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50 and 54 caliber ballistics

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nebhunt

32 Cal
Joined
Dec 11, 2020
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Has anyone shot there rifles over a chronograph? I was trying to find out what down range energy and fps are for different loads at 100yds. I have a chronograph but just never shot my Hawken over it. Too cold to mess around with it right now.
 
I know many have used their chrono to clock fps with their muzzleloaders, but i always get false readings due to smoke, I think.

My Lyman black powder handbook has ballistic tables for the 50 and 54, from the muzzle to 300 yards, iirc. It also has velocities from barrels from 24" to 44" for most calibers, using goex and c&h powder, what was available at the time of testing.

What is the length of your barrel, what charge of powder? Prb's or conicals?

I can post some info if you wish.
 
I shoot a Hawken with a 28" barrel. The round ball I use 70 gr. of powder and the 350gr maxi hunter I use 90gr.
 
I bought a chronograph long ago specifically for centerfire reloading. But it has done great service with the muzzleloaders as well. When I started using it there was no doubt that velocity tables couldn't be trusted. Rather than a linear progression velocities increased (and astonishingly sometimes decreased) in jumps and starts with powder charge increases. In one case a 5 grain increase gave, say, 70 fps. But with the next 5 grain increase velocity increased by 250 fps! So one does need to know their rifles specific velocity in order to get correct ballistic numbers from the tables.
 
Since EVERYTHING can affect the velocity, the only way to KNOW is to measure it.
Lube, Ball size, patch thickness, brand of powder, length of barrel and a bunch more.
If you want exact - then measure YOUR GUN....
I use a magnetospeed strapped to the barrel. Works great.
 
I will probably just have to use an educated guess for now and when it warms a little I will drag out my chrono and see what actual numbers are. I too have used a chrono for over 25 years developing loads for rifles but never shot the Hawken over it.
 
If you are looking at longer range data - AFTER getting measured speed - shoot a target at 25 yards, then set the target at 100 yards and aim at the EXACT same place on the target - measure the true drop and feed that data into your Balistic Arc app. It will calculate all required energy data you are seeking.
See attached data for one of mine.
Sight is calibrated at 50 yards.
At 100 yards the drop drop ZERO at 50 to 1.4 mils at 100 - 1.4(mils) X 3.3 = 6.42" and delivered energy is 540 foot pounds.
This is my target load - when hunting is use a much stiffer load that keeps the energy up above 750.
FRONTIER.png
 
I have some muzzle velocities from the old George Nonte Black Powder Guide of 1969. It is not your exact load but it is a starting place.

370 grain Lyman/ 90 grains 3F
28 inch muzzle velocity = 1480fps.

Round ball 180 grains with .015 patch/ 70 3F
28 inch muzzle velocity = 1590fps

I hope this helps.
 
Ballistic tables are like any chart...just a guide and not prefect. My doctor friend says there's NO absolutes in biology, I think the same can apply here.

BUT.......centerfire reloaders and shooters have for decades relied on ballistic tables in the back of reloading maunals...and while its not PERFECT, it does give you a place to start and something better than a SWAG. In my own use of them with a 30-06 the drop was almost spot on, allowing me to make some pretty long range shots.

Using the Lyman ballistic tables for the 58 cal 500 gr minie is also about spot on, for me, up to 200 yards. I regret I haven't shot further. This was at targets, not game.

Here's what Lyman published regarding 50 cal prb loads, 28" barrel and FFFg powder.
70grs, 1587fps & 1005 ft/lbs. at muzzle, 956fps and 365 ft/lbs @100yds
Sighted in at 50yds, drops 1.68" @75yds, -5.31" @100yds., -11.30" @125yds.
Energy; 1005 ft/lbs @muzzle, 575 ft/lbs @50yds, 312 ft/lbs @125yds

With a 370gr conical 90gr FFFg gave 1480 fps and 1797 ft/lbs @muzzle, 1038fps & 860ft/lbs @100yds.
sighted in at 50yds, drops 1.4" @75yds, -4.3" @100 yds, -9.2" @125yds.

So the trajectory of the 2 bullets are close, but the conical has lots more retained velocity and energy at the same ranges for a 20 grain increase in powder.
Btw, a 90 gr load of FFFG w/ a prb gives 431 ft/lbs @100 yards...I figured I'd be crucified if I didn't include that piece of info.

Remember their data used FFFg for the 50 cal, and you are using FFg, this WILL make a difference.

I'm gonna kick the hornets nest...their data, while dated, is still relevant imho. And they did lots of testing using FFg vs FFFg and their test showed you could use 40% less FFFg and get the same velocity as 40% more charge of FFg. At least in the 54 caliber you could. Here's some of their findings.

Example
54 cal prb
100 grs FFFg =1740fps
100grs FFg= 1538fps
140grs FFg= 1779fps.

You can find the book used for cheap, try abebooks, they seem to have it most times I've looked.
 
Sounds like I have a fun project for this spring. I will set up the chrono and shoot the Hawken with prb and maxi. I will also use fog and fffg to see what happens. Of course I will record group size with each load. When I get it all put together I will post my findings
 
I chrono'd my .54 PRB (Hornady swaged) out of my 36" barrel with 120 gr. of loose Triple 7 at 1916 ps.
 
Has anyone shot there rifles over a chronograph? I was trying to find out what down range energy and fps are for different loads at 100yds. I have a chronograph but just never shot my Hawken over it. Too cold to mess around with it right now.
At a hundred yards the velocities get a lot close together. A round ball in a .50 can be gotten to 2200 fps. But slows to about 1100 fps at a hundred yards. One fired at 1100 fps slows to about 800 fps at a hundred.
A .54 will keeps its velocity a little better then a .50
A.50 can get higher energy at range. But on most shooters feel a .54 is more a better killer.
Conical hold velocity much better then ball.
Of course if you shoot conical your mama wears army boots and your dogs ugly and your home brew is flat and your straight up eggs have busted yokes and all that.
 
once you establish FPS from chronograph the math is simeple
square the velocity which is multiplyinging it by itself
Divide by 450250
multiply that number by weight in grains that will give you Kinetic energy
for example 1600x1600= 2,560,000 divide by 450250=5.685730149916 x 177 grain .490 roundball =1006.37 lbs kinetic energy.
knowing that if you know the range the sectional density and ballistic co-efficient you can look at a chart and get a reasonable estimate
so you substitute the weight i listed for a roundball for what weight your ball or bullet weighs
 
Silly question, perhaps: why do you want to know this? Trajectory estimation or trying to figure out how it will perform on game?
 
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