walleyealx Posted October 1 Report Share Posted October 1 Wanted to give my M1A1 a good cleaning. Never taken apart the lower. I was watching a video of a gentleman stripping and reassembling the lower, and he doesn't zoom in much. I thought I had it together correctly, but I'm having an issue. It cycles and and seemingly functions fine on auto, but when I go to semi the trigger won't reset and I have to pry it forwards. I took a couple of pictures of the lower both with and without the "rocker" in the orientation where I think it should be in. It could be something else, but that's my suspicion. Any other observations or things to try? Link to comment Share on other sites More sharing options...
Bridgeport28A1 Posted October 1 Report Share Posted October 1 (edited) http://www.nfatoys.com/tsmg/web/m1assy.htm Your rocker appears to be in the correct orientation. Did you take the springs out of their respective parts when you were giving it a good cleaning? Edited October 1 by Bridgeport28A1 Link to comment Share on other sites More sharing options...
deerslayer Posted October 1 Report Share Posted October 1 Maybe take it back apart. See if you have any little "burs" of metal on the edges that bear against each other. Make sure all springs not kinked. Also look to see if the grip screw protrudes out into the area. Link to comment Share on other sites More sharing options...
deerslayer Posted October 1 Report Share Posted October 1 Push the rocker forward by hand while its apart and your fully squeezing the trigger. You can see if the trigger resets properly when you release. 1 Link to comment Share on other sites More sharing options...
ppgcowboy Posted October 1 Report Share Posted October 1 You should get the the AGI video on the Thompson smg. There is a lot of good nuggets in it. Link to comment Share on other sites More sharing options...
walleyealx Posted October 2 Author Report Share Posted October 2 12 hours ago, Bridgeport28A1 said: http://www.nfatoys.com/tsmg/web/m1assy.htm Your rocker appears to be in the correct orientation. Did you take the springs out of their respective parts when you were giving it a good cleaning? I attached a picture of the springs that I replaced. Maybe one of them is incorrect or too strong? 11 hours ago, deerslayer said: Push the rocker forward by hand while its apart and your fully squeezing the trigger. You can see if the trigger resets properly when you release. The rocker is there so tight that I can’t push it to do anything. It’s pushing against metal, whether or not the trigger is pulled. Link to comment Share on other sites More sharing options...
walleyealx Posted October 2 Author Report Share Posted October 2 (edited) . Edited October 11 by walleyealx Removed video Link to comment Share on other sites More sharing options...
walleyealx Posted October 2 Author Report Share Posted October 2 (edited) . Edited October 11 by walleyealx 1 Link to comment Share on other sites More sharing options...
walleyealx Posted October 2 Author Report Share Posted October 2 Alright... Another update. After I did the above videos I put the old springs back in and everything worked fine. I ended up deducing that the "disconnector spring" that Apex sent me was way too strong and didn't let the rocker move at all. Side note: Just to confirm... You can't turn the selector to Semi unless the bolt is locked back (I.e. in the firing position), correct? 1 Link to comment Share on other sites More sharing options...
Chip Posted October 2 Report Share Posted October 2 Correct, the bolt needs to be cocked back before moving the selector or safety. 1 Link to comment Share on other sites More sharing options...
villafuego Posted October 2 Report Share Posted October 2 Eventually you may want to think about replacing that sear ....... the engagement surface of yours looks a little rough 1 Link to comment Share on other sites More sharing options...
tommydummy4 Posted October 2 Report Share Posted October 2 On 10/1/2025 at 6:11 AM, walleyealx said: Wanted to give my M1A1 a good cleaning. Never taken apart the lower. I was watching a video of a gentleman stripping and reassembling the lower, and he doesn't zoom in much. I thought I had it together correctly, but I'm having an issue. It cycles and and seemingly functions fine on auto, but when I go to semi the trigger won't reset and I have to pry it forwards. I took a couple of pictures of the lower both with and without the "rocker" in the orientation where I think it should be in. It could be something else, but that's my suspicion. Any other observations or things to try? In the pics, the rocker seems off. it should sit flat with the detent pin locked in; try removing it, cleaning the slot, and reseating per the manual. Also, dry-cycle the hammer and trigger a few times to spot any binding. Link to comment Share on other sites More sharing options...
p51 Posted October 2 Report Share Posted October 2 I love a happy ending! 😁 Great thread, everything was well communicated and explained. Link to comment Share on other sites More sharing options...
TD. Posted October 3 Report Share Posted October 3 walleyealx, I am glad you got your M1A1 back to running condition. I know many new (and old) Thompson owners want to replace springs and things when their Thompson gun is running fine. My thoughts on this are different. Since a Thompson submachine gun today is nothing more than a plaything used to shoot holes in paper target or destroy pop cans, I believe in leaving well enough alone until a problem arises. Most owners do not shoot their Thompson guns enough each year to even warrant taking the frame apart, much less changing out parts that are working fine. That said, I do recommend one parts package to new and old Thompson owners. Board member Phil Askew sells NOS (new old stock) parts. He has all the NOS frame springs in a nice package for a very reasonable price. I believe every Thompson owner should have one of Phil's NOS spring kits in their collection should the need ever arise to change out springs. I have never needed my extra springs, but I am glad I have them. 1 1 Link to comment Share on other sites More sharing options...
p51 Posted October 3 Report Share Posted October 3 3 hours ago, TD. said: I do recommend one parts package to new and old Thompson owners. Board member Phil Askew sells NOS (new old stock) parts. He has all the NOS frame springs in a nice package for a very reasonable price. I believe every Thompson owner should have one of Phil's NOS spring kits in their collection should the need ever arise to change out springs. I have never needed my extra springs, but I am glad I have them. And how would he be contacted? I tried looking him up... Link to comment Share on other sites More sharing options...
Chip Posted October 3 Report Share Posted October 3 https://www.apexgunparts.com/ 1 Link to comment Share on other sites More sharing options...
TD. Posted October 3 Report Share Posted October 3 Long time Board member Phil Askew can be reached at: philfordparts@yahoo.com APEX gun parts is a great company but for NOS parts, I always turn to Phil. 1 1 Link to comment Share on other sites More sharing options...
Rabbit57 Posted October 6 Report Share Posted October 6 I too have bought parts from Phil, he is easy to deal with. Another source for NOS Thompson parts is Richard Garcia of Tommy Gun Collectibles. He is still around and he has helped me a lot with my Thompson obsession. He can be reached at 416-937-1132. Good luck Mark Link to comment Share on other sites More sharing options...
walleyealx Posted October 11 Author Report Share Posted October 11 Thanks all. To TD: The real reason I took it apart is that I can't quite get either of the drums that Dan Block modified for me to work right. 😅 They work fine in his gun, but don't want to shoot in auto for me for the first 10-20 rounds. (See attached video of me trying to dump a drum). I figured it might be a weak spring somewhere. Still having the issue, but it works fine with sticks so it's not a huge deal. IMG_9406.mp4 Link to comment Share on other sites More sharing options...
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