Military zeroing of the No. 4 - inconsistent data?

[Bindi2]

Rick
It is not the BC it is the cordite burn rate pressure curve that is the issue. Also the open base changes things in cordite used barrels that flat based cant copy. Depending on how used the barrel is boat tails may not work at all. Forget trying to make it a vermin shooter or use 3031 to emulate cordite. .312 projectiles will be your friendly ones. I convert 174g OBBT to straight 174g BT to solve the cordite barrel issue but can not get a perfect match to Mk7 on the drop sheet. As said else where have fun.

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[Rick]

Rick
It is not the BC it is the cordite burn rate pressure curve that is the issue. Also the open base changes things in cordite used barrels that flat based cant copy. Depending on how used the barrel is boat tails may not work at all. Forget trying to make it a vermin shooter or use 3031 to emulate cordite. .312 projectiles will be your friendly ones. I convert 174g OBBT to straight 174g BT to solve the cordite barrel issue but can not get a perfect match to Mk7 on the drop sheet. As said else where have fun.

Thank you and others for reminding me to pass on the cordite info.

I had already passed that on to him, along with the Canadian/British sighting data also found here during my searches. It would be hard to miss the various threads on how it is impossible to reproduce Mk VII ballistics - and part of the problem being cordite - during the website searches I did here for zeroing information to pass along to him. I never even tried to replicate MkVII ballistics with my handloads; having a PH4 vernier sight on top, seemed irrelevant to me. Now that 90% of my shooting is 200 yards with powder coated cast bullets, it means even less.

Anyways, he already knows he's embarked on an impossible task that more than a few here have already attempted before. Next time we talk, out of curiosity I'll ask him what his ultimate goal is, assuming he agrees it is impossible to match service ball ammo.

He was seconded to do some SAI work with the Canadian Rangers, and when the Rangers just converted to the new Tikka, one of the Rangers he had become acquainted with who kept their Long Branch despite having no interest in keeping it, gave it to him as a gift knowing of his interest in the rifles. According to him, the rifle is in fine shape - he gloated about that for a while when he told me about it.