First:
Once again I will post that the Rebs, in the 1860's, test fired their Colt 36 copies with 165 grs powder and double balls, wadded.
That is within 3/4 inch of the muzzle. They held. And they were brass framed.
That's what you misread, Smoke. Easy to overlook.
Actually, they test fired their muskets or rifles with 465 grs powder, when 232 was the standard English proof load. AND THEY held, too. I think these were 1858 Enfields. Have to read the book again, don't want to.
Ferret,
I have been preaching this, and getting grief for it, but just because a maker scribes some marks on a measure does not mean it is what is actually being thrown. BP is the standard for a measure, you weigh a charge thrown from your measure, and if it is on, great, if it is off, you have to scratcha new mark, and know that is the actual 20, 30, 40 grs weight of BP, and volume of any other, by equivalent. Weight/volume of BP is the same, weight/volume of any sub is different.
I have too many that are not accurate, now have 3 that I can trust, but only because I measured then weighed, and the charge was within a grain or so of the marks on the barrel of the measure. That can be the settlement of the powder, or lot to lot variation.
As to the cylinder gap opening up, well, yes it does that, it will do that with 10 grains of powder. You will get blowby then, too. If you have a 6 thou gap, at 10 grs, you will have 6 thou at "60" grs, too. More pressure, so more fire at the gap. More from the muzzle, too. Unburnt powder, more so called "ejecta", which is another word for weight of load, which has to be both the ball and the powder.
Smokeless does that, too. You have to add the powder weight to the weight of the ball to calculate recoil. Consider, a potent blank has recoil. Not just noise.
Sundance,
777 is lighter than BP and most others subs. 60 grains weight would spill all over the place, no chance you could fit it in the chamber TO compress it. You'd have to dump powder, compress, somehow, dump more, compress more, finally dump the rest and seat a ball, IF it were possible.
The whole thing is academic, as Ferret says he checked his measure and found that measures are less reliable than teaspoons for accuracy.
Anybody checked HIS measure against a scale, who HAS BP to use as a standard? If you don't you could use Ferret's weight of the 30 gr charge, from his measure, that is actually 23 grs. And that is BP.
As I have often said, though I should quit it, you load a normal load, per your way off measure and say, "Wow, it is a mild shooter.", you load a MAX load and say "Well, hot as hell, but no recoil to speak of." That extra 10 grains to get to max will make you wince. My Rems shoot harder than my Colts with the same measure. Think it is the difference in groove diameter. More resistance to travel up the spout. Kicks just a bit more, sounds a LOT louder, shoots flatter.
Cheers,
George