Originally Posted by -=ArchAngel=-
... A lighter round with a faster speed may have its potential if its able to maintain most of it's initial speed during extended flight.
Only if it has a better ballistic coefficient. I've seen nothing that supports this being the case.
121 round has a Form Factor (nose and tail shape) equal to or worse than an FS round.
121 round has a weight worse than an FS round (this is a fact so far as published, and I believe I heard the rep at LL say 2.x grams)
121 round has a diameter approximately the same as an FS round (this is fact so far as published).
The round will definitely fly worse than an FS round.
Assuming that the Form Factor (i) of the 121 is the same as the FS round (.9070), the weight is 2.3grams, and the diameter is .685 (like an FS round):
Form Factor (i) = .9070
Weight in pounds (M): .0051
Square of Diameter in inches (A): .685^2 = .4692
SD = M/A
BC = SD/i
Solve for SD:
.0051/.4692 = .0109
Solve for BC:
.0109/.9070 = .0120
For comparison, here are other BC values:
.683, 3g paintball: .0057
SA 121 Round: .0120
First Strike Round: .0162
This is of course assuming that the form factor is not degraded by the forward shell lip, or the skirt shape/condition, and that the centes of gravity and pressure allow the round to be stable in flight.