doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com 7,981 psi shells in an old gun

As I read the above, I don't think Buzz is interested in anything like the Subsounds for grouse hunting, since he wants to use something hotter than the B&P 2000--which, in turn, is hotter than the Subsound. Assuming "subsound" means subsonic velocity, I wouldn't want to use them for hunting either.

Buzz, 8,000 psi should not be a problem in an old gun. I'd also point out that if you have a gun with a proof of 3 tons, while the gun may be 100 years old, it's been subsequently reproofed, and the current proof is maybe half that age, or perhaps less. I have fired heavier loads than that in a game gun on driven shoots, and I regularly shoot wild pheasants over dogs in this country with 1 1/16 oz Gamebore loads, usually backed up by my own 1 1/8 oz reloads (around 7,000 psi) in the tight barrel. All of those will give you more of a jolt than what you probably shoot at targets. But on the other hand--except perhaps for a driven day--you won't be shooting nearly as many of them either.

Just by way of comparison: Going from an 1160 fps load to 1260 fps, both 1 oz, you will see a 20-25% increase in recoil.

Thanks Larry. I was hoping you would chime in. Your info is what I was hoping to hear. The gun has replacement barrels with Birmingham proof marks with 3 ton.....they were replaced sometime in the 60's I believe. Rook: the high pheasant shells are 1280 fps with 8416 psi. I have 2 boxes of those shells and may try them, but I'm wondering if they wouldn't be harder on my gun than the 2 3/4 inch sporting clay load at 7981 psi. I think 7981 psi is not that terribly much chamber pressure for a shell with 1260 fps muzzle velocity.....lower pressure than I would have guessed. Thanks to everyone for the opinions!

What is the chamber length? Did I miss that?

Rookhawk,
Now I know why B&P is always out of the F2subsounds when I try to order some....think I'll tell Kari to short your next order a couple of cases! The Winchester AA featherlites 24gram at 980fps is also a good load. I've used it on 16yd and mid-range handicap trap, skeet, and it is devastating on doves.
Gary
"You're either on em' or you ain't." the late, great Uncle Robert Brister

I posted this on the 16g site in 2008. Can anyone confirm now?

Baschieri & Pellagri CIP data BUT you must add 500-1000 psi to the reported pressure to get an approximation of the SAAMI equivalent PSI. The 16g F2 Classic is factory listed at 9,867 psi but testing by Tom Armbrust showed it to be 10,500.
http://www.bandpusa.com/content/Speed-and-Pressure-Chart.pdf

'.. ..BUT you must add 500-1000 psi.. '. Huh???? What?? Well, if that is true, then B and P is totally misrepresenting their product to the United States market. Drew, are you absolutely certain their actual pressures are really 500-1000 psi higher than what they state? Pounds per square inch has the same definition and meaning in Italy as it does in the U.S.!! If this is the case, then this represents a fraud on the part of B and P IMHO.

Apparently CIP measures psi using a different technique than SAAMI, and B&P reports CIP. There was a long thead here in 2008, but things might have changed

There are three pressure measurement systems (lead crushers/LUP, copper crushers, and piezo), and two standard systems of measure units (USA/SAAMI and CIP/British/European) and two differing units (psi and tons and bar and Kg/Cm sq) within each system.
Unfortunately, there is essential NO formula to convert BAR expressed as LUP (CIP) to PSI (SAAMI).

Bro. Larry should be able to help as this is way over my head

British 3 ton lead crusher pressure is about equal to 9,000psi Piezo Electric pressure. I do not have a comparision for CIP crusher pressure.

There does indeed remain the problem of language dividing us from our CIP cousins across the water. That's true not only of pressure, but also of velocity. When we speak of "muzzle velocity", it's actually measured 3 feet from the muzzle. The Brits either use true muzzle velocity, or--more commonly, at least in older Brit references--the average velocity over 20 yards. More recently, I've seen reference to velocity readings taken 2.5 meters from the muzzle. I wish they'd just pick one way and stick with it!

Re pressure, I don't know of any conversion factor for the old "tons" proofmarks the Brits used. A bar should equal 14.5 psi. However, when the Brits used bars--the previous 850 bar (etc) proofmarks--those were actually crusher bars, not measured with an electronic transducer. Therefore, it was like the old LUP figures you see in reloading manuals: no direct conversion. I have an email from the British proofhouse indicating that the 850 bar proof pressure converts to 960 bars piezo, or 13,920 psi. As for pressure expressed in psi, I thought in that area, at least, we were on the same sheet of music--since psi measured via crushers isn't really psi at all, but rather LUP (or CUP, if a copper crusher is used).

Maybe time to send Armbrust some more of those evil ferrin shotshells!