Several loads listed in my reloading manuals list loads that seem very high pressure. The particular load I've used for the last 30 years runs at a listed 62,000+. Why is this? I've never had any type case failures that would indicate too hot of a load. Case life is always excellent. Why does the .338 Win. Mag. run such high pressure when most other calibers run 10,000 cup less?

I think you might be comparing your .338 pressure in PSI to some other magnum in CUP.

There's a couple of reasons. One is that CUP (Copper Units of Pressure) and PSI (Pounds per Square Inch) aren't measured with the same equipment. So the numbers don't come out the same, with PSI usually higher. There's a rough correlation between them, but it's not reliable enough to predict pressures.

The second reason is that some cartridges are commonly chambered in older guns that aren't capable of handling the pressure a modern bolt action can. This applies to the .30-06, which was chambered in the Springfield 1903 rifle and the Winchester 1895 rifle.

Many cartridges have both a CUP and PSI listed. CUP for the .338 Winchester is 54,000 and PSI is 64,000, according to the Alliant 1996 Reloader's Guide.

Check out this thread for more.
http://www.shootersforum.com/showthread.htm?t=21362

Bye
Jack

--I guess what really concerns me the most is my Tikka White Tail Hunter's bolt only has two lugs, and I wonder why they would chamber a cartridge that runs higher than 50,000 cup? I'd think that even at 54,000 the design might be stressed some. So far there's no bad signs but I've always wondered what the practical pressure limits are for this rifle.

--I guess what really concerns me the most is my Tikka White Tail Hunter's bolt only has two lugs, and I wonder why they would chamber a cartridge that runs higher than 50,000 cup? I'd think that even at 54,000 the design might be stressed some. So far there's no bad signs but I've always wondered what the practical pressure limits are for this rifle.

Mr. C,
The number of lugs is not a good indicator of strength of the action. Your CZ, and many other rifles (Win Mod 70, Rem 700, Mauser 98, Savage to name a few) all have "only" two lugs. All of these rifles have been chambered for the 65,000 psi cartridges. It is the size of the lugs, and the strength of the steel that determines overall bolt/action strength. Looking at the Weatherby Mark V action, with 9 locking lugs, you'll note that the lugs - by necessity of geometry and action size limits - are much smaller. Along with pressure, there is consideration for the cartridge diameter and increased bolt thrust (for larger diameter cartridges), but be assured, manufacturers have it together. Don't worry about your CZ, it's plenty strong. You only have to worry about this if you're wildcatting.

Many of these two lug bolt guns are proofed in excess of 125,000 psi. Lots of folks just pushing loads and wildcatting are well exceeding design pressures in a multitude of bolt guns.

I can well remember loads that were hot enough to make opening a bolt sticky upon opening. These loads were easily approaching 75,000 psi.

I wouldn't worry about using any factory load in a modern bolt gun.