17pr HE Super HC-/T question

[Nabob]

Attached table says that Mk2 differs from Mk1 that it is low windage.
Shell design numbers and weights are the same.
Could someone explain the "low windage" term to me, please.

Thanks, Bob

 

[TimG]

Windage is the space between the projectile body and the bore of the barrel. The lower the windage the smaller the gap. The less probability of the projectile to wobble and thus more accurate. In worn barrels one can get 'slap' where the top of the projectile gets engraved with 'rifling.' I suspect some of the figures on that page might be incorrect and subject to an amendment.

TimG

 

[Nabob]

Thank You Tim.
Bob