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2f vs 3f

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Well the stock answer is of course that the smaller grain will burn faster generating more pressure for a given amount of powder.... Assuming equal volume and or weight.

I have personally put plenty of 2f and 3F through an 1858. I don't have a chronograph but to my untrained eye it seems they're both moving out of that muzzle pretty good. My chronograph is shooting at various distances right at the edge of water where it meets a large embankment so all rounds will 100% impact that mound of Earth.

Not an exact chronograph but it gives you a little idea of how fast it's moving
 
Well the stock answer is of course that the smaller grain will burn faster generating more pressure for a given amount of powder.... Assuming equal volume and or weight.

I have personally put plenty of 2f and 3F through an 1858. I don't have a chronograph but to my untrained eye it seems they're both moving out of that muzzle pretty good. My chronograph is shooting at various distances right at the edge of water where it meets a large embankment so all rounds will 100% impact that mound of Earth.

Not an exact chronograph but it gives you a little idea of how fast it's moving
Thank you. That’s the kind of info I was looking for.
Have you noticed that either had a flatter trajectory?
Does the slower burn of 3f burn more completely?
Using 3f in my TC Hawken 45cal it seems that I have unburnt powder residue after the shot.
 
Thank you. That’s the kind of info I was looking for.
Have you noticed that either had a flatter trajectory?
Does the slower burn of 3f burn more completely?
Using 3f in my TC Hawken 45cal it seems that I have unburnt powder residue after the shot.
Usually 3f burns more completely and leaves less fouling, and shouldn't be leaving unburnt powder.
Producing more pressure (thus more velocity) if the same charge is used as 2f is why it is recommended to reduce one's powder charge when developing a new load using finer powder.
Part of the reason I use 3f in everything is being able to match 2f performance with less powder. However, I do notice a little bit more/sharper recoil.
 
I find 3F to produces less or smaller fouling and can shoot 20 to 30 shots without swabbing. With 2F after about 10 shots it gets hard to load.
 
Thank you. That’s the kind of info I was looking for.
Have you noticed that either had a flatter trajectory?
Does the slower burn of 3f burn more completely?
Using 3f in my TC Hawken 45cal it seems that I have unburnt powder residue after the shot.
I can't really tell but I'm only shooting revolvers at relatively short distance. I think what others have added here is accurate information.
 
The difference is the 3f has more surface area exposed to ignition than 2f
The 2F kernels are bigger, so that is more surface area. Additionally, the 3F would be packed tighter (more smaller particles in same sized space) so there would be less exposed surface area.

My analogy would be wood sticks. The smaller wood lights easier and burns quicker. Your 1/4 inch kindling lights easier and burns quicker than your 1-inch starter wood. If you held a fist-full of the 1/4-inch you can get one lit and it will light the others in your hand quicker than the same with a handful of 1-inch sticks. Likewise, the smaller 3F kernel can light and burn through quicker than the larger 2F kernel. Subsequently, each 3F kernel is lit in succession faster than bigger 2F kernels. While in the barrel, the whole thing starts moving while some is still burning because gas from the first little bit to ignite expands. That explains in part why 3F produces a little more pressure in the barrel and may create more velocity that a bigger powder granule up to a point.

If the barrel is long enough for the amount of powder to completely ignite and for the full amount of combustion gas to get behind it, there is a chance the velocity is the same between 3F and 2F. But with shorter barrels, the 3F has a little more gas behind it sooner since it burned faster, so the result is more velocity than the same amount of 2F. I think velocity is equated to flatter trajectory. The faster something gets where you want it to go, the less drop because it is effected by gravity, wind and resistance for a shorter period of time (but the same distance). There is one exception. Some very heavy projectiles moving slowly will push the stock down and barrel up as a motion in response to recoil. Since the barrel is rising slowly, the projectile goes up from the line of sight at a greater arc then a faster, projectile that exited the barrel quicker, before the recoil lifted the barrel much.

For a real answer, you need a chronograph and the patience to keep shooting loads as alike as you can get them, under the same exact circumstances.

That's what I think. I am not a know-it-all, even though my post kinda sounds like I am.
 
The 2F kernels are bigger, so that is more surface area. Additionally, the 3F would be packed tighter (more smaller particles in same sized space) so there would be less exposed surface area.

My analogy would be wood sticks. The smaller wood lights easier and burns quicker. Your 1/4 inch kindling lights easier and burns quicker than your 1-inch starter wood. If you held a fist-full of the 1/4-inch you can get one lit and it will light the others in your hand quicker than the same with a handful of 1-inch sticks. Likewise, the smaller 3F kernel can light and burn through quicker than the larger 2F kernel. Subsequently, each 3F kernel is lit in succession faster than bigger 2F kernels. While in the barrel, the whole thing starts moving while some is still burning because gas from the first little bit to ignite expands. That explains in part why 3F produces a little more pressure in the barrel and may create more velocity that a bigger powder granule up to a point.

If the barrel is long enough for the amount of powder to completely ignite and for the full amount of combustion gas to get behind it, there is a chance the velocity is the same between 3F and 2F. But with shorter barrels, the 3F has a little more gas behind it sooner since it burned faster, so the result is more velocity than the same amount of 2F. I think velocity is equated to flatter trajectory. The faster something gets where you want it to go, the less drop because it is effected by gravity, wind and resistance for a shorter period of time (but the same distance). There is one exception. Some very heavy projectiles moving slowly will push the stock down and barrel up as a motion in response to recoil. Since the barrel is rising slowly, the projectile goes up from the line of sight at a greater arc then a faster, projectile that exited the barrel quicker, before the recoil lifted the barrel much.

For a real answer, you need a chronograph and the patience to keep shooting loads as alike as you can get them, under the same exact circumstances.

That's what I think. I am not a know-it-all, even though my post kinda sounds like I am.
Very informative. Thank you.
 
I have found 3f works very well in muzzle loading shotguns. At Friendship in trap matches using a single barrel, in-line trap gun with a modern Remington converted barrel one can shoot matches nearly all day with 3f. It seems to burn a bit cleaner than 2f for such use in trap.
 
The 2F kernels are larger than a 3F kernel, so the 2F kernel will have more surface area. But, being smaller, there will be a lot more surface area for the 3F kernels as there will be a lot more of them in a given volume of powder. Sure, the smaller kernels will be packed tighter, but there is plenty of room for the heat to get to. The potassium nitrate of the powder provides the oxygen for the burning of the powder, not the air. The heat releases the oxygen in the potassium nitrate and the 3F burns faster than the 2F.
 
I noticed that your question is "for the same weight of 2f and 3f" which indicates that you know that typical black powder measurers in the field use volume, not weight. In my history I had access to a friend's loading room for high power cartridge rifles, equipped with accurate scales and a device that could trickle in a grain or two of powder. With that equipment you could make equal loads for comparison.

Here is an idea for an unproven method of determining whether 2f or 3f provides flatter trajectory. Use a three hole punch on the sides of one edge of paper "targets" simultaneously. Set up the paper "targets" at measured distances, say 25, 50, 75 and 100 yards, all in line using a laser through the holes. Be certain that the laser beam is level. Bench rest your muzzleloader and as best as you can, aim the sights parallel with the laser beam. Fire your test shots, recording your load data. In theory, the trajectory will arc up at first, reach the top of the arc, then drop more rapidly than the ascent. But regardless, if using 3f provides a flatter trajectory than 2f, you will have the answer to your question.

Understand that this is my idea, but I've never done it. If you do I'd like to know your test results.
 
The 2F kernels are bigger, so that is more surface area. Additionally, the 3F would be packed tighter (more smaller particles in same sized space) so there would be less exposed surface area.

My analogy would be wood sticks. The smaller wood lights easier and burns quicker. Your 1/4 inch kindling lights easier and burns quicker than your 1-inch starter wood. If you held a fist-full of the 1/4-inch you can get one lit and it will light the others in your hand quicker than the same with a handful of 1-inch sticks. Likewise, the smaller 3F kernel can light and burn through quicker than the larger 2F kernel. Subsequently, each 3F kernel is lit in succession faster than bigger 2F kernels. While in the barrel, the whole thing starts moving while some is still burning because gas from the first little bit to ignite expands. That explains in part why 3F produces a little more pressure in the barrel and may create more velocity that a bigger powder granule up to a point.

If the barrel is long enough for the amount of powder to completely ignite and for the full amount of combustion gas to get behind it, there is a chance the velocity is the same between 3F and 2F. But with shorter barrels, the 3F has a little more gas behind it sooner since it burned faster, so the result is more velocity than the same amount of 2F. I think velocity is equated to flatter trajectory. The faster something gets where you want it to go, the less drop because it is effected by gravity, wind and resistance for a shorter period of time (but the same distance). There is one exception. Some very heavy projectiles moving slowly will push the stock down and barrel up as a motion in response to recoil. Since the barrel is rising slowly, the projectile goes up from the line of sight at a greater arc then a faster, projectile that exited the barrel quicker, before the recoil lifted the barrel much.

For a real answer, you need a chronograph and the patience to keep shooting loads as alike as you can get them, under the same exact circumstances.

That's what I think. I am not a know-it-all, even though my post kinda sounds like I am.
You got that backwards
 
Check out Mike Bellingers production on duelist den (you tube). He does a good job on the differences in loads of 3f and 2f. I found it interesting that after about 90 grains, velocity is actually improve with 2f over 3f, and he has a good explanation why.
 
3F, most likely. With a patched ball it may not amount to that much more but 3f is faster burning and slightly cleaner. It'll depend a lot on the powder too. T7 fffg will burn hotter than true blacks and thus move things a bit faster than fffg black.
 
I usually buy equal amounts of 2Fg and 3Fg. Sometimes it seems that I get better accuracy with 3Fg and sometimes it seems that the 2Fg works better. And sometimes it seems that the only thing I can hit is the dirt backstop. All I know is that I use both and have fun doing it.
 
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