Fellow Big Bore-ians,

Checking the .400 Pondoro loads in the A-Square Reloading Manual shows the following load:

400 grain bullet/76.5 gr RL-12 powder/ 2,367 fps velocity/52,000 psi (avg).

The .400 Pondoro is a .409" bullet on the full-length H&H case. It is not the same as the .400 H&H but the data should be similar. The bullet used was the A-square Lion Load. The barrel length is given as 26", and the pressure reading is from a piezo transducer (SD for the data is 3,000 psi and ES is 5,800 psi).

The .400 H&H is a .411" bullet on the same H&H case, but the two cartridge case shapes are different.

So I offer this up as a model for what the .400 H&H may deliver in pressure.

jim dodd

If that is an accurate pressure model, then H&H has not met its design criteria of offering a low pressure cartridge. Essentially it is a repeat of the 416 remington magnum, but with the H&H taper in the shoulder.

500grains,

The theory of the .416 Remington and the reality of ammunition performance have clashed in Zimbabwe's hot weather as reported in African Hunter. Editor Don Heath has published several accounts of rifles showing very high pressure events with Remington factory ammunition. While I realize that the plural of anecdote is not data (at least until the law of large numbers comes into play), something is going on with their stuff.

Thanks for BTT.

jim

Well,hopefully in 12 to 14 weeks I will have some of this "sorted out". Ordered a barrel from Krieger this week, a no. 6 contour CrMo, with 0.403" bore and 0.411" groove dia. for the 400 grain Woodleighs.

When I chamber this barrel for the 400 H&H and fit it to a Mauser action, I will install a M43 strain gauge and go shooting.

Also have a new Lilja .416 barrel, I am thinking of chambering it for 416 Remington, installing a strain gauge, and testing with some of the popular loads. And I have a 416 Rem that I will build on a M70 with a 12 inch twist Krieger barrel. This one may also be a strain gauge candidate.

Could be interesting.