Cylinder choke

[Westward]

Identical density, suggests identical material used to make the pellet.

I thought it reasonable to assume that and also the same muzzle velocity.

If the pellets have the same density, (same material) then the smaller pellet will have less mass, so will slow down more quickly, when fired at the same speed.

No. Pellets are slowed by resistance to air and since the smaller pellet has a smaller frontal area it won't slow down quicker than the larger pellet. In this scenario pellet density is what matters and relative mass is irrelevant.

If you drop  100Kg lead ball and a feather in a vacuum at the same time, they will fall at exactly the same rate and hit the ground at the same moment.

This is why steel 9's, have to be fired faster, to retain a similar energy down range, as lead 9's.

Steel is lower density of course therefore less mass for a given shot size.

I don't dispute Will's findings; no one can argue against empirical results, but I wonder if the comparisons were based on like for like shells where the only difference was pellet size.

 

[Skeet UK]

@Westward@Hermit

BC of #9 (2mm) shot, weighing 0.75gn is 0.011369

http://www.shooterscalculator.com/ballistic-trajectory-chart.php?t=a4738c5e

BC of #7 (2.4mm) shot, weighing 1.28gn is 0.013474

http://www.shooterscalculator.com/ballistic-trajectory-chart.php?t=c9732bf5

Both launched at 1300fps.

The #7 shot retains 731fps at 40 yards and wind deflection of 7.15 inches

The #9 shot retains 682 fps at 40 yards and wind deflection of 8.21 inches

 

[k80ben]

Put it in the right place will break anything