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View Full Version : .30 and .31 Case Capacity Experiment



NVcurmudgeon
03-29-2008, 12:52 AM
I shoot a lot of CB loads in five different cartridges using the same load. .308, .30/40, 7.65 X 53 Mauser, and .303 British all give MV very close to each other, with the somewhat larger .30/06 a little slower. The load is 16.0 gr. Alliant 2400 and Lyman 314299 sized differently for each rifle. I made a rough comparison of case capacities using Winchester 748 ball powder. Yeah, I know water and weighing would have been more scientific, but "what you see is what you get," and what you get is what I had patience for. All cases were filled by gently pouring powder in the case up to the bottom of the neck. Powder was not settled or tamped down. The .308 and .30/40 held 50 grains, the 7.65 Mauser 50.5, and the .303 British 51.7. No adjustment for seating depth was made, and all powder levels were in accordance with a precision calibrated eyeball. I didn't check the capacity of the .30/06, just the four I suspected were about the same.

runfiverun
03-29-2008, 12:32 PM
add the 7.7x58 in here as well

dualsport
09-16-2012, 01:16 PM
You could say when it comes to rifle cartridges "the wheel" was invented over a hundred years ago. Since then the only major advances have been in the strength of the guns. What can you do today with a modern military sniper rifle that you couldn't do in 1891? I just love my old milsurps too much I guess.

I'll Make Mine
09-16-2012, 09:43 PM
What can you do today with a modern military sniper rifle that you couldn't do in 1891?

Pretty much the only thing is reach out past a mile -- as you say, strength of the gun lets you get that last couple hundred feet per second, though I'd say bullet design has improved this aspect a bit, too; modern long ogive boat tails hold their velocity better than the round nose, flat base bullets used in most "state of the art" military cartridges of 1891, which makes them easier to deliver in another zip code.

The Mosin Nagant 91/30 (differs from the original 1891 in having sights calibrated in meters instead of arshins, and a couple inches shorter barrel), with the right loads and a good scope, can hit man sized targets out to half a mile (800 meters) with aplomb, and struggle along to 1000 m; a modern .300 Win Mag sniper rifle can reach out to 1500 m in good conditions (and a .50 BMG Barret can go out to a mile and a quarter, if the target doesn't decide to take a step while the round is en route). Not really that much improvement for 120 years, compared to how far we came between 1770 and 1890...