Any ideas ?

[Cold Spring]

Originally Posted by Dave Noreen

In the Western Cartridge Co. Super-X booklets of the 1920s and early 1930s Capt. Chas. Askins states the velocity of the 3-inch Super-X is a bit over 1000 fps over forty yards. The 1941 Winchester Ammunition Guide gives the velocity over forty yards for the 12-gauge, 3-inch, Super-Speed, 1 5/8-ounce load as 965 fps.

Another shotshells ballistics chart I have shows the muzzle velocity for the 1 3/8-ounce load as 1295 fps and the 1 5/8-once load as 1200 fps. I have no attribution for this chart.

As for pressure they would be withing SAAMI Specs.

Actually, the answer is likely zero and zero. Those pre-war non-corrosive primers have likely exceeded their useful life.

Data I've seen shows the pre-War 12 ga/3-inch/1-5/8 ounce load at 965 feet AVERAGE over 40 yards, and the very same load did 1315 feet "muzzle velocity" after the War when electronic chronographs came into use. That second number is considerably higher than posted by Dave. Both as tested with number 6-shot.

[6pt-Sika]

Originally Posted by Frank Srebro

Data I've seen shows the pre-War 12 ga/3-inch/1-5/8 ounce load at 965 feet AVERAGE over 40 yards, and the very same load did 1315 feet "muzzle velocity" after the War when electronic chronographs came into use. That second number is considerably higher than posted by Dave. Both as tested with number 6-shot.

Maybe the 965 wasn’t at the muzzle but out a bit ?

[6pt-Sika]

Originally Posted by Frank Srebro

Data I've seen shows the pre-War 12 ga/3-inch/1-5/8 ounce load at 965 feet AVERAGE over 40 yards, and the very same load did 1315 feet "muzzle velocity" after the War when electronic chronographs came into use. That second number is considerably higher than posted by Dave. Both as tested with number 6-shot.

I’d be okay with 1300 at the muzzle !