Harry O
06-16-2013, 01:10 PM
I bought a couple of new-model Vaqueros in .45 Colt recently and was experimenting with Trail Boss powder. The IMR booklet shows 5.8gr maximum with a 250gr bullet. With Starline cases, the brass did not even seal until 7.2gr. There was blowback along the case for everything less than that, and the accuracy was very poor with the ones that had blowback. Once the case started sealing, the loads got a lot more accurate.
I had loaded up a bunch in increments to 7.5gr. There was absolutely no sign of excessive pressure on the cases, the primer, or the gun at 7.5gr. After shooting them, I decided to go back and load up a bunch more up to 100% of the case capacity with the bullet seated (no compression)
That amounts to about 8.0gr with a 250gr bullet. That is case full without compression. The accuracy was about the same for all of them. If anything, they may have grouped a little bit tighter with more powder, but I would have to do a lot more shooting to tell for sure. In any case, they were accurate enough for CAS shooting. With the 8.0gr load, the primers were just starting to flatten, but were no where as flat as factory loads for a lot of higher pressure cartridges. The flattening was not at all excessive.
I think that the bullets I have are not well suited to this cartridge. They ONLY thing I was able to buy was some 250gr Barnes plated bullets. I have had a mould on backorder for 2 months now. When it gets in, I plan to cast up some in BHN 9 or so to try. I would be willing to bet that those would seal better and be more accurate, maybe even at lower amounts of powder. I have not chrono'ed the ones I have shot yet (it was in a public indoor range), but from the recoil, I would guess that the velocity is less than 900 fps at 8.0gr. I am also thinking of getting a 230gr flat nose mould and go up to 8.5gr of Trail Boss -- if it is ever possible to buy something without it being backordered.
Anyway, just a report on going over the recommended loads in the IMR manual with Trail Boss.
I had loaded up a bunch in increments to 7.5gr. There was absolutely no sign of excessive pressure on the cases, the primer, or the gun at 7.5gr. After shooting them, I decided to go back and load up a bunch more up to 100% of the case capacity with the bullet seated (no compression)
That amounts to about 8.0gr with a 250gr bullet. That is case full without compression. The accuracy was about the same for all of them. If anything, they may have grouped a little bit tighter with more powder, but I would have to do a lot more shooting to tell for sure. In any case, they were accurate enough for CAS shooting. With the 8.0gr load, the primers were just starting to flatten, but were no where as flat as factory loads for a lot of higher pressure cartridges. The flattening was not at all excessive.
I think that the bullets I have are not well suited to this cartridge. They ONLY thing I was able to buy was some 250gr Barnes plated bullets. I have had a mould on backorder for 2 months now. When it gets in, I plan to cast up some in BHN 9 or so to try. I would be willing to bet that those would seal better and be more accurate, maybe even at lower amounts of powder. I have not chrono'ed the ones I have shot yet (it was in a public indoor range), but from the recoil, I would guess that the velocity is less than 900 fps at 8.0gr. I am also thinking of getting a 230gr flat nose mould and go up to 8.5gr of Trail Boss -- if it is ever possible to buy something without it being backordered.
Anyway, just a report on going over the recommended loads in the IMR manual with Trail Boss.