Is excess powder really blown out?

[Carbon 6]

Thanks Robin.

 

[Stumpkiller]

But, ha ha, there is also the weight of the powder (both burning, unburnt and ash) that is moving along with the ball. I guarantee if you set the rifle on a smooth flat surface (ideally a frictionless one) and touch it off with a fuse it will move more than 0.2" in a direction opposite the ball's travel. ;-)

 

[shdwlkr]

I know I am late to the party on this thread, but have been thinking about this question a lot. Now if you start the fire at the base of the powder charge and things start moving down the barrel pushing the ball and patch if all the powder is not consumed what must happen to it? From my feeble understanding of such things there must be unburned powder ejected out the muzzle. So the best idea would be to keep the charge at such a level that all powder is consumed in the time it travels down the bore or have I missed something?

 

[Rifleman1776]

my own hand built .45 cal. flintlock rifle with a Douglas "1 in 48 twist," 39 inch long barrel. My "target load" where it shot the smallest group size for shooting paper or other targets at 25 and 50 yards was 42 1/2 grains of Dupont FFFg.

It has been so long since I measured twist in a Douglas barrel, I admit my memory might be off. But, I do believe Douglas barrels are 1:66" twist. I have three in the safe, will have to re-measure them to find out fer certain, fer sure. But, two are .45s and like a tight ball/patch combo for best accuracy with 45-55 gr. of 3Fg. The other is a .40" cal. that hasn't been shot enough to know anything about it's likes and dislikes. I have to chuckle at your 1/2 gr. measure of bp. Methinks yer rifle would not know the difference between 42, 42 1/2, 43, 43 1/2 gr. charges. Bp isn't that fussy. I know, I know, don't say that to serious bench rest or slug gun shooters. Some of them OCD guys will count granules to get the same perzact charge for every shot. I find it usually takes a 5 gr. change in charge to affect performance. But, that's just MHO.

 

[Artificer]

Normally I would agree that a half grain change would not do much in a BP rifle, but that rifle was the single exception I ever ran across in all the years I've been doing this, including at two World International Muzzleloading Championships.

Yes, I fully admit without reservation I am in a small bunch that tries to get the very best group size possible for target shooting (or other types of shooting), no matter what shooting discipline I've been involved with over the years. This because such things count in National and International Competition and in other uses outside this forum.

Gus

 

[Spike]

garryd

powder is FF, Bullet Wt 245 Gr, 28” BBl distance to Chronograph about 10’

100 Gr Powder AP Goex RS 777
Velocity 1498 1647 1850 1961
recoil 9.4 10.3 11.6 12.3

150 Gr Powder
Velocity 1789 1839 2139 2166
recoil Ft# 13.3 14.3 16 16.2
recoil is a fairly complicated formula using the velocity, bullet wt, powder wt, gun wt
I used a ballistics program to calculate the recoil but your shoulder can sure tell the difference

 

[Carbon 6]

I'm going to revert to something I said way back at the beginning.

Unburnt powder or unburnable powder ? .

If any powder makes it out the end of the barrel and onto the ground escaping all that heat, flame, and pressure, we have to categorize it as burnt or unburnable.

 

[Dr5x]

AS FAR AS UNBURNED EXCESS POWDER BLOWING OUT AND STILL BEING COLLECTABLE AND REUSABLE SEEMS UNLIKELY TO ME/
THERE IS MUCH THAT GOES ON WHEN A EIFLE IS FIRED THAT WE DO NOT SEE DURING DAYLIGHT HOURS.
FIRING A MUZZLWLOADER AFTER SUNDOWN WILL SHOW YOU A STREAM OF FLAMES THAT EXIT THE BARREL FOR SOME FEET WHICH EXTENDS AS MUCH AS 5 FEET THAT, I WOULD IMAGINE WOULD ENGULF ANY EXCESS POWDER..

THAT QUESTION CMES UP EVERY FEW YEARS. AND EVEN IF SOME HIGH ROLLER WROTE ABOUT IT A FEW GENERATIONS AGO DOESN'T NECCESSARILY MAKE IT TRUE. IN MY OPINION.

DUTCH SCHOULTZ

Greener, amongst others, tried cutting a barrel back until deflagration left unburned powder. He got to 2 inches beyond the charge IIRC before finding unburned powder. What he did find was that the velocity decreased. Despite the powder all burning early velocity does increase (up to a point) as barrel length increases nevertheless. We pay too little attention to the adiabatic expansion of the gases. A considerable part of the expansion comes not from the production of gases but from their expansion as it heats. This is one reason why Aubonne Swiss sporting powder uses slightly more saltpetre than is the normal optimum. Not to make more gas but to heat the gas further.

I see accuracy and barrel length has drifted into the thread. Leaving aside sight radius. For which older eyes need less as they work better with the rear sight further away from the eyes even if it shortens the sight radius. Your barrel bends like a spring when you fire. How much varies with the type but changing the charge produces a different harmony to the spring so the barrel points slightly differently as the bullet/ball leaves the muzzle. Doubters need only look up slow motion shots of an unmentionable AK on youtube to see the barrel visibly flex wildly. Thus different loads have different points of impact from this cause as well as from the change in velocity. They can work such that a greater charge with a higher velocity will result in a lower POI instead of a higher one as it catches the barrel flex at a different, lower point in the cycle. The muzzle of a thin modern unmentionable barrel can cycle through (exceptionally) a whole half inch of movement. A military musket probably moves least of all bar heavy target rifle barrels.

 

[Melnic]

Well, we know it can happen with smokeless :

This was posted on another forum. The fire ignites on the far left lane but if you notice, it spreads to powder on each of the other lanes as well. Unknown what they were shooting and if any defective shells were involved.

http://www.worldstarhiphop.com/videos/video.php?v=wshh8Rl4Tm75dOlsChIq

 

[Bad Karma]

Well, we know it can happen with smokeless :

This was posted on another forum. The fire ignites on the far left lane but if you notice, it spreads to powder on each of the other lanes as well. Unknown what they were shooting and if any defective shells were involved.

http://www.worldstarhiphop.com/videos/video.php?v=wshh8Rl4Tm75dOlsChIq

They were testing 12 ga incendiary rounds. That fire was not ignited nor sustained by smokeless powder ejecta.

Dutch, it appears that the old geezer, Greener, agreed with you. It’s a fairly well formed consensus.

 

[Greenjoytj]

There is a correlation to a point. There are velocity nodes where accuracy peaks. After optimal accuracy is reached, increased velocity will open the groups.

Until you find the next higher MV node point. Which may not be possible if you are already close or at the maximum powder charge recommend by the firearm manufacturer.

Do a ladder test at long range.

Compare all the shot targets.
Choose the load that prints in the center of other charge weights that were slightly lower and slightly higher. That’s the node point (barrel flex point) where the bullet exited a motionless muzzle.

What’s found on the snowy ground just in front of the muzzleloader after a shot is fired is not powder (any more) it’s ejecta, (clinkers and cinders). Powder goes down the bore. Ejecta comes out, fast and hot.

 

[robinghewitt]

But, ha ha, there is also the weight of the powder (both burning, unburnt and ash) that is moving along with the ball. I guarantee if you set the rifle on a smooth flat surface (ideally a frictionless one) and touch it off with a fuse it will move more than 0.2" in a direction opposite the ball's travel. ;-)

Nearly there, it moves 0.2" while the ball moves up the barrel then stops moving some time later when it hits me. The part I found most interesting was that it moves 0.2" regardless how fast the ball goes.