Originally Posted by
MountainDevil54
230gr XTP & 60 grains of powder? Now who's being unethical
Not me. Now, bear in mind, while we may question the velocity vs charge weights that a manual publishes, the velocity loss is subject only to the science of ballistics. Data obtained is measurable and repeatable.
Lyman's data on page 260 of the Black Powder Handbook, 2nd edition, shows 120 Gr of FFg propelling a .535, 230 Gr roundball to 1803 FPS. Remaining velocity at 100 yards is 1093, and the energy is 610 ftlbs. On page 237, 60 Gr of FFFg gives 1435 FPS. Here's where we stop and substitute our XTP. Hornady says the BC is .188. So, I took the data from and old Speer #11 for a .190 BC, on page 520. Starting at 1400 FPS, remaining velocity at 100 Yards is 1149, and the energy is 673, about 10% higher than the roundball. Actually, both the velocity and energy would be higher still, due to the extra 35 FPS over our 1400 FPS data. However, no need to get that precise. The XTP is better at 100 yards than the roundball, with half the powder.
According to Hornady's data, the expansion range of the XTP is 600-1650, so the middle of that range is 1125. Our 230 XTP load is just slightly above that at 100 yards, and does not exceed the velocity expansion range even at the muzzle. A little Googling show that people who have used this bullet seem to really like it.
What part of this strikes you as unethical?
Old Bob