Harry O
05-23-2013, 08:43 PM
Just before the second Obama buying craze hit the firearms industry, I was lucky to buy a matched set of new model Ruger Vaqueros in .45 Colt caliber at a good price. Early on in the buying craze, I was able to get a set of RCBS dies at a normal price and shortly afterward, 200 brand new Starline cases at just little over normal prices. However, I did not have a mould and have not been able to buy one. Just recently, I ran across a couple of boxes of Berry's plated 250gr FP bullets for the .45 Colt. Not ideal, but better than nothing. Deciding on the powder was not a problem. I bought a 5# container of Trail Boss about a year-and-a-half ago that I have been using for CAS shooting since then. There is still plenty left.
Now it was time to assemble a load so I could try out the guns. The IMR loading manual suggests a maximum load of 5.8gr of TB with a 250gr lead bullet. From past experience with TB, I started out at 6.0gr. and loaded up 10 of them. Then 10 with 6.5gr, 6.9gr, 7.2gr, 7.4gr, and 7.5gr. Five shots were fired from one gun and five from the other gun. They do not impact at exactly the same place, but are very close.
The first 10 shots (with 6.0gr) did not seal the chamber. There was severe blowback (soot) along the front of the cases. The accuracy was poor, too. The group was fairly round, though. Next up was 6.5gr. It did not seal the chamber either, but the soot at the front of the cases was less. Accuracy was still poor. Then I went to 6.9gr. That load pretty much sealed the chamber with only a small amount of soot remaining. Accuracy was still poor, but just slightly better.
Then I moved to 7.2gr. The chambers sealed with that load and the accuracy was considerably better (about half the size of the previous three loads). I can live with that. 7.4 was up next. The chambers stayed sealed and the accuracy was just slightly worse than the 7.2gr load (maybe 60% of the size of the first three loads). The 7.5gr load was a repeat of 7.4gr. Interestingly, the 7.5gr load did not fill the case to the base of the seated bullet. Recoil was mild with all loads. There were no signs of excessive pressure on anything (case, primer, ejection, etc).
I measured the hardness of the Berry's bullets, first with the copper in place (Bhn 16-17). Then I filed off the copper and remeasured it (Bhn 11-12). I am thinking that the plating makes the bullet too hard for Trail Boss. When I am able to get a proper mould, I will cast up some bullets at Bhn 9 to 11 and try them. I am still concerned that anything under 7.2gr will not seal the chamber, at least with Starline cases. For the Berry bullets, I intend to try a bunch more from 7.5gr to 8.0gr. Somewhere around 7.8gr to 8.0gr, the case should be full without compression. I don't intend to try it with any compression.
Interestingly, the center of the groups did not move much from 6.0gr to 7.5gr. Slightly higher with heavier loads is all. All the groups are all a little low and to the left, which can be adjusted with a file when I have decided on a load. I have not measured the speed of any of these yet. When I get an accurate load I will check it.
Now it was time to assemble a load so I could try out the guns. The IMR loading manual suggests a maximum load of 5.8gr of TB with a 250gr lead bullet. From past experience with TB, I started out at 6.0gr. and loaded up 10 of them. Then 10 with 6.5gr, 6.9gr, 7.2gr, 7.4gr, and 7.5gr. Five shots were fired from one gun and five from the other gun. They do not impact at exactly the same place, but are very close.
The first 10 shots (with 6.0gr) did not seal the chamber. There was severe blowback (soot) along the front of the cases. The accuracy was poor, too. The group was fairly round, though. Next up was 6.5gr. It did not seal the chamber either, but the soot at the front of the cases was less. Accuracy was still poor. Then I went to 6.9gr. That load pretty much sealed the chamber with only a small amount of soot remaining. Accuracy was still poor, but just slightly better.
Then I moved to 7.2gr. The chambers sealed with that load and the accuracy was considerably better (about half the size of the previous three loads). I can live with that. 7.4 was up next. The chambers stayed sealed and the accuracy was just slightly worse than the 7.2gr load (maybe 60% of the size of the first three loads). The 7.5gr load was a repeat of 7.4gr. Interestingly, the 7.5gr load did not fill the case to the base of the seated bullet. Recoil was mild with all loads. There were no signs of excessive pressure on anything (case, primer, ejection, etc).
I measured the hardness of the Berry's bullets, first with the copper in place (Bhn 16-17). Then I filed off the copper and remeasured it (Bhn 11-12). I am thinking that the plating makes the bullet too hard for Trail Boss. When I am able to get a proper mould, I will cast up some bullets at Bhn 9 to 11 and try them. I am still concerned that anything under 7.2gr will not seal the chamber, at least with Starline cases. For the Berry bullets, I intend to try a bunch more from 7.5gr to 8.0gr. Somewhere around 7.8gr to 8.0gr, the case should be full without compression. I don't intend to try it with any compression.
Interestingly, the center of the groups did not move much from 6.0gr to 7.5gr. Slightly higher with heavier loads is all. All the groups are all a little low and to the left, which can be adjusted with a file when I have decided on a load. I have not measured the speed of any of these yet. When I get an accurate load I will check it.