I have been running pressure & velocity trails with the 400 Holland & Holland, using a strain gauge system.

Preliminary data is very impressive, to say the least.

This appears to be a much more efficient case than the 416 Remington.

I have a set of reamers and much data on the 400 H&H.

If there is any interest, post a reply, and I will consider posting more details.

PS, I have been reading NitroExpress for some time, but this is my first attempt at posting. Looks like a good forum!