Been reading this thread with interest, curious what would be said.
Bought a lb of Trail Boss, oh maybe 1 1/2 years, or longer ago. My intent was to shoot cast bullets in my 30 cal rifles, such as 30-06, 308. Also had a 43 Spanish 1879 Remington Rolling Block that I wanted to use it in.
At that time, no published load data for using Trail Boss in 30-06 or 308 with cast bullets, so called IMR requesting load data info for these calibers. Long story short, IMR rep strongly advised me not to use Trail Boss in bottlenecked cartridges, only to be used in straight wall brass like that in most pistol brass, 45-70. Something to do with burn characteristics being different than normal powder. I even PM'd a couple of guys in Australia, since A.D.I. there supplies IMR with the powder, asking if they knew anything about Trail Boss. They'd heard of it, but not used it.
Then a few months later an article appeared in a gun magazine about Trail Boss and lo and behold, writer had load data for 30-06 and 308 with cast bullets. Turned out, what I thought would be a start load with TB in the 30-06, close to what article said to use.
With purchase of 2010 Hodgdon's reloading data magazine at a Wal-Mart last January, I read its article about use of Trail Boss with not only cast bullets, but also jacketed bullets. LOL Article quoted head ballistician at Hodgdon about "being impossible to over load a cartridge with T.B." and later he was quoted about how to find optimum accuracy with trail boss and a jacketed bullet in your rifle.
Quite simply, take a piece of brass, mark outside of case where bottom of jacketed bullet you want use will be in case/neck. Fill case with T.B. to your mark and then measure grains of T.B. it took. Ok, lets say it was a 270Win brass and you've measured it took 20 grains of T.b. to reach your mark on the brass. This is your 100% load density. Hodgdon Ballistician then said to calculate what would be 70% load density. This is done simply by multiplying the number of grains it took to reach your mark, which in this example is 20 gns, times .7. So 20 gns X .7=14grs. This is the 70% load density and it would be your start load. Somewhere between the 14 gns and 20 gns in my 270 Win example, you will find a load that works best for bullet you are using.
Chuckle, I just take a lee dipper that will fill whatever cartridge I'm reloading to its shoulder with T.B. and seat the bullet. No rocket science here and I have a good time shooting with T.B.
Final word. I posted about Trail Boss on Surplus Rifle.com shortly after getting the Hodgdon 2010 reloading magazine, mentioning its very mild recoil. Gent there, who had a heart problem/pacemaker or something that prevented him from shooting his collection of bolt action surplus military rifles, because of their recoil, read the post. He tried the Trail Boss a few days later with excellent results and is now shooting his Surplus rifles regularly. So happens the gent teaches a community college reloading class and mentioned he kinda hated to tell his students about Trail Boss.....that he was afraid one of them would think all powders could be safely loaded to 100% density like Trail Boss.
