Kahr Magazine Release
Posted 08 January 2006 - 12:10 PM
Posted 08 January 2006 - 02:11 PM
|I understand the semi automatic Thompsons won't accept original G.I. stick magazines. How do I modify the magazine catch to accept G.I. 20 and 30 round sticks?|
The magazine catch must be modified by lowering the lip that engages the magazine .100" while maintaining the original contours and shape. This is commonly achieved with a Dremel tool or files. After you have removed the safety, move the pivot plate so the ends of the pins are flush with the side of the trigger frame. Pivot the magazine catch out far enough to clear the magazine engaging protrusion from the hole in the trigger guard. Push on the end of the pivot pin part of the mag catch on the far side while pulling the catch out of the hole. Once the magazine engaging protrusion has cleared the side of the trigger guard, carefully allow the catch to rotate and unwind the spring. Remove the catch from the trigger housing . (Assemble in reverse.)
When reshaping the magazine catch, you must duplicate all the contours and angles when lowering the engaging surface. Removing .100" will allow use of unmodified GI magazines. Be careful not to remove too much metal. You may have to refit and test several times to acheive the optimal shape.
Posted 09 January 2006 - 01:40 PM
Here's the post in it's entirety, taken from my post at the WW2 Forum...
"Well, since this thread is now a sticky, I thought I’d post a few pics of the mag catch mod for you fellers out there who have yet to do it, kind of a before and after comparison. I used a Dremel tool with a cut-off wheel to re-shape the locking stud approximately 0.10” shorter than the factory SA one. You can buy these babies pre-shaped for about 40 bucks , or save a dollar or two and do it yourself. I bought the Dremel tool for 18 bucks, the cut-off wheels for 4 bucks, and the mandrel for 3 (all from Wallyworld)…so, I’ve got 25 bucks in it, plus a tool I can reuse over and over . Just take your time, and re-fit it every so often to check and test it.
Here’s a couple of shots of the factory catch. Note the top of the locking stud lip (in front of the groove) is level with the top of the locking stud…
Now here’s the catch after modification. Note the locking stud lip is about 0.10” lower than the top of the locking stud. Just be sure to maintain the same contours of the lip, notch and roundness of the stud. You can touch it up with some cold blueing if it floats yer boat for esthetic reasons.
Now, I can snap those USGI full-auto mags in all day long with ease! The fit of the mags after this mod doesn’t seem to be as sloppy as the altered SA mags, either; when I finally get my E-Z Pull spring set in, I’ll take her to the range and try it out, and give you a AAR.
My thanks goes out to all the guys who gave me the skinny on this mod, and offered their advice!
(PS…Later this week or so I’m gonna bfa my Tommy, and I’ll post a step-by-step photo log of it too for all you guys who are interested....)."
I hope this comes through!
I agree with Philohio on the part of fitting and re-fitting the catch after each bout with the Dremel tool...I must have taken my gun apart 6 or 7 times, checking for magazine lock-in...I had to wallow out a couple of my Crosby mag holes just a tad to get them to click...the Seymours worked fine...
And yeah...I got my info from the FAQ section ...and these links will help, too...
mag catch mod
mag catch mod 2
Posted 09 January 2006 - 03:24 PM