Pappy: The PR Duplex bullets are a lead 35 caliber bullet in an orange 45 caliber sabot inside a 50 caliber sabot. While made by MMC the injection molds are property of Precision Rifle . Because they are proprietary you can only buy them from Precision Rifle. The orange 35 caliber sabot is specially molded with a base that fits inside the rounded cavity in the inside bottom of the 50 caliber sabot. I have bought other 35 caliber MMC sabots and cut the base off so they fit inside the 50 caliber sabot and accuracy was abysmal.
Cecil Epps claims a Ballistic Coefficient of .375 for his 35 caliber lead bullet. No other 35 caliber bullet that I know of comes even close to that BC. I even used the charts that P. O. Ackley included with his book long before chronographs and computers to get a BC estimate and it was no where near .375. I called Epps to discuss all these matters with him and he went completely ballistic (no pun intended) on me. After looking at Epp's ballistic charts he states the charts were developed on Jan. 12, 2003 in Canada at a temperature of minus 32 degrees C. If he used 2 chronos (one at the muzzle and one at the target) and used the time of flight to calculate a BC that might explain his unusual high BC.
I have replaced the PR 50 caliber sabot with a Harvester crushed rib for the second shot because the factory PR bullets are so hard to load. The accuracy deteriorated but they loaded a lot quicker. The hard loading indicates to me that the plastic formula is much harder than other sabots. The reason I put so much effort into this system is trajectory. High Performance Muzzleloading did a trajectory comparison of the drop for a projectile sighted in at 100 yards. The drop at 200 yards was 5.25" for the 195 grain duplex Pr bullet and the Hornady 250 grain SST bullet was 10.8".
