Home Forums Hunting & Shooting Muzzleloaders round balls BC, any idea ?

Hi guys, does someone have an idea of the BC of lead round balls ?

One, IIRC.

Not much Why need a BC they kill 125 yards

id say not very much of one. those Scorpion sabot 300 grainers or great plains 385 grainers with 120 grains or so would probably get you to 200 yards no prob.

check this out:
Ballistic Coefficient In order to calculate the trajectory of a bullet in flight, its ability to push aside the air and retain energy must be known. This property is known as the bullet's Ballistic Coefficient (BC). To calculate an accurate BC for any given bullet requires actually shooting it many times at various velocities, and measuring it's change in velocity over range. There is a simple way to approximate the BC for a round ball, though, so we can play around with theoretical trajectories.
For a round ball traveling more than 1300 fps:

B.C. = Ball Wt. in grains divided by (10640 x ball dia. x ball dia.)

Example: For a .535 ball weighing 230 grains, 230 divided by (10640 x .535 x .535) = a BC of .0755. Lyman's Black Powder Handbook gives a BC of .075 for a .535 in. ball, so the agreement is good. This formula courtesy of "Lee in Denver"

Thanks a lot.

Don't need it for practical reason but for legal reason: we have downrange energy requirement for rifle use in hunting purpose.

If I try to hunt with a ML I have to be able to convince game rangers I reach the required energy which is 970 j @ 100 m for roe deer and 2200 j for any other stalked game and driven hunts.

thats a new one Where do you live ?

sorry to say but your not going to get the 970 ftlb @ 100 with a RB even with heavy loads , tell you get up around a 1 bore maybe even a 2 bore .
if you go to a conical , you will .

As to the ballistics coefficient concerning RB . Myself , I long ago drop any idea of relating how it relates to RB�s in practical use .
I know some folks are really into the coefficients , but I have very seldom found the numbers to actually be close to factual when it came to RB

no, it's not new, I always knew that rule here in South Belgium. And if in my particular area we use to burn tons of BP a year in muskets for folkloric & reenactment purpose, I know nobody huting with BP.

I have one option: at the moment, some games can get killed with smoothbore long guns (meaning shotguns) and as long as the caliber is 20, 16 or 12 gauge and the ball deforms itself on impact there is no energy requirement. So a 20 gauge fowler could be used but the accuracy and practical range will be reduced. That rule is a recent one but could be discontinued as easily as it was introduced.

to meet downrange energy requirements youll need conicals or sabots or a lot of powder and heavy ball.i think .54 retains more downrange energy than .58 but in all reality I know the law but its not foot lbs that kills things. Pedersoli makes a .72 rifle with a heavy ball but its not rated for high charges. If you want to meet downrange energy requirements with round bsalls you need a custom muzzleloader like a .69 from October Country custom muzzleloaders that is rated for 250 or so grains of powder and all the way up to 8 bore. Or if you really have money, get an 8 bore double rifle from Stolzer and Sons, 12-1500 grain conicals and 400 grain powder max.

I have dropped a whitetail buck at 115 yards roughly in its tracks with a .530 patched roundball. 90 grain fff goex. Ball was just under hide in opposite shoulder, quartering away. Put it where it counts it will take game no problem.

Sure it works but it's a matter of legal requirement, not a lethality question.

i didnt realize you were in Belgium. i thought it was here in the states and i didnt know of any such requirements here .
A 12 gage ball wont make it unless your using a real heavy charge as even with 100 gr of 2F your just squeaking over 800ft lbs at 100 yards .
I would also agree that the ftlbs are much more then is actually needed IMO . However the law is the law .

Also with a smooth bore , if you take the time and practice , you wont be reducing your range all that much . Yes your group will be wider , but with the correct load and practice , you should be able to get a 4 to 6 inch group or tighter at 75 yards easy enough

970 Joules @ 100M, or 970 ft. lbs. @ 100M?

970 joules is about 715ftlbs

"I know some folks are really into the coefficients , but I have very seldom found the numbers to actually be close to factual when it came to RB."

I'm curious what it is about the information the BC gives that you find isn't necessarily accurate.

I like to figure the BC and approximate muzzle velocity to see what the trajectory and wind drift looks like. I've been schooled enough on how the small amount of energy and light sectional density doesn't mean squat as all too often that RB goes clean through if it's not found on the off side.

sorry guys , i didnt catch the J and just assumed we were talking ftlbs .
at 100 a 12 cage ball would do it if loaded with 90+ grains of 2F.
depending on the power of course

According to information I have seen, the ballistic coefficient of a .490" (.50 caliber) Round Ball is .068... not exactly a high figure.


Strength & Honor...

Ron T.

Now im talking RB backed with BP here not conical or modern smokless

well Trajectory for one and wind drift for another .
do you find your trajectories match the numbers , i dont .

i shoot allot of off hand long distance . we are talking 250-400 yards . a couple of the folks i sometimes shoot with , have to set back , work the numbers up and then go ; OK 3ft of drop , ....... then go , did anyone see where that went ?
sometimes they hit and then its suddenly proof how the numbers are right .
same with wind drift .
now maybe its all well and good if you have a steady wind and constant air density all the way to target .
But the fact is unless your shooting in a vacuum , you wont .

Ever seen a barrel that throws a ball in a spiral like a pitcher throwing a hook ball or a sinker . I have .
My main rifle also shoots a trajectory that low for the first few yards then begins to climb before dropping again . I know it does because I have checked it on a trajectory range .
The numbers wont show you any of that .
All to often I just find the charts and math when applied to the RB to be very much nothing more then proving a bumble bee cant fly . When in fact we all know that it does

I'm still breaking in my Deerstalker and shooting it at 50 yds.

Due to what I saw in the ballistics chart I'd keep my shots to 100 yds or so since it was the wind drift that was quite extreme (too much for me to try to figure out). This rifle was meant for stalking where the shots likely wouldn't get beyond 75 yds. On a very still day it might not be a stretch to shoot 125 yds (according to the figures).

I'm wanting a drop-in barrel or rifle with a faster twist that I can attach a Malcolm scope to for hunting beyond 100 yds, in which I'd use conicals or saboted bullets.

I find it interesting and unsettling that you see evidence that the figures are completely off. I like to know what's going on, or have a good idea.

This is the formula for figuring RB's BC's that I've seen:

B.C. = Ball Wt. in grains divided by (10640 x ball dia. x ball dia.)

Example: For a .535 ball weighing 230 grains, 230 divided by (10640 x .535 x .535) = a BC of .0755. Lyman's Black Powder Handbook gives a BC of .075 for a .535 in. ball, so the agreement is good. This formula courtesy of "Lee in Denver"

A .490" RB weighs 177 grns, which, according to the formula, has a BC of 0.069285.

Is this different than the formula you are using? Maybe this could account for some of the differing trajectories.