I have some questions about the real figures for the cyclic ROF from the Sten MKII and the Thompson M1A1.  In the case of the Sten, some sources suggest it fires at 650 RPM, while others (most notably the small arms museum at Aberdeen) suggest 450 rounds per minute.  With the Thompson, most sources say it fires at 700 RPM, while Aberdeen again says 450 RPM.  I'm curious as to what the real figures are and why there is such a disagreement amongst sources.  Does anybody know which sources I should pay attention to ?  

Quoted: I have some questions about the real figures for the cyclic ROF from the Sten MKII and the Thompson M1A1.  In the case of the Sten, some sources suggest it fires at 650 RPM, while others (most notably the small arms museum at Aberdeen) suggest 450 rounds per minute.  With the Thompson, most sources say it fires at 700 RPM, while Aberdeen again says 450 RPM.  I'm curious as to what the real figures are and why there is such a disagreement amongst sources.  Does anybody know which sources I should pay attention to ?

Try "Janes" book on guns, the Sten fires 500-550, same with the M1A1 thompson, the thompson could fire faster about 50 rounds. 450 can be a reasonable RPM, both of mine shoot about that rate, the thompson seems to be slightly faster. The 1921/28 overstamp shoots in the 600/700 range. This conversion for the navy usually comes up with this number and they tried to adapt the same rate of fire for the M1 and M1A1.