'21 Rate Of Fire Discrepancy

[Bob B]

Just as a matter of interest, I noticed a discrepancy or error in the rate of fire cited for the 1921A. In most of the AOC literature, full auto fire is described as being 300 shots per minute (controlled bursts, not cyclic). However, in AOC's 8-page brochure for the year 1928, full auto ROF is given as 500 shots per minute. The image cuts below show the difference.

 

 

http://img48.exs.cx/img48/4362/ROF_300_500.jpg

[1921A]

1921A Rate of fire

 

300-500 rpm is interesting for the model 21A. Some prototypes including the 1919 had varying rates of fire as high as 1800 rpm. Production 1921As have a rate of fire between 850-1000 rpm depending upon the individual gun. Mine is fast - probably around 1000 rpm. I've owned several 21As and all were high rpm guns.

 

The published rates of fire probably take into account changing marketing strategies. In 1928 AOC was aggressively trying to interest the U.S. Navy in the gun and one of the Navy's concerns was the high rate of fire of the model 21A or AC.

 

Almost all of the AOC literature lists rates of fire lower than they actually were. Who knows why. It was probably a variety of reasons, but one thing we do know for sure is that AOC new better.

 

Greg Fox