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THEN CLICK ON Muzzle Loading Accuracy Secrets
Loads - When poor muzzleloader accuracy is due to your load, it can most often be blamed on a magnum (150 grain) powder charge. A look at the names of the most match-accurate black powder rifle cartridges in history will give you a hint: 45-70, 45-90, 45-110, etc... The first number is 45 caliber, the second is the powder charge. They never went higher than 45-120... or 120 grains of black powder! For further confirmation, ask among experienced muzzleloader shooters and they will usually say your best accuracy comes from loads between 80-120 grains of black powder, Pyrodex®, Triple Seven, or other black powder substitutes.
Another accuracy consideration is the over blast and fouling from the 209X50 primers used by so many modern muzzle loaders. We recommend adapting to small rifle primers... Either with a 25 ACP Breech Plug or the new Variflame small rifle primer system- - Click Here for Info.
Magnum 150 grain powder charges are supposed to give you a harder hitting, flatter trajectory for long range shooting, right? Well first of all, long range shooting requires ACCURACY. If the magnum load isn't accurate, the flatter trajectory isn't going to help. Second, the magnum load only gives 100-250 fps more velocity so its not a dramatically flatter trajectory anyway. And finally, the US Cavalry was knocking over Volkswagen sized buffalo with 45-70... only 70 grains of powder. You don't need 150 grains to hit hard.
Here's the truth about shooting flatter trajectories: Smaller diameter, longer bullets have higher ballistic coefficients and shoot flatter trajectories. In 50 caliber muzzle loaders, this can be achieved by using sabots and 45 caliber bullets. For example, consider the Hornady 250 grain 45 caliber SST bullet. Seated in a 50 caliber sabot and loaded over 90 grains of Pyrodex RS powder, it shoots approximately 1623 fps. Zeroed for 150 yards, it is about 4 inches high at 100 yds and 10 inches low at 200 yds. The load itself is an absolute one-hole tack-driver out of a TC Encore, and shoots with manage-able recoil... A 200 yard muzzleloader without a magnum load.
Velocity BC 50yds 100yds 150yds 200yds
1623 fps .210 +3.29" +4" 0.0" -9.87"
For deer, aim center chest out to 150yds, slight hold-over out to 200
Here's the truth about knock-down and penetration: With muzzleloaders, you increase knockdown and penetration by going with a heavier and/or harder bullet. The powder charges that produce accuracy are still between 80-120 grains but, the heavier bullet carries more momentum into the target. Hornady has saboted bullets up 300 grains. Thompson Center has soft, expanding lead Maxi-Hunter bullets up to 470 grains and hard, deep penetrating lead Maxi-Ball bullets up to 460 grains in weight. How much you need depends on the size and toughness of your game animal.
Bullet Recommendations: The relatively lightweight 250 gr. SST Sabot 200 yard load listed above broke through rib bones, lungs and exited breaking more rib bones of a 150 lb. whitetail doe at 80 yards last fall. I highly recommend that load. If your local hunting regulations don't allow sabots, I would recommend the Thompson Center 350 gr. Maxi-Hunter lead bullet for Deer and their 460 gr. Maxi-Ball lead bullet for Elk or Bear.
Powder Recommendations: I use and recommend Pyrodex® RS granular powder. If you use the new Triple 7 powder, remember it's a little faster than Pyrodex so work your loads up from a lower starting point. I believe granular powder gives me more flexibility and reliability than pellets.
HOPE THIS HELPS.