Quote Originally Posted by Dimitri View Post
That is the point me and Ed are trying to make nothing more.



I went to college for Tool and Die, and learned both in school and at work about the properties of metal, heat treatment and the selection of proper materials for the job and the abilities for metals to withstand excessive forces that they were not designed to do if that counts.

I say the 4% or so difference in pressure between the No.4 chambered in 303 Britishicon and the 308Win is not enough to worry about it. Actually its so trivial that if I was to mention this to anyone I know with decades of experience working with the properties of materials that they'd tell me I'm a idiot. Not a personal insult to anyone, just a fact. No design is within 4% of breaking or failing.
13,000 PSI is a lot more than 4% of 49,000 PSI.



No one would, that is being stupid, look at your reloading manuals I doubt any 308Win max load will reach 55,000PSI. Now look at that same reloading manual where the Winchester Short/Super Short Mags and the Ultra Mags are listed as 62,000PSI loads.

Dimitri
Reloading manuals are suggested safe loads, they don't mean that no factory ammo can exceed those suggested loads. As Ed's post above shows pressures can vary by thousands of PSI within the same lot.
One can load a cartridge to as low a pressure as they wish.
55,000 PSI is over ten percent higher than any loading deemed safe for the .303. Also loads tested with one brand of cases can generate much higher pressures if a different case with smaller case capacity is used.

The 7.62 NATO chambered rifles would be safest if used only with taylored handloads that did not exceed the 49,000 PSI Maximum SAAMI specs for the .303.