doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Why do older guns require low pressure loads?

Hi:

I have been cautioned to use "low pressure" loads in my N.R.Davis SXS. What makes a gun to require "low pressure" loads? Is it weak design, inferior materials, poor machine work/ tolerances etc.?

I have read that Damascus barrels are as strong as any despite what many will say. Do these require "low pressure" loads? Some of these old guns have been proofed at very high pressures!

What problems can happen if one does not use low pressure loads in an old gun? Will the action crack, a barrel split will the gun be off face etc? Has anybody ever split a stock on a boxlock if the stock was tight and well fitting via a high pressure load?

TIA,

Franchi

Actually more important to the well being of your vintage shotgun is to keep the recoil within a reasonable range which is often equated to low pressures. In many cases you are shooting a gun that is well over one hundred years old and during that time wood drys out and become brittle, solder on ribs and forend hangers ages and become brittle. It is true that Sherman Bell found that damascus barrels could withstand a tremendous amount of pressure but why push the odds when low to moderate pressure and recoil loads are available.

So you can count to 10 on your fingers. LOL

Franchi, you're talking about an American gun, where really low pressure may not be quite as important as it is on older British or European guns. Our guns were, in general, built stronger--more like tools. That's especially true of guns like Davis, Stevens etc. But back in the 1920's, when Olin came out with the Super-X shell, that raised standard working pressures about 1,000 psi over what they had been previously. So it's a situation of guns not designed for the pressure of modern shells, having suffered some ravages due to age, and metallurgy having improved quite a bit since before WWI. All reasons to hold down pressures at least somewhat, even in older American guns.

When I was 30 I moved a piano on my own, with some blocks and boards I got it into my house. Last year I tried to get it out of my house .I couldn't manage it . I guess its because I'm nearly 30 years older. The answer to your question ,with out going into reams of discussion about metallurgy ,discussions on weather the gun in question had a forged action the quality of the barrel steel,metal fatigue,build quality etc.etal. Its old and was probably never expected to take heavy loads or to have lasted so long.

This is a gun from the late 1940's No problems were visible until the locks were removed. Wood will only take so much punishment....



Pete

Thanks for the answers! I like Mike Harrrels answer!

When I was a youngster, a nice older gent would take me hunting. He had all of his fingers on his left hand blown off by a shotgun while hunting one day.

He had no idea as to what happened but he was sure of the result. The gun was not plugged with anything when he fired it. It just blew up! I never forgot this "lesson" about shot gun operation and to this day, I try to remain on the cautious side!

Franchi

Older shotguns require lower pressure loads for the same reason that older men need VIAGRA -- some important parts have weakened over the years, and aren't as strong and hard as they once were!

Pressure will not crack stocks, but excessive pounding will, especially if the wood is old, brittle, oil soaked, or all of the above.

Pressure will exert more force upon bolting surfaces, hinge joints, and the receiver itself. Barrels in good condition will usually take a surprising amount of pressure before they fail, but one failure can end your shooting career in a split second.

Turn of the century guns were built of milder steels with less refined metallurgy, alloying, and quality control than is common today. They were built to handle the loads in common use at the time. Most importantly, some action designs are better able to handle a multitude of shots at maximun design pressure before they wear or break. If we could find a new in box N. R. Davis and a new in box Winchester model 21 and began firing the same 12 ga. RST low pressure loads in them, most everyone here would bet large money that the Model 21 would still be tight and sound when the Davis was worn out. Jump up to standard pressure loads, and the Winchester will hardly hiccup while the Davis will slowly be pounded to death. Once the wear starts and bolting surfaces are peened and deformed and the gun gets loose, the rate of additional damage will accelerate. Certain designs are just better than others. Cheap guns of poor design and materials just don't stand the test of time unless they spend most of that time sitting in a closet unfired.

If your Davis was properly put back on face and you use conservative loads in it for hunting, it will probably outlast you.

Jerry, I was not aware you'd been buying guns that have barrel droop!