Muzzleloading Question

[Cannon]

Say you needed to find out muzzle energy and velocity for a black powder pistol but you didn't have a chrono. Is there a way to get an accurate figure using barrel length, bore diameter, projectile weight and powder grains? If so what would the figure be for this info-

 

Barrel Length - 19cm

Bore Diameter - .50"

Projectile Weight (Lead Ball) - 176 Grains

Powder Weight (FFG Black Powder) - 80 Grains

 

Any help appreciated

[Imperfection]

80 grains of BP??? What calibre is it??? Im guessing its a double barrel pistol in perhaps .54 or .75 calibre?

 

Edited to add:Just saw its a 1/2" barrel so 50cal. 80 grains of BP does sound a lot for a pistol-i know people who use 60 in a rifle of same calibre and get respectable grouping.I bet it kicks like a mule! Someone i know had a single barrel .50 pistol and even when hiked right up with Pyrodex (he refused to turn to the dark side) it was doing something like 750fps.

Edited May 2, 2013 by Imperfection

[Underdog]

Too many variables.

Put whatever you want in but I bets some of that 80grn is wasted.

If thats what it takes to shoot then.....make a good hunting load.

 

U.

[Vince Green]

80 grains is far too much powder for a .50 cal pistol. 40 grains is about max and should give around 950-1000 fps but its very unlikely that will produce best accuracy.

More accuracy probably with 30 grains at around 800 fps

Edited May 3, 2013 by Vince Green

[Cannon]

80 grains was maybe a tad enthusiastic, but I was trying to establish what the maximum fps and ft/lbs would be using an 80 grain load. These replies have been very helpful lads. Much appreciated

[JonathanL]

As others have said, 80 grains is way, way too much. The noise and recoil will be horrendous. The Walker Colt was designed for a max charge of 60 grains, all be it with a slightly smaller bullet, and that had a reputation as a fearsome pistol.

 

The problem is that with a round ball you reach a point of rapidly diminising returns the faster you push it because the more rapidly air resistance slows it down. I forget the precise figures but you reach a point beyond which it isn't worth making it go any faster. You might get it to 3,000 fps but within about 50 feet it's slowed to about half that at which point it's rate of deceleration continues much more slowly. Hence, it was a pointless exercise getting it to 3,000 fps in the first place. Not sure if that makes sense?

 

J.

[Vince Green]

Actually, with blackpowder once you exceed the amount of powder that can be burned in the barrel the velocity doesn't increase any more and may actually start to go down again. The rest just goes unburnt out of the end of the barrel.

 

Its fairly forgiving from that point of view but its wasteful.

[Underdog]

Yes.

 

Black powder guns make heir strength from throwing heavy bullets. Thats why the big game guns that used ball where huge.

Then long heavy bullets came on the scene.

 

Black powder is a low pressure fuel and like a PCP air gun needs some barrel to be efficient and have some time to accelelrate the pellet so does bp.

 

Hope this helps and I am not trying to be a bighead!

 

U.

[Cannon]

Sound information lads cheers. Just found out the recommended maximum black powder load is 20 grains. A quarter of what I had originally thought was needed. So what would the fps and ft/lbs be from a 19cm barrel firing a .50 176 grain round projectle with 20 grains of FFG black powder be? I have hunted the net trying to find the answer to no avail. Can it even be worked out?

[Vince Green]

20 grains wouldn't be maximum, 20 grains is a pretty typical target load. Why are you so concerned about velocity and energy? if it is about complying with range limitations you should be more concerned that most ranges are limited to .455 calibre

Edited May 8, 2013 by Vince Green

[Cannon]

It is to comply with range limitations. This information has been requested by the police. They want to know muzzle velocity and energy so that they can check it against the range. The firearm manufacturer has yet to get back to me from over a week ago, so not holding out much hope of getting weapon specific ballistic stats from them. However, they do recommend a maximum of 20 grains of ffg for use in this firearm.

[JonathanL]

What type of range are you shooting it on? There is no such thing as a MoD safety certificate issued to non military ranges any more, and hasn't been for years, so how do the police assess whether the range is suitable? What qualifications do they have to make this judgement? Probably none, I would guess.

 

J.

Edited May 9, 2013 by JonathanL

[Livefast123]

Does this help at all, at the bottom is data for pistols and revolvers.

 

http://hodgdon.com/PDF/muzzleloading_manual_2008.pdf?CHECKBOX_1=on

 

20gr seems extremely low for a .50, thats a target load on my .44 Remington 1858!

[Cannon]

I am not sure what qualifications the police hold to make judgements on range limits, but the way things are going with firearms over here at the minute it's in my best interests to accommodate their requests. I believe diplomacy is the name of the game here. We shall see what the outcome is based on the evidence I provide. Many thanks for the help lads

 

P.S- Livefast that data sheet was a good find!

[Livefast123]

I use it for my muzzleloading velocities etc, tried a 30gr load of 777 in the 1858, now that sings!

[Underdog]

Why don't we accomodate their request in full and surrender our licences then?

 

Give them hell! I do!

 

U.