mayguy wrote:

I did try one heavy bullet, 375gr. Buffalo Bullet, this is just what I think I remember about the vel.---- 110grs. BM3, about 1900fps out of my Omega.

Wow! That is right in-line with the website's claims. Almost 3000 ft-lbs at the muzzle. To be honest, I thought they were joshing. It doesn't seem so expensive now. A guy can use lesser charges and still get the velocities of their old "dirtier" substitutes, for not too much extra money. OR get the performance you just posted which isn't possible with the others.

A note of caution. I compared their 45-70 load with other loads at hodgdon's website. I was amazed to find that BM3 is producing results I though were comparable to Varget. For example, 50 grains (by weight)Varget propelled a 405 grain bullet to 1718 fps at CUP 20,900 and energy of 2630 ft-lbs. 65 grains of BM3 (by weight) propells a 435 grain bullet to 1864 fps and energy of 3325 ft-lbs. The BM3 load has 26% more energy using 30% more powder. These two powders are similar in their performance, not exact mind you, but Magkor doesn't publish pressures and Im doing the best I can here.

If i were a betting man, I would guess the BM3 45-70 load several thousand psi above the lighter Varget load. Well above 21,000 anyway. The BlackMag site suggests the powder works well in .45 and .50 caliber rifles with 400+ grain projectiles with charges of 100 to 120 grains[]by volume. DON'T DO THAT IN .45 CAL. UNTIL MORE IS KNOWN.

Being BM3 is of the same class of powder as pinnacle, I made a make shift calculation using hpmuzzling.com's conversion table to calculate the volume of the charge inmagkor's 45-70 load. The answer? Approximately 80 grains by Volume. The heaviest muzzleloading bullets for 45 cal. i know of are 360 grains. But if I were asked to guess the pressure of 80 grains (volume) of BM3 and a 360 grain projectile in a .45 caliber muzzleloader I would suggest over 22,000 psi. I don't know how much over. But only GODknows how high the pressure would go if one would put 120 grains of BM3 and a 360 grain conical in a .45 caliber muzzleloader.

I emailed the Magkor folks a couple of weeks ago about the excerpt below which is in their FAQ:

The above is just an example. We have found that Black Mag’3® also yields exceptional performance with powder charges from 100 to 120-grain in rifles of .45 to .50 calibers. In fact, because of its unique burning characteristics, charges in this range will yield higher velocities with heavy bullets in the 400 grain range.

I told them my concerns. I received an email saying that my concerns were being forwarded to another department and would be contacted later. I've not heard from them yet.

Just wanted to caution against high volume load in .45 cal. until more is known.

Happy Hunting, Phil