How high of pressure would you feel comfortable loading?

I was looking at Hodgdon website and some loads exceed 13,000 PSI on 3-1/2" 12ga shells. That seems a little on the high side for me.

What do you think?

SAAMI specs are higher for 3-1/2 in. 12 gauges than for 2-3/4 in. or 3 in. chambered guns.

It is no issue.
Instead of 11,500 PSI to work with, the SAAMI spec was increased to 14,000 PSI for 3-1/2 in. shells only.

That SAAMI would raise pressure specs for the 3 1/2" shells is non-sensical as there is nothing about the shell or gun that allows it to operate at a higher pressure than a shorter 12 gauge shell. But then many of the SAAMI standards are non-sensical. However, the 3 1/2" SAAMI specs probably do not exceed standard specs that many foreign ammunition producers use.

For many years, foreign-loaded shotshells have run higher pressures than American standards call for. Some Americans using their gas autoloaders overseas with locally-produced ammunition have found it necessary to have a smaller gas port installed to compensate.

Handloading shotshells to higher-than-normal pressures can be dicey. Unlike rifles, where the brass will fail far before the steel of the action or barrel will give way, shotgun barrels and actions tend to be weaker than the shells themselves. In other words, with a rifle cartridge you get warning signs like pierced primers or flowing brass far before pressure reaches the point that the physical integrity of the gun is compromised. With a shotgun, you may suddenly find a hunk of steel missing from one side of the chamber where the shell blows out!

Keep your sphincter properly puckered when loading shotshells beyond known standards.

quote:

Originally posted by Stonecreek:
That SAAMI would raise pressure specs for the 3 1/2" shells is non-sensical as there is nothing about the shell or gun that allows it to operate at a higher pressure than a shorter 12 gauge shell.

Of course there is: the minimum yield and tensile strength of the steel and the wall thickness of the barrel must accomodate those pressures, and the guns made for 3-1/2 in. shells are proofed to the higher standard.

There are many shotgun factory loads that go to
15,000 psi, like Rem buckhammer slug loads.
Our 4759 powder reloads for 600 gr slugs
in our 12GA FH research, tested 14,675 average.
That is with regular plastic cases.
In some instances it tells pressure on
the cartridge box.They show the pressure in
BARS in which a BAR is equal to 14.7 psi.
Modern guns are tested on average about
2000 Bars.The new Zoli OU was tested at
Italian proof house at about 7000 Bars.Ed.

1 bar = 14.50326 psi .

Thanks for exact figure. The modern shotgun is quite strong as they use alloy steel and
not cast iron so much.Anybody wanting to
teat shotgun loads, 20 bucks and 4 of
the same loads for average, sent to Tom
at Ballistic research is the way to know.Ed.

A Look at Shotgun Pressures

FWIW.