58healeybn6

I have a 1927 Kahr made several years ago. I switched out the Kahr rear sight for an original Lyman sight. I kept the Kahr sight base and just switched out the ladder mechanism. As I recall, the only thing that I had to do was make a new spring plunger to hold the Lyman sight in the correct upright position. Hope this helps.

CJR, I would suggest that you get the PDF from Deerslayer, he has always been right on.

I looked in Tracy Hill’s “The Ultimate Thompson” book and there are drawings of the original Thompson parts, which includes the vertical front grip. The problem is however, some of the dimensions are missing; whether on purpose or not I don’t know. I purchased an after market grip from Sarco, which was fairly close and reconfigured it as close as possible to the drawing dimensions. I did have to drill the bolt hole at a bit of a different angle because the front grip on the Kahr Thompson is not at all like the originals. If you would like, I can trace my grip and send it to you. I also had to carefully widen the mounting slot but if you are a decent woodworker, it is not difficult to do.

You also want to make sure that your bolt and interior surfaces are smoothed out and lubed. I use a light coating of lithium grease and oil. Also, get rid of those d......d heavy springs. I have been using the EZ Pull springs for two years now with no problems. Personally, I think that they give the bolt, firing pin, and extractor a lot less abuse too. Less hammering. My humble opinion. I also reload too, so I load just heavy enough to cycle the bolt and get good accuracy. Less wear and tear.

I installed a 1928 butt stock and original metal on mine. There is not much end to end play, but more side play than I liked. I have a drill press and drilled and tapped two holes for 4-40 set screws about 1 1/2” apart in the slotted part of the butt stock metal I screwed them in so that I had minimal side play and lock tighted them in. Worked great.

I have not used the 100 round drum; the 50 adds enough weight. All the drums are finicky until you get the bugs worked out of them. They’re a bit of a pain in the ass to use. I have used mine a couple of times, but prefer a 20 round mag. My humble opinion.

If it indeed is a detachable type of stock from a 1928 and it is missing the mounting hardware, those are sometimes available on ebay, but more often on Gunbroker. Make sure that you buy from someone in the states; a lot of east european stuff out there. Make sure that it has the spring, button, and hardware with it.

I presume that the stock has a push button release at the rear of the wrist, making it for a 1921/1928 or 1928A1. If it has a crossbolt at the wrist, it would be for a 1928A1. If it does not have a crossbolt, it could be for a 1921 or 1928. Either way it should fit right onto the 1927A1 receiver. I did that with mine; fit with no problem.

The charging handle on the 1927A’s are entirely different from the actuator knob on a 1928. The 1927 is a separate piece that fits into the hole in the bolt that the firing pin slides through. It has to be separate to fit over the firing pin which is held in the bolt by retaining pins. The 1928 that your father carried has an actuator (with attached knob).which fits over the bolt. The 1928 fires from an open bolt and the 1927 fires from a closed bolt. Two entirely different systems. That is why our 1927s are loose and the 1928s are not. When a 1927 is disassembled, the knob is pulled up through the hole in the receiver. In a 1928, the actuator with knob is removed from the inside of the receiver. Your charging handle (knob) has to be somewhat loose to slide in. My bluing on my steel receiver is worn also.

Looks good. Now, put a thin coating of linseed oil on after the stain is good and dry. Rub the linseed oil in and let it dry for a week or so rubbing it in occasionally. Repeat this proceedure for several months until the oil doesn’t soak in. Let dry and rub out. The oil will eventually oxidize, giving the stock that nice aged reddish hue that you see on old military weapons or on the original Thompsons. I have an original Thompson detachable stock (no reinforcing bolt) on my 1927. It really looks good with the aged linseed oil finish. I have also replaced the hokey rear sight with an original Lyman 1928 sight, replaced the AO front vertical grip with a very close to original 1928 vertical front grip, modified the upper receiver to allow removal of the lower without any additional tool, and installed EZ-pull springs from Dan Block. Also modified my drum so that it runs smoothly. Shoot with no problems.

Sorry, since I reload I know by factory ammunition. You could probably look on the web and see if there is anything out there. Try Midway USA.

OK, I see what you mean now. I looked at my parts break down in my owner’s manual and I see that the pin is labeled “firing pin pilot”. I can’t think of any reason that it should peen either. I have no evidence of that on mine. However, as I said earlier, I run a reduced load through mine, so I would not have a heavy recoil anyway. I did some tests a year or so age and posted the results; I did some chronograph tests with factory ammo and the velocities were greater than a 1911 because of the increased barrel length. With the reduced load EZ-Pull springs, I wanted less recoil. That being said, I can’t see any reason for your peening unless, as you said, it’s firing out of battery, but even then, it shouldn’t have that effect. Maybe just crap steel. To answer your other question, no, they did not give any explanation. Probably don’t want to admit it.

I’m not sure I understand what you mean by the “firing pin pilot”? Do you mean the hole in the bolt that the firing pin goes through? If so, could the pin be slightly bent or perhaps a bit too long? The pierced primers would seem to indicate this plus the heavy firing pin spring would exacerbate this. How much of the pin protrudes from the bolt when the front part of the firing pin body is flush with the face of the bolt body? As you probably know, the inside face of the receiver acts as the stop for the forward motion of the firing pin. Regardless, if you send it back to AutoOrdnance with a list of your issues, they may fix them as well as the double tap. My first 1927 had a multi-fire issue and they fixed it.

I doubt very much if it’s weak springs. I have the EZ-pull springs on mine and it runs fine. I can pull the actuator back with one finger. Have not had any problem with that at all. For what it’s worth, I load my own 45 ACP, and I run a reduced load through my 1927. Accuracy is very good and recoil is light. All I need is enough recoil to retract the bolt all the way and to seat a new round. Of course, if you still have the warrantee in effect, you probably want to keep it stock. My personal opinion is that the very heavy forward slamming of the bolt against the receiver with the factory springs can’t be doing it any good.

If it is a new gun, call Auto-Ordnance and tell them your problems; especially that it double/triple tapped. They don’t like to hear that. They should give you a pre-paid number to return it. Some of their customer service guys are jerks and some are pretty decent. If the gun is used, all bets are off. I personally am not a fan of aluminum guns, but that’s just me. Good luck.

Whibble, Where are you located? I have one that I made a couple of years ago that I will let you borrow as long as you pick up the mailing cost and return it. I made it out of a 1" square piece of aluminum. It is bored to fit the o.d. of the rotor axle and fitted with a zerk fitting at right angle to the bored hole. This gives me a flat surface to use as a clamping surface. On the other side of the axle, I made an aluminum pin with an enlarged base to insert into the hole in the axle. It worked good. You will need a small grease gun available at any auto store foe a few bucks and a clamp that will span the two pieces. I am in Knoxville, Tennessee. I will post a photo if you want to see it. Let me know.

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.

I agree with Garlicrazy. I have had mine for a couple of years; put on a 1928 detachable stock, original Lyman rear sight and a correct vertical front grip. I have had a couple of issues so I also invested in a video from American Gunsmithing Institute on Thompsons which includes the 1927 disassembly. I do any repairs or mods myself; the more you know about the gun, the better you will be. Just be smart about what you can do and what you can't. Also, contact Dan Block for an EZ-pull spring kit; makes a world of difference. As has been said, Kahr's customer service is rude and all they will do is tell you to send it back if you have issues, but I'm sure that is driven by the lawyers. I think the quality is very good; they just need tweaking to make them great.

I got my EZ Pull springs from Dan Block. Great to do business with! I also believe that the EZ Pull springs are easier on the bolt and extractor due to the fact that they are not being slammed as hard when returning forward into battery as with the factory spring setup. I have not had any problems and the gun runs fine.

If Dan is back logged or if you decide that is not what you want, Sarco has a very close reproduction. I recently purchased one from them to replace the bad reproduction that I had previously purchased. Sarco's was very good. I had drawn one out on my CAD program from the dimensions given in the drawing shown inTracie Hill's book "The Ultimate Thompson Book". The fore grip I received from Sarco was right on, but had to be finished down to the final contours, sanded, stained and given several coats of raw linseed oil. Let the oil work for several months and it will turn the correct reddish color. Dan's will probably be less hassle if you are not a woodworker.

Paul, this is probably a non-answer. It depends on several things; condition, whether or not it has a detachable stock, which fore grip, box or not,etc. Are these new or used? If used, what is with them? Does the drum mag gun have a stick mag with it also? Bear in mind that although the drum is cool, it is a pain in the ass to use and most of them need some tweaking to make them work right. Also shooting with less than a full drum is difficult to do unless you are acquainted with its' idiosyncracies. Take a look at what is listed on Gunbroker to get an idea of price ranges. Once you get all the bugs out, they are a hoot. Good luck.

I recently replaced the sear block on my AO 1927 with no problem. I was having a couple of double taps with mine and the rear of the sear block looked very similar to yours. I am wondering if your firing pin is catching on the rear of the sear block where it rides over the safety. That would account for your having to pull the trigger halfway to reset the trigger. It would drop a bit when you pulled the trigger halfway and slide forward to engage the correct sear. When you replace your sear block, you will have to check the protrusion of your firing pin where it contacts the sear block. Mine was .100" below the breech block bottom surface, but yours may be different. If it is too long, it will hit the rear of the sear block and hang up. Fit the firing pin protrusion with the hammer in place to ensure that the firing pin does not get pushed up when you are measuring it. A vernier works well to give you the correct measurement. As a bit of added info, I ordered the video on Thompson submachine guns from American Gunsmithing Institute for about $45.00 which also shows the AO disassembly and reassembly. Good luck.

Just an update to my post. I have settled on a new reduced load for my 1927A1 with EZ-Pull springs; a 230 gr. jacketed slug over 5.6 gr. of Unique powder. The recoil is minimal, accuracy is excellent, and ejection is consistent with the bolt locking back after last shot. As I said in my previous post, my main objective is to reduce the impact on the rear of the receiver when the bolt recoils, especially with the EZ-Pull springs installed. There may be an additional benefit to having installed the EZ-Pull springs set in that there must be a reduced amount of impact of the bolt when it comes into battery position and also a lesser amount of impact of the firing pin on the rear or the sear block. I have had no problems with the extractor or sear/firing pin since I installed the new springs several months ago. I post this load for information only and accept no liability for it.

Bought a box of Winchester 230 gr. hardball ammo this weekend and decided to do some velocity tests in my 1927 with EZ-Pull Springs in it and compare them with my reloads. Ten rounds of factory ammo gave an average velocity of 936.0 fps with a high of 951.3 fps and a low of 907.0 fps. Ten rounds of my reloads with 6.0 gr. of Unique and a 230 gr. jacketed Remington bullet gave an average of 930.2 fps with a high of 975.2 fps and a low of 882.2 fps. Tried the same scenario with my Colt 1911 with the following results; factory average was 850.5 and same reloads resulted in an average of 817.5. My cases were a mixed bag of manufacturers, all trimmed to length. All were taper crimped. For information, Alliant powder recommended starting load for the .45ACP is 5.85 gr. of Unique.

Has anyone done any chronograph testing with a Kahr 1927A1 with factory ammo? I recently installed the EZ-pull springs with excellent results. Since I load my own ammo, I've decided to load a bit lighter to reduce the breechblock pounding on the EZ-pull buffer. Alliant gives a maximum load with Unique powder of 6.5 grains for a muzzle velocity of 840 fps from a 5" barrel. I don't know what that equates to from a 16" barrel. I have settled on a load of 6.0 grains of Unique which gives me an average velocity of from about 840 to 940 fps from my 16" barrel. I would like to know if anyone has chronographed factory 230 gr. hardball ammo from their Thompson.