I can see there being a very slight advantage of having a gun that is capped at 15bps but can mechanically do 40bps (known as gun A), compared to one that is only capped at 15bps due to electronics and mechanics (known as gun B)
The slight advantage that I can see is that the very first ball will be out the end of the barrel ever so slightly quicker, not because of the velocity differences, but because of dwell times ect.
For example to do one full cycle gun A will take 0.025 seconds (1 / 40), lets say for arguements sake that the time taken for the gun to register a shot, the dwell time for all the air to be released, and the time for the ball to have started on its travel down the barrel 0.018s. And the other 0.07s is the time for the bolt to go back, a new ball to be loaded and for the gun to be fired for the next shot
But gun B which can only cycle 15 times a second, will take 0.067s to do a full cycle and I will pretty safely say that the gun will not have that ball in its same position in the barrel after 0.018s. Therefore meaning the ball will have left the barrel of gun B after the ball has left gun A. Thus slightly reducing the time that your opponent has of moving out of the path of the ball
The flaw with this though is that, well first off the time wont be that huge of a factor I dont think, its a factor but not a huge one. And secondly, guns like cockers have the advantage of already having the bolt forward and ready to shoot.
Just a thought thats all
-Mat