ORIGINAL: lemoyne
sproulman
We tested from 44 inches down to 20 inches now you can make a case for the most efficient barrel length being 26 because that length is the point at which you get the most FPS for a gr of powder.
But that's not what I am talking about, first that was black powder if it the test I am thinking about. Second the peak of efficiency can change with the amount of powder as long as you have enough barrel to burn it. Third the peak has two sides to it and it is quite practical to go past the peak if you want high velocity . And last but not least I am burning Blackhorn 209 which has a completely different set of burning characteristics, it burns progressively at a lower pressure for a longer period. Lee
yes,dupont powders were used ranging from 65/120 grs in .45/50 cal
mr.ed yard was the t/c ballistics expert that made test.
test covered velocity and chamber pressures.
CHARGES OF 70GRS RECORDED THE HIGHEST VELOCITY IN RELATION TO LOWEST PRESSURE.
above that showed marked increases in pressure for only MINOR gains in velocity.
this is info if anyone is interested and is about what i use for my roundballs and my powerbelts.