I made, 'First Class Shot' using a TSMG, Tommygun during Infantry training in the British Army during WW2, however I would not carry one in action, the reason was the American made ammunition. The British made a . 45 round but it was Revolver ammunition and unsuitable for use in a Tommygun.
We were taught the ins and outs of the Tommy gun, how it worked, taking it apart, cleaning, reassembly etc, but the first time to fire one was also a test of your use and scores. You started with a full magazine, the first 5 rounds were single shots aimed at a score target. From there you set it to automatic and walked between targets firing in bursts, then breaking into a run and running in ziz-zaz fashion through targets again firing in bursts.
During the initial firing at the score targets, the first two rounds fired, however the third time squeezing the trigger I heard a dull thump, cocked the gun and the round was ejected and I fired again, a dull thud again, this time I held my left hand over the chamber and caught the round as I ejected it as I was standing in a foot of snow and did not want to have to dig in the snow to retrieve it with bare hands. (darned cold as I was) I checked the base of the round as I though perhaps the tip of the firing pin had broken off being it was so cold at the time, as two dud rounds in a row would be unusual, (although I never had any dud rounds firing British ammunition in any weapon) but it had a beautiful deep dead center dip in it. I reentered it to the chamber and fired again but it was a dud. I finished the course and got a first class shot with it, as all the hits were counted. I found it a pleasant weapon to fire, easy to handle, well made, but sadly it was the ammunition I had no faith in.
In recent years over the internet checking the British Army in Burma during WW2 have read where soldiers were killed as their Tommyguns jammed, in training I never heard of any jamming difficulties and I wonder how it could happen, as with all weapons, if any difficulties occurred when firing you would be instructed how to deal with them if a gun jams or misfires there has to be a reason.
The British Bren gun an automatic use the same . 303 rimed rounds as the rifles so when loading the magazine one had to insert one round under the other, meaning the next rim under the previous inserted rim, otherwise it would jam, but being well trained that would be unusual to happen. When loading a Bren magazine, one would enter the following rounds by placing the round rim on the body of the round already in the magazine and pushing up under the rim and in. I was also a first class shot on the Bren.
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