View Full Version : Thompson SMG Magazines

October 2, 2001, 09:32 PM
I am curious, do all Thompson SMG (semi- and full-auto) use the same magazines? I am in the process of buying a few to have a reason to eventually have to buy a full-auto version. But I came across a few ads that offered magazines for different Thompson models. Now I am wondering if different models used different mags? Can anyone tell me?


October 3, 2001, 09:20 AM
To use the drum magazines (50/L or 100/C), you need to have a receiver that will accept them (the 1921, 1928, and most of the modern commercial semi-auto reproductions). If you have an M1 or M1A1, these will only accept the "stick" magazines, which came in 18, 20, and 30 round versions. This is because the drum mags slide into the receiver from the side, but the stick mags slide up the front of the grip housing from the bottom. If a gun will accept a drum, though, it will also accept a stick mag.

October 3, 2001, 10:50 AM

Thanks for the info. My intent is to find a military model, preferably from WWII, so I think I will be looking for one which only takes the stick mags. My interest is military weapons primarily, but, if offered a nice civilian model at a reasonable price (i.e., one I can afford!), I would probably buy it.

October 3, 2001, 04:52 PM
There are are 2 different type of stick mags for the thompson....full-auto has a round hole for the mag catch...to use them in a semi-auto gun, you have to make the hole a oval...i love my thompson 1928A1.


October 3, 2001, 09:36 PM

Mine has the round hole and was made by the Seynour Products Co, Seymour Conn.

Johnny Guest
October 12, 2001, 04:27 PM
Good plan, Frosty.

If you intend to get a full auto, then don't bother with any TSMG box mag with an oval mag latch hole in it. It has been modified for use in the semi-only pieces, and may or may not work in a full suto gun. Also, people feel that those for the semi-only guns command higher prices than the others.

Generally, the 1928 (and earlier 1921) guns bring a higher price than the M1 and M1A1 WW-II guns. HOWEVER--If you're lucky enough to locate an affordable 1928 or 1928-A1 gun, these were used diring WW-II as well--just, normally, with the horizontal foreend. But the British forces, particularly, also used some with the vertical foreend. As previously mentioned, the 1928-series would also accept the 50-round drums.

If your main interest is the TSMG as used by the military, you can pretty well forget the 100-round drum. I don't think these were ever used by the U.S. forces.

Interestingly, the FIRST military use of the TSMG was the 1921 model, used by the Irish. One may debate the legitimacy of the Irish Rebel forces as a proper army, but, after independence, many of their guns went to the Republic of Ireland military stores. I believe they may have had some 100-round drums, which, BTW, were never intended for the 1928 models.

(Those better informed--Please forgive any misuse of terms concerning Ireland and her properly-constituted military forces. I an NOT talking about any terroristic organizations in Ireland.)

Both 20 and 30-round mags were used by US military in WW-II. Not sure when the 30-round came into use.

Good luck on your search for a full-auto.


October 12, 2001, 05:55 PM

Thanks for the info. My main interest is in a military model such as those used in WWII. I am a minor collector of military weapons and am especially interested in WWII memorabilia. Therefore my interest is in the M1/M1A1 models.

However, if I were to find a nice 1921 or 1928 in my price range, I would probably get it. Knowing the in's and out's of the various models and magazines ceertainly helps.

October 13, 2001, 07:56 PM
What is your price range? I have 3 thompsons....I love these guns.. even the semi ones....fun to shoot.....very good gun for what was made for...after WWI the army needed a weapon for "clearing the trenches"..... the thompson is very good at that....it gives the strong .45 acp more range.....stick mags are best in any gun.....see ya

Chris :D

James K
October 13, 2001, 09:31 PM
The information about the stick magazines is partly true. At first, Auto-Ordnance made semi-auto Thompsons that used the normal SMG stick and drum magazines. Then they changed the design in the magazine area and went to new stick mags and a new drum that holds 40 rounds; neither will fit the older guns or the original TSMG. Now, the new drums and sticks are 10 round and the rest is for show. The new guns will not accept original SMG stick mags without modification and will not accept original SMG drum mags at all - trying to make them fit will destroy them.

Original 50 round drums were going for around $400+, 100 round drums for well over $1000. So I don't think you want to get out the grinder to try and make these work in your semi-auto.


October 14, 2001, 10:00 AM
Unfortunately I have just picked up a nice, older S&W M12 and have my eyes open for an M-1 Carbine so the Thompson will have to wait. I have already told my wife that part of my 401K is fenced for this.

Jim Keenan,

Thanks for the info and the differences between the old and new models. I had a chance to purchase a new model but passed because I really want an older version. Unless my financial situation changes radically, I will pass on the drums. However, if I DO win the lottery, all bets are off.