A lot of new shooters think that their best groups come with heavy powder charges. They have the targets to " Prove it". What they don't understand is that most of the shooter errors are caused by the shooter, NOT THE GUN or the load used.
Years ago, my father was shooting a revolver in .357 Magnum, using target .38 spl ammo. He shot okay at the 25 yard range, but when he put some of the hot .357 Magnum loads in the gun, his groups shrank dramatically.
He was NOT a better shot shooting the heavy loads. They just got the bullets out of the barrel faster than the target ammo did, before his shaking hands moved the barrel enough to open the groups up. He learned that over the years as he shot that gun, with both mid-range wadcutters, and with the magnum loads.
I learned much the same "lesson" with various rifles, including MLers I have shot. more powder simply pushes the ball out of the barrel faster, and you SEEM to be a better shot, or have a more " accurate load", when that is not the case. If you bench rest the gun for the loads, and eliminate as much of the human error as possible, even by having someone else shoot your gun. I found, for instance, that at longer ranges the Bullseye, no matter how " big ", seemed smaller when looking through my open sights, than the bullseye at 25 yards. I shot better groups at the longer ranges ONLY because I was forced to concentrate more on my front sight and sight picture with the longer ranged targets, than at the " easier-to-see" 25 yd. bulls.
There also can be one other thing going on INSIDE your barrel with heavy powder charges: Heavy charges jolt the PRB more, causing it to upset quicker, and expand faster and wider, sealing the bore better to keep the gases behind the PRB, compared to what happens with lighter loads. I found this phenomena disappears when OP vegetable Fiber wads are used behind the PRB, to take over the job of sealing the bore. You also will see this difference when comparing commercial, Swaged RBs, made of lead with antimony in it, to cast RBs made of pure lead. The cast balls prove to be more accurate with the lighter loads, but also shoot tighter groups with hunting charges. The only reason this occurs is because the commercial, harder lead alloy balls do not expand as quickly or as much as do the cast balls, when the gun is fired.
When I was at the Sgt. York Memorial Chunk Gun Shooting Match this past March, virtually all the shooters were using cast RBs- NOT the swaged commercial balls. That in itself is a fairly good recommendation for using Cast lead balls for these guns, when you are looking for best accuracy. :hmm: :thumbsup:
