I got a chance to take the new .459 bullets to the range. The finished weight was 710-712 grains loaded with 32, 34 grains h4198 and 42, 44 IMR 3031 seated to 3.020 (max length in BFR cylinder) They did surprisingly well. The velocity of the h4198 loads was in the 1360-1380 FPS range chronograph was 15ft away. Recoil was less than other loads I have shot in it. The 3031 loads produced slightly lower velocities (1320 ish) and much more recoil. These heavy bullets really highlight what powder charge can do to felt recoil.
These results may be due to the fact that my chronograph is a cheap Caldwell, but the readings were consistent. Guess that means I'll have to try a few more times.
There is also room for improvement. The 34 grain loads showed flattening primer, but very little case head expansion. I'll be on the lookout for RL7 and maybe Accurate 5744. They are slightly faster and may be able to produce a little extra speed in the relatively short 10in barrel. (short for the 45/70).
These results do prove a few things though.
1. I did not use a heavy roll crimp on these rounds. Only the mouth of the case was expanded using a 45acp expander, and these bullets sit a way back in the case so there is a lot of neck tension. I used the resize die to make a taper crimp. I would rather use a roll crimp, but I wanted to use up the whole cylinder, and the none of the grooves lined up with the case mouth. None of the bullets jumped and with the bullets seated as far out as they were, a couple thousandths jump would have locked up the cylinder. Neck tension does much more to keep the bullet in place than a roll crimp.
2. If you have or are considering a BFR get new grips. The factory grips are actually Uncle Mikes Super Blackhawk Grips. They suck. The only time I shot heavy loads with the factory grips my palm hurt for two days. SBH grips do not fit the BFRs well like some people claim. The grips I have now are Hogue Pau Ferro monogrips that are BFR specific. You can also have the grip frame reshaped to the Bisley frame with wood grips. It is worth it.
3. Smith and Wesson X-Frame owners can suck it. The 500s can only push a 700 up to just over 1000, not even enough to stabilize. No offense if you have an X-Frame, but they seem to be magnets for douche bags that have now concept of bullet energy, and think the 500 is the most powerful revolver in the world because the brochure said so. You may recall the video of the 50-90 BFR from the bullet molds thread. Some idiot in the comments posted, "I'd like to see how he handles the 500 s&w". That 50-90 can make double the energy and at least three times the recoil with max loads. Even my little 45/70 can outpace those silly paper weights. A 500 S&W BFR should be able to duplicate these results, but the smitty can suck it.
These results may be due to the fact that my chronograph is a cheap Caldwell, but the readings were consistent. Guess that means I'll have to try a few more times.

These results do prove a few things though.
1. I did not use a heavy roll crimp on these rounds. Only the mouth of the case was expanded using a 45acp expander, and these bullets sit a way back in the case so there is a lot of neck tension. I used the resize die to make a taper crimp. I would rather use a roll crimp, but I wanted to use up the whole cylinder, and the none of the grooves lined up with the case mouth. None of the bullets jumped and with the bullets seated as far out as they were, a couple thousandths jump would have locked up the cylinder. Neck tension does much more to keep the bullet in place than a roll crimp.
2. If you have or are considering a BFR get new grips. The factory grips are actually Uncle Mikes Super Blackhawk Grips. They suck. The only time I shot heavy loads with the factory grips my palm hurt for two days. SBH grips do not fit the BFRs well like some people claim. The grips I have now are Hogue Pau Ferro monogrips that are BFR specific. You can also have the grip frame reshaped to the Bisley frame with wood grips. It is worth it.
3. Smith and Wesson X-Frame owners can suck it. The 500s can only push a 700 up to just over 1000, not even enough to stabilize. No offense if you have an X-Frame, but they seem to be magnets for douche bags that have now concept of bullet energy, and think the 500 is the most powerful revolver in the world because the brochure said so. You may recall the video of the 50-90 BFR from the bullet molds thread. Some idiot in the comments posted, "I'd like to see how he handles the 500 s&w". That 50-90 can make double the energy and at least three times the recoil with max loads. Even my little 45/70 can outpace those silly paper weights. A 500 S&W BFR should be able to duplicate these results, but the smitty can suck it.
