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nekshot
07-10-2017, 08:07 AM
I am sure this is a stupid question but it recently has bothered me. In a cross wind does a 50-54 cal round barrel compare to a factory 223 or factory 30-30. Where I shoot wind is not a issue so I cannot conduct a test with out a lot of effort and in this hot humid weather it aint gonna happen. Asking is easier and some folk just love dipping into this type of reality so they can help fellas like me! Assuming normal loads no jacked up performance.

GhostHawk
07-10-2017, 08:23 AM
Apples and oranges. Neither actually.

First off the bigger the ball/bullet the less wind effects it. Speed has an effect also.

So that small fast .223 is going to drift at a totally different rate than your dirty 30.


Like asking about drafting only your asking a F1 racer and an 18 wheeler driver. Different animal entirely. Same theory but the one example has almost nothing in common with the other.

The only real answer is to go out with a measured wind and shoot a few. Make notes and observations.

Steady is easier, better than gusty.

Crosswind drifts you more than with you/against you.

rosewood
07-10-2017, 08:24 AM
I would input into one of the ballistic calculators. You will need the BC for each projectile then input the velocity and cross wind. You can use the default pressure, temp etc or can input your local conditions. Should give you how much windage is needed to stay on target at a given range. Then compare the 3.

Rosewood

mooman76
07-10-2017, 09:47 AM
Not a stupid question at all. I agree with GhostHawk on this. MLs with RBs usually aren't shot long distances where wind would effect it more and of coarse comparing a big RB like the 54 will certainly be effected less. Now the smaller RB like the 32 can have allot of wind drift especially when it approaches 100y and beyond where it looses power quickly and of coarse being lighter will drift considerably. Even with the 32 being effected by wind drift, I don't believe it is comparable to center fire rifles. With the shape of the RB drift would be more uneven than it would be with a bullet. In other words it would probably drift up or down more, not just to the side.

rodwha
07-10-2017, 01:28 PM
A .50 cal loaded with 70 grns of Olde E will give about 1825 fps. A .490" lead ball has a BC of 0.069. At 100 yds with a 10 mph 90* crosswind it shows to move 10.2".

Hornady shows their 150 grn RN fired at 2100 fps. That bullet has a BC of 0.186. At 100 yds it has moved just 2.9" in the same wind at the same distance.

Hornady's 55 grn SP has a BC of .235 and is traveling at 3240 fps. It has moved just 1.2" at 100 yds.

These figures are at 900' elevation where I am.

KCSO
07-10-2017, 01:58 PM
In a 40 mph wind at 100 yards you need to hold 4inches ahead of the paper on a Buffalo target with a 440 round ball and ahead of the buff's nose with a 50. Round balls work different in the wind than a bullet and no wind is the same direction speed shifts all have to be estimated on the range and a few practice shots down range then when the flags are the same as the practice you may know where to hold.

nekshot
07-11-2017, 08:34 AM
thanks for the input, and I will settle the issue when hay season is past.

indian joe
07-11-2017, 08:36 AM
In a 40 mph wind at 100 yards you need to hold 4inches ahead of the paper on a Buffalo target with a 440 round ball and ahead of the buff's nose with a 50. Round balls work different in the wind than a bullet and no wind is the same direction speed shifts all have to be estimated on the range and a few practice shots down range then when the flags are the same as the practice you may know where to hold.

The ballistics calculators tell us that the harder you push a round ball the more it is deflected by the same wind over a given distance - that made no sense to me but every time I look it up I get the same answer ! - What I do know is it dont take much breeze to shift a 50 or 54 roundball 4 to 6 inches at 100 yards

bedbugbilly
07-11-2017, 09:39 AM
A good question!

I can remember shooting in the "gunmakers match" down at Friendship at the Nationals one year. You get one shot at a the same target at an unspecified distance. There was a gentle cross breeze - have no idea how much. Different shooters with different guns and a wide variety of calibers.

I was shooting a 36 caliber Virginia style flintlock that I had just finished before leaving for the Nationals. It turns out that the target was at 130 yards. Breeze was blowing left to right and the target is a larger round wood plate. I tried to figure the "kentucky windage" - aimed at the eft edge and my ball was blown to the right enough that I never touched the plate. Everyone was having difficulty regardless of how big their bores were. It really made me aware of just how much a cross wind affects a round ball flight.

Can't compare it to the modern cartridges as I really haven't shot my 30-30 or 8mm at those distances.

Nobade
07-15-2017, 08:22 PM
Some years ago I was playing around at the range, trying to hit the 500M ram silhouettes with my 1863 musket loaded with balls. Crosswind was in the 20 mph range, really stout. Ended up having to hold something like 100 feet for windage to get anywhere near the one I wanted to hit. Can't remember if I ever hit it, but that sure was a lesson in round ball wind drift. In comparison I had to hold maybe a foot off the edge to hit it with my 260.

-Nobade