of the chamber. Needless to say a real PITA.
This pistol has around 350 rounds through it. It was clean and had been lubed with Gun Butter on all the sliding parts and CLP on the trigger pivot. I have done the so called "Kahr action job" to it already. The one thing I notice is possible galling between the barrel and the slide both in the front 2-3 inches of the barrel and on the chamber faces a little, too. I had not lubricated the outside of the barrel, so maybe .....

Any ideas would be appreciated. I really want this to be my edc and IDPA SSP gun.

You didn't mention if the gun was purchased NIB or picked up used?
Generally when one of my autos starts to fail to return to battery it's a weak recoil spring.

[jocko]

I am assuming these are not with reloads either. U might check to see if the rounds could be OAL to long. But what Barth stated would be the first thing I would try. change the recoil springs. u just never know..

[wyntrout]

The barrel should be lubricated there because of the contact during operation. you might check the extractor for proper clearance and operation... case rims sliding under the claw and being held there during chambering and firing. My P40 had clearance problems with the rims and I removed a bit of metal from the affected areas on the claw and the sides of the breechface. My cartridges were getting about halfway into the chamber... at about a 45° angle. I don't know if this is your problem, though. It might be that the galling is impeding lockup and you need to sand, file, or stone down and polish those areas of buildup.

Wynn:)

[Kahrdriver64]

Thanks, I did buy it used off GB a few years back but condition was near new. I'm betting the original owner bought it and had issues right out of the box. It had ejector issues that I have worked out.

Looking at the Kahr Lube Chart sticky I can see a couple of key areas on the barrell and slide that I am not lubricating. This is my first foray into an all SS Kahr and I guess lubrication is much more important compared to the steel frame K40's.

As an aside, for those interested in IDPA with a "T". My impression regarding speed,accuracy, and capacity are all positive. The lack of 11 rnds just calls for an additional reload on longer stages. The inherent accuracy more than makes up for it IMHO.

[Kahrdriver64]

The barrel should be lubricated there because of the contact during operation. you might check the extractor for proper clearance and operation... case rims sliding under the claw and being held there during chambering and firing. My P40 had clearance problems with the rims and I removed a bit of metal from the affected areas on the claw and the sides of the breechface. My cartridges were getting about halfway into the chamber... at about a 45° angle. I don't know if this is your problem, though. It might be that the galling is impeding lockup and you need to sand, file, or stone down and polish those areas of buildup.

Wynn:)
Galling on the underside of the barrel when it drops out of battery is an area that I'm thinking, too. It was late last night so I haven't inspected and cleaned yet. The barrel and oblong hole (where the barrel bushing would be) feels like the source of drag to me.

I guess these SS guns need help shooting in. My old steel frame K's lapped themselves in pretty easy.

Thanks

[jocko]

if it was my K40. I wold polish the hell out of the barrel on the outside and in thebarrel lub and the feed ramp, even thogh it looks good u can do better. Then I would get some 6500+ grit paper or even a higher number and polish the inside of the slide rails where it slides on the rails of the frame. I would also polsh the rails on the frame also. Ur jsut smoothing, ot taking off any real metal here. Then I would follow to a T the kahr lube chart. U can polish the extractor claw right on thegun even with some fine paper. It only takes a little burr in this set up to mess things up. In no way are u harming anything on this gun buy doing the above either. a dremel and a cotton swab can speed thing sup and with some flitz a sthe polish, ur again not gonna harm nuttin..

[Kahrdriver64]

Thanks Jocko. I ended up polishing the barrel od to near mirror and repolishing the feed ramp . I switched from gun butter to triflow and lapped the rails some more. I did find two tiny burrs in the slide rails that I dressed.

But after all that, I ended by grinding a full coil off the extractor spring. The back of the casing was hanging up and not getting up the boltface. Now I can ride the slide forward and the round will snap into the chamber.

The gun ran an idpa classifier Saturday with no issues.