
27 Frames
#21
Posted 28 March 2004 - 01:14 PM
Thanks!
#22
Posted 28 March 2004 - 01:21 PM
#23
Posted 28 March 2004 - 02:14 PM
Send that puppy to PK for his most excellent sight riviting treatment.
Never a problem again!
Zamm
#24
Posted 28 March 2004 - 09:18 PM
Little off the subject, I know Dave has been working on spring & buffer modifications, for easier pulling of the bolt. I think that is a major need to make the Kahr transformation complete. No pressure intended, but I wonder if anyone has heard anymore about that project.
#25
Posted 29 March 2004 - 10:58 AM
First, the desire to use the ’28 SMG detachable stock has been #1 on the semi auto owners wish list since these guns were introduced; and rightly so. Attempts to accomplish this have ranged from the ungainly NAC adapter (offered soon after the guns) to some very nicely done alterations that come very close to the real ’28 SMG frame (I did my first one in ’76). While a nice conversion can actually be accomplished for less money, there is definitely a market for an “off the shelf” product, and such would be welcomed.
The second change being discussed is not so simple. It should be noted that the infamous .10” that separates the FA and SA guns was taken from the square, rearward part of the receiver and bolt, not the frame. The front part of the receiver that accepts the round “stem” of the bolt remained unchanged. The SA frame is basically the same as the FA part (with small modifications). This allowed the use of modified surplus FA parts in the early design (did you know the first SA sears were made by cutting a notch into FA sear levers?). The intent of the .10” change was to preclude a FA bolt being used in the SA receiver.
Because the top plane of the frame is the lower surface upon which the square part of the bolt rides, the relationship of the fire control components contained in the frame to this surface is important. As the receiver was shortened, the fire control components and frame (in effect) rose of necessity, taking with them the magazine catch. This necessitated the use of modified box magazines or a modification of the mag catch because the top of the box magazine stops against the receiver. It had no effect on drums as the drum slots that position the feed lips in relation to the bolt stem are cut into the receiver and were not moved. The lateral clearance slots in the frame for the drum mag catch protrusions were lowered, however.
Some thoughts on lowering the frame to compensate for the magazine catch position: The portion of the frame that contains the fire control parts can not be changed, as these parts would not then be able to interface with the sear, or bolt. The only part that could be functionally lowered would be the magazine catch. The shape of the magazine catch is such that it shadows the trigger guard cutout on the left side. If the catch is lowered on it’s own, it will intrude into the trigger guard .10”. If the trigger guard cut out is lowered in order to compensate, the top .10” of the trigger will be buried in the frame. Neither option would seem to offer much in the way of improved esthetics, and having .10” less trigger to pull seems awkward too.
All this assumes that a stock SMG magazine catch is to be used on the new frame, without modification. I am not sure what the answer to this problem may be, if there is one. It would appear to me that some compromise is still needed, and I am not convinced that there is anything better than simply lowering the engaging pin on the magazine catch, as has been done for years.
The above is simply the ramblings of an old man on a spring day. I wish Damon all success.
#26
Posted 29 March 2004 - 01:09 PM
#27
Posted 29 March 2004 - 02:55 PM

#28
Posted 29 March 2004 - 06:17 PM
DO add the rocker piviot hole, wether it's marked lock/unlock, Automatic/Semi Automatic, Full Auto/Single, or best yet offer all three variations with the parts needed to make it work so we can either put the %#^&*@! third hand in a drawer as a future colectable or put the third hand in its propper place (the trash can).
Can we pre order yet?
BB
Bisley45@hotmail.com
#29
Posted 29 March 2004 - 06:46 PM
#30
Posted 31 March 2004 - 10:01 AM
how could you move everything .1000" of an inch, if you moved all the holes down the sear and disconector would have to be built up to engage the bolt. I could see moving the magazine catch down .1000" so an unmodified GI catch could be used but that would block off some of the space in the trigger guard. I find that a bad idea, so would anyone else with normal or large fingers. I'm not mutton handed but I like space around the trigger so I can wear gloves and not get my fingers bound or pinched.
BB
Bisley45@hotmail.com
#31
Posted 31 March 2004 - 11:45 AM
Edited by LIONHART, 31 March 2004 - 11:56 AM.
#32
Posted 31 March 2004 - 12:08 PM
#33
Posted 31 March 2004 - 12:40 PM
"6) What do I mean by "Hang Lower"? Simple. When WH designed the Semi-Auto Thomspon, the Receivers were reduced in height by one-tenth inch. They did this to eliminate persons from installing FA Bolts, ect. By doing this, the Trigger Housings (Frames) mounts one-tenth higher on the SA Receivers. This has caused Drum fitting problems, and Magazines must be modified in order to compensate for the height reduction. NOW, Damons' Frames will be made to hang one-tenth inch lower. This will solve the problems of fitting Drums/Magazines, plus creating that proper Thompson SMG look that were all fond of. The original one-tenth height reduction on the SA Receivers are quite noticable. If one has a '27 next to an original '21/28 one could easily tell a big difference. With these new Frames, the original look of the TSMG Receiver/Frame for YOUR '27 will be intact. Even using a modified '28 Frame one still has to modify Magazines, or modify the Magazine Catch since there still is a height problem."
I'm not following you. I know the recever is .1000" shorter, how are you going to make that up with a trigger frame without moving the pin holes. I don't get how you can move the whole thing as you have to keep the sear in contact with the bolt. If you move the mag catch location down .1000" you can use an unmodifed magazine catch but if you move the rest of the holes down you have a .1000" gap between the leg of the firing pin and the sear and the disconector. Maybe you need to draw me a picture. How can you make the outside hang lower and not screw up the interworking geometry /or/ have the trigger stuck .1000" higher in it's opening.
I loved the idea until the .1000" was mentioned and using the unmodifed mag catch. Then I got LOST and BEFUDDLED.
BB
Bisley45@hotmail.com
#34
Posted 31 March 2004 - 01:16 PM

Edited by LIONHART, 31 March 2004 - 01:17 PM.
#35
Posted 31 March 2004 - 01:22 PM
BB
#36
Posted 01 April 2004 - 05:27 PM
Scott
#37
Posted 01 April 2004 - 06:37 PM
#38
Posted 02 April 2004 - 07:46 AM
When a detachable stock is detached from a standard 16 1/2" barrel 27A1 does the overall firearm length become less than 26"?
If so, I think I could own the gun but I would have to register the gun as a pistol according to my local rules.
Thanks to those who know.
The straight-forward frame swap does seem like a simple, clean way to provide a more portable and realistic product.
#39
Posted 02 April 2004 - 09:20 AM
BB
#40
Posted 02 April 2004 - 10:52 AM