Black Powder Ballestics

[VEARL]

Am inquiring about 50 Cal ballestics (velocity, a foot pounds & bullet drop at different yardage.
Found several showing the same weight of projectile and same powder charge.( 230 gr conical & a velocity of 1745 fps ) However the bullet drop was shown to be different on some charts.
According to the charts, if you are dead on at 25 yds, then you should be dead on at 100 yds
How many of you have found this to be accurate or misleading ?
Trying to use this in sighting in my rifles from a bench rest.
All replies are appreciated.

 

[zimmerstutzen]

Some charts do not take into account deceleration. Some do not factor the more rapid deceleration of balls/bullets fired at speeds above the speed of sound. Many calculators take neither factor into account. As an extremely rough minute of pie plate guestimate, the 25 yd - 100 yd thing is perhaps in the ball park, for moderate to average hunting charges. certainly for light charges it would not hold true.

I always sighted the gun for the 100 yd range and then adjusted for the short range as necessary.

 

[BrownBear]

The height of the sights (both front and rear) will affect that dramatically.

 

[mooman76]

Another thing that will effect it is barrel length and the fact that every gun is different. The figures are basically estimates.

 

[VEARL]

Since I do 90% of my shooting from the bench. I think that this would at least help in getting a shooter close to the 10 ring at 100 yds.
I agree with powder loads and sight heights playing a role in the final results.
If a person has access to a cornograph, I believe that this would save a lot of time spent in reaching the level of being sighted in.
I have two (2) rifles that are sighted dead center of a 1 inch bulls eye at 25 yds. Come warmer weather I will finish the sighting in process and will post my results then.

 

[Stumpkiller]

I have found there seems to be a lot of flexibility in what folks consider "dead on" at 25 yards to be.

At 100 yards all doubt is removed.

If you want to be sighted in at 100 yards that's where you should shoot. When "getting on the paper" with new sights 25 yards makes sense.

Where you sights meet on the rise and fall of the trajectory depends on the sight height over the bore as well as velocity and the projectile shape and density.

 

[coloradoclyde]

Trying to use this in sighting in my rifles from a bench rest.

One thing to consider is that sighting can change when shooting from a bench, compared to off-hand shooting.
Stock weld and eye alignment often change resulting in a different point of impact.

 

[Rifleman1776]

25 yards won't do much more than get you on paper. Charts can vary tremendously. Even the loading manuals for modern gun will tell you their results are only guides. The old Lyman black powder manual can help. But, since you have access to a range and bench rest, you can learn first hand for yourself. Work up your sweet spot load for accuracy at 50 yards then move out to 100 for the real test.

 

[VEARL]

True

 

[Elkeater]

110 yards is my max range. I sight in at 80 yards.

 

[Col. Batguano]

Where the gun is rested can have an effect on barrel harmonics, and point of impact and group size too, as do all the other things mentioned, including whether or not your ram rod is in or out.

In short, everything is connected one way or another to everything else.