Ray think about it...
The cycle time of the bolt is fixed.
The rof goes up, as the rof goes up with a fixed cycle time you get a smaller and smaller time window to feed a ball, thus you need to feed faster and faster out of the loader to get the ball into the breech in that small window of time.
When shooting at 13bps you can achieve this with a loader feeding at approx 17bps.
When shooting at 30bps your loader needs to be feeding at around 60bps...
been a while since I did the numbers but I think I remember those as being approximately correct
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