Unburned powder...or just fouling on the snow?

[roundball]

I see posts from time to time saying that excess powder that is not burned simply falls to the ground, do it over snow and you'll see the black specs, etc, etc.

I would think that a few kernels of unburned powder would be consumed in the muzzle flash...and IMO, what hits the ground is just black specs of fouling, not specs of unburned powder.

Take a shot after dark and see the muzzle flash that's 3 feet long and a foot wide...how does unburned kernels of powder survive that when BP normally ignites just from the infrared pulse of a comparatively weak pan flash in the first place?

Inquiring minds want to know......

 

[Mike Brooks]

I agree with your thoughts. Seems an impossibility for any powder not to be consumed either in the barrel or after it leaves the muzzle.

 

[ewan]

so is the most efficient load one that shows no burning kernels exiting the bore - all are burnt just as the ball exits the barrel.?? hmm hmm i wonder :hmm:

i wonder what the difference on target would be between someones best target load and a load that showed no kernels.. :hmm:

 

[Black Hand]

Probably along the same lines that you can put out a fire with gasoline if you pour in on a small fire. Or how structures survive at "ground zero" of an explosion. Not all of your powder will be burned if it is protected by the patch, lube, other powder, moving too fast to ingnite, etc. Just my take on this thought........

 

[Lone Carabiner]

Paul Vallandingham had a post on the formula for calculating max charge of powder, I had found out years ago that heavy charges throw a lot of burning powder out the muzzle. Maybe the unburnt powder is 'out running the fire' so to speak.

 

[2172]

RB....I seem to remember this as one of those things I learned from reading when I was first interested in M-L, and no one I knew, knew anything..I believed it at the time..today, I think it is one of those theories that are put forward by the armchair experts and which do not no survive an actual test...if any unburned powder does survive the shot, I suspect it'd stll be a lousy way to calculate a max load...Hank

 

[gmww]

Hiya Roundball. You might be interested to know that Sam Fadala mentions the concept of shooting a BP over snow. It is on Page 96 of the Lyman Black Powder handbook & Loading Manual. It's in the Chapter titled Black Powder Fact and Fancy.

Here is what's written.

"Shooting over snow to find a good load.

FALSE- The idea itself wasnt too far-fetched. Oldtime shooters knew that there was a considerable left over black powder after firing their guns, so they reasoned that a good load would be one that consumed the charge, leaving very little unburned powder behind. Shooting over snow would let them know when they reached that ideal charge, telltale flecks of powder showing up on the clean white surface of the snow. Couldn't happen, however because black powder in any amount leaves about half of itself behind."

:hatsoff:

Edit: I've heard it both ways Roundball. I've been told it's unburnt powder and of course that it's just fouling. Paul wrote that it had been his experience that it was unburnt powder. Seems to me either way, the longer the barrel the more residue is going to be captured. OOPS that was for the 1:48" thread. :rotf:

 

Perhaps you could shoot over a clean white sheet then gather the black flecks that land on it and see if they flare when presented a match??

Cody

 

[walley]

May be lack of oxygen in the bore during the
inital blast, due to the density of the powders.
Might try 2F vs 3F and see which burns more
efficiently with equal loads.

Just a thought.

 

[paulvallandigham]

The forumla is 11.5 grains per cubic inch of barrel. YOu find the cubic area by first finding the area of the diameter of the round, mulitplying that times pi, then multiplying that by the length of the barrel, and then by 11.5. For a .62 cal. Smoothbore, with a 42 inch barrel the formula works like this.( PI R Squared divided by 4) or .620 x .620= .3844 x 3.1416( pi)= 1.2076 divided by 4 = .03019.

.03019 times 11.5 = 3.47185 grains per cubic inch.

3.47185 times 42 = 145.81 Grains

145.8 is the maximum charge of powder your gun will burn in that barrel length.

May I suggest that instead of shooting the gun over snow, where you are admittedly going to collect both burned residue, and unburned powder when you exceed the maximum load, that you shoot the gun over a clean sheet, or newpaper. You can fold either up and pour the stuff on them into a small pile for examination. Then simply put a match to the pile. If it burns, what you had was unburned powder. If it doesn't, its residue. Most of us will be able to see the difference just looking at that small pile of dark ' stuff ".

I have no doubt, from my onw experiences, that part of the powder that is pushed out of the barrel, unburned burns in the powder flash. But, some of the unburned powder drops down and away from the muzzle flash to escape being burned.

Using the same formula, my .50 cal. rifle with its 389 inch barrel can shoot a max. load of 88 grains. My .62 fowler with its 30 inch barrel can shoot a max charge of 104.1 grains.

( .50 x .50 x 3.1416 divided by 4, x 11.5 x 39= 88.0 grains.)

( .620 x .620 x 3.1416, divided by 4, x 11.5 x 30 = 104.1 grains.)

If you are having trouble running the forumla, send me a PM and I will help you do it for your gun(s).

The other way of stating the formula, that works out the same, is to divide your bore diameter by 2, then multiply it by itself( square), then multiply by Pi, to get the area of the bore. Then multiply by barrel legnth to get the total area of the barrel's bore, then by 11.5 grains to get your maximum charge.

With a 62 cal fowler, .620 divided by 2( to get its radius, as in Pi R Squared) is .31. .31 x .31= .0961. .0961 times pi( 3.1416) = .3019077, or .3019. .3019 times barrel length( 30 inches) = 9.057 times 11.5 = 104.1555, or 104.1 Grains as the maximum charge that will burn in that barrel length. Roundball's .44 inch 62 ca. rifle will shoot. 152.7614 grains of powder in its length.

I personally don't want to shoot that large a powder charge and deal with the recoil it generates. I don't expect such a load would give optimum velocities or accuracy, either. He uses an 80 grain charge, I believe with a PRB, and I suspect that gives much better accuracy, and more tolerable recoil forces, based on some of the data I have read, and my own experiences clocking heavy loads on my chronograph.

Hope this helps others.

 

[Coot]

Both Paulvallandigham (on another post) and Cody have proposed a simple test - shoot over paper or a sheet, gather the black deposits & see if they ignite (=unburnt powder) or not (=fouling). It would seem that not only is unburnt powder just wasted but that some of the burnt powder could be wasted as well since the ball velocity is not going to increase once the ball leaves the barrel. Excess powder could still be burning in the barrel or in the muzzle flash after the ball leaves, which would be (IMHO) particularly likely if the vent was located foward of the center of the center of the maximum usefull charge. Will someone report on the paper/sheet results?

 

[Brutus]

Question about the formula. Using it, I've found that my GPR will burn 84 grains. From what I understand, any more than this will just be blown out the barrel, correct?

If that's true, (not saying either way) why is there a max load 120 grains for it? Wouldn't any extra powder be shot out the end before it could burn/create execess pressure? Is there something I'm missing here? :hmm:

 

[roundball]

Question about the formula. Using it, I've found that my GPR will burn 84 grains. From what I understand, any more than this will just be blown out the barrel, correct?

If that's true, (not saying either way) why is there a max load 120 grains for it? Wouldn't any extra powder be shot out the end before it could burn/create execess pressure? Is there something I'm missing here? :hmm:

No, you're not confused...chronographs also show ever increasing charge amounts produce ever higher velocities for those charges listed in a manufacturers load data chart

 

[paulvallandigham]

Are you shooting a conical or PRB? Remember, you can load more powder, but that powder also adds mass( weight) to what is being pushed out the barrel( Ball or bullet). In fact, you have to add one half to weight of your powder charge to the weight of the bullet, patch, and lube, to understand how much powder you need to reach a certain velocity at the muzzle. BP burns progressively all the way down the barrel. That is why it is still used to test barrels in proof loads.

The more powder you load, the more velocity you will get, but it will decline as you put more and more powder in over that maximum figure. So, just don't pull some velocity for a given load off a chart. Sit down with a piece of paper, or graph paper, and plot out the increases in velocity for each 5 grains of powder added to the load. Note where this maximum powder charge is located on your graph. Then you will get a better understand of why we recommend loading below this maximum for optimum performance, and why we say that loading more powder just increases the recoil.

If you really want to learn about BP velocity and what it does at distance, consult the Lyman tables regarding down range velocity and energy at say 100 yds. for light and heavy loads. You will find that whatever goes out faster, slows down faster, too. There is a point when you gain maximum evergy at 100 yds, or 150 yds., or whatever range you think your particular gun can kill a deer at, shooting a PRB, and more than that is just recoil, and contributes nothing to down range velocity, or killing energy.

 

[Lone Carabiner]

Seems to make sense Paul. Correct if I'm wrong, but the initial ignition of the charge moves the projectile a great deal down the barrel and then the space occupied by the hot gas is increasing so pressure will not increase past a certain point-say 1/2 way down the barrel? That is why a heavy charge has incomplete burn, the chamber size has increased and pressure no longer builds rapidly.
In old days BP was of uncertain formulation and early rifles were longer than moderns to get a good burn of the powder even tho it was not a really heavy charge. Old timers would love to have had Goex 3f in their muskets and full stock rifles. That is if they had sense enough to use a reduced charge to start load development.

 

[paulvallandigham]

That is petty much my understanding. That is why you see the breech end of barrels made larger, but after the half way point, they are made fairly thin. Think of the Octagon to round barrel fusils and fowlers you see.

 

[bezoar]

Technically it can be both. Wet powder dont burn, and your muzzleloader wont, i dont see how, will generate enough heat to dry and detonate that wet grain of powder SO it will just fall to the ground.

I can say that because last season we had to draw charges every few days because of moisture problems. Fully clean and dry the gun, let it adjust to the interior temp of around 70-75 degrees, load it and then take it outside and store on porch at night.
After three days, a shovel full of hot ashes just taken from the outside wood stove could not detonate pyrodex powder, or pyrodex pellets.

But you will get alot of powder blown out behind your projectile igniting in that flash. Just find someone with an inline that can handle pyrodex pellets, 150 grain max gun. Load 3 50 grain pellets and a saboted bullet, and watch fromt eh side as its fred a few times, and you will see the bullet exit the barrel followed by the pyrodex pellet directly behind it being sent downrange as an incendiary device.
I learned that form experience.

 

[renovato]

Smokeless powder does it too and it ain't fouling when you find actual flakes of powder. Since smokeless and BP both contain their own oxygen, I don't see why they don't ignite in the bore and continue to burn even outside of it. With BP I can see the powder next to the patch being wet perhaps but increased loads do blow out more unburned powder. I'll be interested in how this thread turns out.

 

[musketman]

Take a shot after dark and see the muzzle flash that's 3 feet long and a foot wide...how does unburned kernels of powder survive that when BP normally ignites just from the infrared pulse of a comparatively weak pan flash in the first place?

Inquiring minds want to know......

I suspect some of what we see in front of us is the powder that was stuck against the lubed patch or bullet, if the lube keeps the patch from burning then that same lube should keep the powder that's against it from burning too when it's absorbed into the granules...

Again, this is just speculation and I never took the time to gather them up and see if they'll ignite after they were dried, so I'll just chalk this up to: "In My Opinion" for now...

 

[paulvallandigham]

When I first got my .50 cal. rifle, I needed to know the maximum charge it would handle. The books were full of loads, and data, for various lengths of barrels. I first had worked up a load of 65 grains for target work, starting at 50 grains( caliber equivalent, based on what someone suggested), and then went up 5 grain to 75 grains, and compared targets. That work was done at 25yds, and 50 yds. Then I wanted a stouter load, I thought, for hunting. I put newspaper down on the grown, weighed wieht rocks and bricks so it didn't blow away, and first fired a shot with my 65 grain charge over the paper. Only a few clinkers, but no unburned powder was recovered. I then arbitrarily picked a charge of 100 grains of FFg, with my .490 PRB, and fired it over the paper. Like Roundball, my experience firing heavy loads at night, and watching others fire them was to see that long streak of flame coming out the barrel about Three Feet!! I was doubting that even 100 grains would leave any unburned powder. But, I fired the gun anyway. When my friend helped me careful lift up that newspaper, and we poured the contents onto the back of a paper target, sure enough, you could see unburned powder! I would have lost money if I had been a betting man. We forgot to bring a scale( a reflection of my serious doubts about their being any unburned powder) so I was not able to weigh the unburned powder. It was not much- probably only a few grains in weight. But, I was still in disbelief, and that is why we put a light to it. DAMN! It did burn! I had to admit to my buddy that I was all wrong. He took particular glee in finding out that I was wrong, although he had no idea if we would find unburned powder, either. I have since fired blanks off into the night, and everytime I see that long flame, and a few falling sparks, or embers of residue, or burning powder, I think of that test.

My back does not let me bend over like I used to be able to, anymore, so I have not repeated the test. I probably should. And, if I do, I can assure you I will take my powder scale with me, to weigh the unburned powder I find. And, I will pick out all the clinkers with a magnifying glass and tweezers, so I don't queer the weight, either!

Only recently did an engineering friend give me that formula that I posted above. I found out that the maximum powder charge I can burn in my 39 inch barrel is 88 grains. Not much less, really, than tht 100 grain charge that left some residual unburned powder on the paper. I am wondering how much more powder I might be able to burn by using Walter's fiber wads, and fillers under that PRB? And, this time, I will use my chronograph to also determine any useful increase in velocity! Now, If I can just rope some innocent bystander into putting that paper down, and picking it up for me..... :hmm: