Same old dangerous BS by keyboard toughies, who often don't know jack squat about the guns (or barrel/ breech strength that the load will be used in. What do you know of the metallurgy and what it might take to work harden the alloy. Years ago a barrel maker made specific target barrels for certain matches, 62 caliber rifle barrels that were only 7/8's acf and intended for offhand shooting with no more than 35 grains of 2fg. A stooge who decided to magnum load that barrel now has a skull plate of stainless steel and the mind of a 4 yr old. Likewise Dixie sold thousands of thin wall barreled shotguns 50 yrs ago that weren't safe with more than minor loads of 2 or 3 f. I have a pistol for which the manufacturer suggested load. is 2 times more than most manufacturers' max rifle loads, but the barrel is almost 2 inches across the flats for 75 caliber. But I would never tell anyone to load that much in just any pistol, they might be unwise enough to use that much powder in one of those old sheet metal thin twist barrel Belgian pistols that Dixie once sold. .
So please tell us the breech pressure from 4 fg in a 50 caliber smooth bore under a column of shot. And specify which manufacturers barrels are so strong that the makers suggest 4 fg loads. What's that? no barrel makers suggest that? I would tend to believe the barrel maker himself rather than some key board toughie.
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