Lesson Learned - - - - Again

If you scroll down to my range report below, there's a couple things that I'd like to bring to your attention.

The Remington 210gr bullet had virtually no change in chronographed velocity when the powder charge was reduced from 8.5 to 8.0 grains of Unique. I conclude that the powder did not fully burn in the 4" of barrel length, so a reduction in powder charge is indicated.

The 210gr Rem bullet was chronographed at about 1040 f/s on average. The Sierra reloading manual was used as a reference. According to Sierra the velocity should have been around 950 f/s with 8.5 grains of Unique with the Max at 8.8 and 1,000 f/s.. My Hornady manual, that I failed to reference maxes out at 7.0 grains of Unique and 850 f/s. Since I was shooting Remmington bullets I was remiss in not checking all my manuals and using the lowest Max charge as the Max charge and reducing from there.

The Sierra 240gr bullet averaged at about 975 f/s with 7.5 grains of Unique. The Sierra manual says the velocity should be about 825 f/s with that charge. This isn't the first time I've found this sort of thing. This is why I bought a chronograph in the first place. Way back when, I worked up a nice accurate load for my .357. In the hot days of summer the cases would tend to stick in the cylinder, one of the high pressure signs. My then brand new chronograph indicated higher than expected velocity. Since high pressure and high velocity go hand in hand I reduced the powder charge. No more sticking cases. So even with Sierra bullets, my particular gun generates more velocity and higher pressure than the Sierra manual shows. Using the ratios of velocity and powder charge, I'll calculate a new maximum powder charge for my particular revolver when using that bullet.

All the writers say to start at the minimum powder charge and then work up from there. But I just can't make myself do that. I always start at some charge between the midpoint and the Max. Saves me a lot of time and money that way. I've found that the best accuracy usually falls in that same area. The down side is that some guns will produce pressures higher than the manuals indicate. Of the many cartridges I load, and the couple dozen guns I shoot, this has happened only 2 times. This was number 2.