1927A1 vs. M1 feeding

[OD#3]

I recently purchased my third Kahr "Thompson SMG" clone. My first was a "Commando" model. Having eventually persuaded myself that it was a silly range toy, I traded it for something I thought would be more "practical". I got bit by the urge some years later and ordered an M1 version. Again, I soon persuaded myself that it had no practical purpose, especially with that ridiculously long barrel, and I sold it. Bit by the bug yet again, I have recently taken delivery of my third--a 1927A1 deluxe version that came with a 50 round drum and 20 round stick magazine. I took it to the range for a very brief proving session yesterday.

 

First, the drum magazine was a bit disappointing. I wound it 9 "clicks", which proved to be too few. Evidently, not every "click" I heard was actually a "click", and it was probably wound too little. The rifle began to choke after about 10-15 rounds. I found that there was no more tension on the spring, and the rounds weren't being presented at all. Irritating, that. A brief internet search revealed that there is a difference between the "click" and the "clunk" sounds as one is winding. Evidently, I counted them both as "clicks", when I should have counted the louder of the two.

 

The stick magazine was better, though it suffered from a couple of feeding issues. What I don't understand, is why the feeding funnel is so different between the 1921A1 and the M1 versions. I also suffered terrible feeding jams with my first Commando model. The rounds would get jammed sideways often, and I was only able to get it to feed reliably by graduating the transition between the initial wide part of the funnel and the narrower part. Some rounds had been striking the wide portion and glancing almost sideways. My grinding that sharp change in angle to a more gradual transition put an end to the sideways feeding jams.

 

When I got my M1 version, I noted that the feeding funnel had no such change in angle--it was a straight funneled shot to the chamber, and I encountered no feeding issues of any kind. I chalked that up to my original commando model having been an early Kahr gun, and I figured that Kahr had tweaked the design some to make feeding more positive.

 

Imagine my disappointment to discover that my new 1927 A1 model suffers from the same affliction as my old Commando model. There is a marked change in angle of the feed funnel from very wide to narrow, and some rounds, when presented from the staggered lips of a stick magazine, evidently glance off the first angle and tilt the whole round sideways enough to hopelessly jam the bolt against a round that is wedged in the funnel. I suppose I'm going to have to do some grinding and/or stoning on this rifle's feed funnel as well, if I'm going to achieve reliability. But I hate to have to do that.

 

I've persuaded myself that a range toy with no "practical" use is still something worth having, so I'm not going to trade this one off. And I'm actually planning to SBR this one, which should take care of my other major objection. I'm still left with reliablity, however. I hate to start grinding/filing/stoning on this new rifle, but it appears that I'm going to have to--unless someone here has some other tricks or tips I should try first.

 

On another note, anyone know why the "third hand" is so much narrower than the slot it fits into? As it is, the "third hand" sometimes twists in the slot and binds itself up. I'm tempted to make one of my own that actually fits.

[58healeybn6]

I can't help you with the feed ramp, but I can tell you what I did with my 50 round drum to fix it. I had an original 1921/28 years ago and I knew that my original drum did not sound the same as the new one. I took it apart and found that the rivets that were used to hold on the instruction plate were too long where they were peened over. The "ears" on the winding mechanism which click when the key is turned were being lifted by the rivet heads and making a false clicking sound. If you very carefully gring the rivet heads down with a Dremel, you will find that you can eliminate the false clicks. There should be four clicks per revolution of the winding key. Just make sure that when you are grinding the heads, that you don't take off too much. Take off a little, try the key, and keep repeating until the sound is minimal. Good luck.

[OD#3]

Thanks for the advice about the rivets. I'll check them out and report back.

[deerslayer]

When you sbr it you can do the feed ramp right much easier from the front with the barrel off.