in my 54 i use 80 grains of 3F for RB and 110 of 3F for conical . the twist in the barrel is 1 in 70 .
as to the differences in 2F and 3F .
2F is a slower burn because its bigger in grain .
Now keep in mind this all happens in milla seconds . But basically what happens is it takes longer for the 2F grain “ when compared to 3F” to completely combust . This allow the projectile to be moved down the bore some before the entire charge is ignited . Thus you barrel pressures are lower then would be found with a comparable load of 3F..
But if your using 3F , simply reducing the charge by 10 to 15 grains “depending on powder maker “ will normally bring 3F down to comparable pressures of 2F . Notice I didn’t say exsact , just comparable .
However what will not change is the area where the pressure spike takes place . 3F being a faster burn , it produces a steeper spike then 2F and thus spikes sooner in the barrel
Again remember this is milliseconds , but it does play an effect on the end result .
Now one of the differences in powder manufactures is the charcoal they use. Different charcoals produce different burn rates . Which again results in different barrel pressures . thus giving different muzzle velocities for like loads . Swiss is hotter the Goex and as such the charge can be reduced when comparing the two , so as to bring the Swiss into the Pressure range that you get when using Goex . Thus lb for Lb. you can actually use less Swiss to get the same results as a lb of Goex .
Again myself I have found this reduction to be in the 10 to 15 grain range .
See its really a game of pressures . At what pressure range does my rifle throw the best and most consistent pattern
Now SSE ask if there is a lighter load in which accuracy will improve again . Well in theory the answer would be yes. That yes " in theory" is true for both a lower and a higher charge .
See pressure in a barrel creates what’s called harmonics. IE barrel harmonics .
As a charge goes off , the barrel for lack of a better description , vibrates . This vibration is like sound waves . The trick is to find the pressure that produces a wave that comes to the end of the barrel and ends at the same point on the wave as with a heavier or lighter charge ..
Now your point of aim will change but the barrels ability to throw the ball to the same tight area in theory should stay relatively the same .
Now again this can change from barrel to barrel because there are so many variables in play . like what the barrel is made from . the effects of diffrent types of rifling as well as barrel thickness .
But basically I find the this wave is very close to being divisible or multiplied by 2 for a starting point for finding that harmonics .
So say for a barrel that likes 90 grains . One could very well find that a lower charge in the 45 grain area will bring back you accuracy .
The opposite also holds true . in theory if your group starts opening back up when you go above 90 grains , that group would then come back into harmonics at a higher charge .
Now im not saying or recommending folks go out and load 180 grains of powder to test this .
NO that’s not the case at all .
Again what your looking at is pressures . BP doesn’t produce a set given pressure that’s multipliable .
IE 20 grains of 3F does NOT produce 2X the pressure as 10 grains .
BUT if one takes the time to figure out barrel pressures you can then start to learn barrel harmonics and how they relate to those pressures and then calculate the harmonic waves that will hold accuracy .
Did I totally confuse you all LOL
Topic: shooting the Browning 54 muzzleloader (Read 1507 times)