243 Winchester Rifle 55 grain Nosler B.T. Cartridge  | SD .133 | BC .276 | MV 3,900-fps Ballistics, Trajectory,
Windage in inches, Lead in Feet; Red Fox & Prairie Dogs

Range/Yds
0-yds
50
100
150
200
250
300
350
400
450
500
Vel/fps
3900
3694
3498
3304
3114
2933
2753
2589
2425
2270
2123
Energy/ft/lbs
1858
1668
1493
1332
1185
1051
927
818
719
629
550
Bullet-flight
of/sec
.04
.081
.125
.172
.222
.276
.331
.39
.454
.523
7½mph/11fps lead/lungs ½'
1'
1.4'
1.9'
2.4'
3'
3.6'
4.3'
5'
5.8'
10mph/14.66fps
lead/lungs
.6'
1.2'
1.8'
2.5'
3.25'
4'
4.9'
5.7'
6.7'
X
15mph/22fps
Lead-from
1'
2'
2.6'
3.8'
4.75'
5.8'
7'
8.4'
10.5'
12'
25mph/36.6fps
hrt/lungs
1.5'
3'
4.5'
6.2'
8'
9.75'
12'
14.3'
X
X
30mph/44fps
hrt/lungs
1.7'
3.6'
5.5'
7.6'
9.8'
12'
14.5'
X
X
X
35mph/51.3fps
hrt/lungs
2'
4.2'
6.5'
8.8'
11.4'
14.2'
17'
X
X
X
Drift@5mph
90º
.1"
.4"
.9"
1.6"
2.6"
3.9"
5.4"
7.3"
9.5"
12.2"
Drift@7.5mph
90º
.15"
.6"
1"
2.4"
3.9"
5.8"
8.1"
10.9"
14.3"
18.3"
Drift@10mph
90º
.2"
 0.8"
1.2"
3.2"
5.2"
7.8"
10.8"
14.6"
19.7"
24.5"
Drift@15mph
90º
.3"
1.1"
2.6"
4.8"
7.8"
11.6"
16.2"
21.9"
28.6"
36.3"
Zero Windage
Zero L/R
L/Rclks
4
7
10
12
15
18
22
25
29
250yd/zero
-1.6"
+.2"
+1.3"
+1.7"
+1.3"
zero
-2.4"
-5.7"
-10.5"
-16.8"
-24.8"
Traj. POI
clks up zero>
      clks up>
 zero
3
7
11
15
20
Drop" / fractions
divide" by Frac. =clicks
.125"
(.25")
.375"
.5"
.625"
.75"
.875"
1.0"
1.125"
1.25"
Range/yds
0-yds
50
100
150
200
250
300
350
400
450
500

In all tables: Lead is always in feet, wind drift and trajectory are always in inches, lead and wind drift are both at 90° angles.

Wind drift: A  45-degree wind drift angle isn't half the wind drift of a 90º-angle, but is three-quarters the drift. It has a 75 percent effect, even though the angle is only halfway between no drift effect and full drift effect. The drift effect is not proportional, due to the aerodynamic ballistics of a bullet in flight. Just remember that halfway between full and zero effect is nearly three-quarters the drift of 90-degrees.  Multiply the 90º drift by .75 for 45º drift. Memorize these aerodynamic ballistic realities.

Most scopes are One Quarter of an inch 1/4"or .25") per click at 100--yds scope, or (1/2" or .5") @200-yds
Clicks Minutes of Angle (MOA) is 1/8" @  50-yds; 1/4"@100-yds; 1/2"@200-yds.
Print small cheat-sheets for each bullet weight, BC, & particular load, etc.

Figure leads from heart/lung area on fox & coyotes.
Coyotes and deer can run up to 40 mph. Use the length of the animal at longer ranges to determine the length of a foot and the lead.

The 55 grain bullet may be okay on red and gray fox however, with a mere .133 sectional density it's a bit light for coyotes. Rick Jamison says an SD of .140 is the minimum for coyotes, an a lower limit of .210-SD for deer! A 150-gr .308-Cal, SD is .225; 165-gr has a .248-SD.

When it isn't too windy I'm going to use this 55 grain bullet in my .243 Winchester with a 4 by 12X scope for fox and coyote hunting and anything smaller.  I need to get and try a 70-gr bullet on coyotes, with 40.8-grs of RL-15, which is supposed to be a very accurate load.  I tried the 55-gr nosler BT at 50-yds on two in-line milk jugs filled with water. It blew the first one and the other one tight against it cracked open and lot all the water from the shock of the first one.

"Sectional Density" is always the same irrespective of bullet shape, here is a list of 6mm SD's: 55-gr .133; 70-gr .169; 75-gr .181; 80-gr .194;  87-gr .210; 90-gr .218; 95-gr .230; 100-gr .242. Here's the SD equation: SD is the ratio of bullet weight to the square if the bullets diameter.
Example: | .243 X's .243= .059049 (65-gr  / 7000 grs per pound= .0092857 / .059049= .157-SD) Figure your own caliber/bullet SD.

The 6mm 55 grain Nosler bullet ( .133-SD) has a higher BC than the 55 grain bullet .224 bullet which has a higher .157-SD; 60-gr  is .171-SD. Otherwise, it's my 243/06 wildcat on coyotes, with the 87 grain V-Max bullet, SD .210, BC .400. 

This is still a better performing cartridge/bullet combination than the 220 Swift or 22-250 combos. In my 243/06 Wildcat I tend to prefer the 87 grain Hornady V-Max varmint bullets as they are better in the wind and hold their velocity and energy better than the lighter 55 grain bullets. The 55 grain Nosler bullets, in the past, have been accurate in my old 722 Remington bolt action rifle. The recoil calculator says: recoil velocity is 8.61 fps | recoil energy, 8.63 ft/lbs | using 50.5 grs. H-414 powder, MV 3900 fps. That is mighty low recoil!

With the 55 gr. bullet, and 44 grs. of H-414 powder, the 220 Swift comes the closest in velocity at 3,833 fps | Recoil energy is 7.37 ft/lbs, recoil vel. is 7.95 fps, which is close to the 243 recoil figures. The range of bullet weights and total versatility allows the 243 Winchester to effectively cover the .224 or 22 centerfire cartridges! My late Uncle Viv Duncan loved the 220 Swift for shooting red fox, and could nail them on the run with regularity. Back in the 1960's he shot well over 100 red fox during some of those winters with it using a 40 grain bullet.

 I'm going to use the 250 yd zero for everything, it's too easy for me to misjudge the range and shoot over fox and coyotes with a 300 yard zero. judging range on coyotes in varied terrain can be tricky stuff.

These charts will give you a general idea of what it takes to gauge the speed, angle, and approximate lead required to make a killing shot on a coyote or on that once in a lifetime trophy buck that is headed for thick cover, and that will get away if you don't drop him in his tracks.

There ought to be variable speed moving targets on every rifle and handgun shooting range. The target system should be movable to various ranges and run at various angles. Practice is essential to improve those shooting skills and to further determine each individuals range limits on running game. Remember that nearly everything that is shot, with a shotgun's shot pattern, is running or flying and those shooting skills vary a great deal between individuals due to numerous factors, with practice being a major one.

Start at the shorter ranges until you become proficient and move up, limiting yourself to reasonable shooting ranges.
Wisconsin Red Fox 1960 era

Red foxes were running targets par excel lance in the 1960's

Darrell     udarrell   

HUNTING - SHOOTING - BALLISTICS - LEADING RUNNING GAME CHARTS 
Bullet flight time, wind drift, trajectory, etc.
Use Link above, Only --in case a search engine picked up this 243 page

 http://www.udarrell.com/leadingrunninggamerifle.html
 http://www.udarrell.com/ultimate_deer_cartridge.htm
 http://www.udarrell.com/wisconsin_coyote_hunting.html

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          Darrell Udelhoven - udarrell
          Posted: 08/04/01; Updated: 03/12/07
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