Here's some comparative calculations. I used Barnes XLC, 24" barrels, and kept pressures under 65k for all three.
Trajectory and energy are not significantly different.
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Gun / Ammunition : .30-06 Spring.
Bullet : .308, 165, BAR 'XLC' BT 30857
Powder: 58.5 gr W760
Pressure: 63,795 lbs-psi
Bullet weight : 165 grains or 10.69 grams
Muzzle velocity : 2973 fps
Crosswind speed : 10 Mph
Ballistic Coefficient(s) (G1):
C1=0.496>0 fps;
Optimum trajectory information : Max. point blank range (P)=305 Yds. with a
zero range set to (X)=261 Yds. and max. ordinate above LOS at range (M)=150 Yds.
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Sight-in clicks, 1 click = 2.66 cm/100 yd. or 1.047 in/100 yd.
Height of sight above bore axis = 5.08 cm or 2.00 inch
Gun is zeroed-in at 200 yards, by
sighting-in at level firing
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Range Velo Time of Energy Path Deflection Total Sight correction Target
city flight to at crosswind drop for setting new lead
LOS of 10.0 Mph zero range 33 fps
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�Yards fps s ft.lbs. in. in. MOA in. Clicks MOA yds �
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| 0 2973 0.0000 3238 -2.0 0.0 ----- 0.0 ------ ----- 0.00
| 50 2888 0.0510 3055 +0.1 0.1 0.19 0.5 -0.3 -0.27 0.56
| 100 2804 0.1038 2880 +1.2 0.5 0.48 2.0 -1.2 -1.18 1.14
M 124 2765 0.1298 2800 +1.4 0.8 0.63 3.2 -1.1 -1.05 1.42
| 150 2722 0.1583 2715 +1.2 1.2 0.78 4.7 -0.8 -0.77 1.73
X 200 2642 0.2145 2557 0.0 2.2 1.07 8.5 0.0 0.00 2.35
| 250 2563 0.2723 2406 -2.5 3.5 1.35 13.6 +0.9 +0.94 2.98
P 258 2550 0.2817 2383 -3.0 3.8 1.39 14.6 +1.1 +1.10 3.08
| 300 2485 0.3316 2263 -6.2 5.1 1.62 20.0 +2.0 +1.97 3.63
| 350 2409 0.3923 2126 -11.3 6.9 1.88 27.7 +3.1 +3.08 4.29
| 400 2334 0.4554 1996 -17.9 9.1 2.17 37.0 +4.3 +4.27 4.98
| 450 2261 0.5208 1872 -26.2 11.8 2.49 47.9 +5.6 +5.55 5.70
| 500 2188 0.5886 1754 -36.2 14.8 2.83 60.5 +6.9 +6.91 6.44
| 550 2117 0.6586 1642 -48.0 18.2 3.17 75.0 +8.3 +8.33 7.20
| 600 2048 0.7306 1536 -61.7 22.0 3.51 91.3 +9.8 +9.82 7.99
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[code]
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Gun / Ammunition : 7 mm Rem. Mag.
Bullet : .284, 140, BAR 'XLC' BT 28455
Bullet weight : 140 grains or 9.07 grams
Powder: 70gr RL22
Pressure: 64,734 lbs psi
Muzzle velocity : 3240 fps
Crosswind speed : 10 Mph
Ballistic Coefficient(s) (G1):
C1=0.469>0 fps;
Optimum trajectory information : Max. point blank range (P)=329 Yds. with a
zero range set to (X)=282 Yds. and max. ordinate above LOS at range (M)=164 Yds.
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Sight-in clicks, 1 click = 2.66 cm/100 yd. or 1.047 in/100 yd.
Height of sight above bore axis = 5.08 cm or 2.00 inch
Gun is zeroed-in at 200 yards, by
sighting-in at level firing
-------------------------------------------------------------------------------------
Range Velo Time of Energy Path Deflection Total Sight correction Target
city flight to at crosswind drop for setting new lead
LOS of 10.0 Mph zero range 33 fps
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�Yards fps s ft.lbs. in. in. MOA in. Clicks MOA yds �
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| 0 3240 0.0000 3263 -2.0 0.0 ----- 0.0 ------ ----- 0.00
| 50 3144 0.0471 3072 -0.1 0.1 0.28 0.4 +0.2 +0.25 0.52
| 100 3050 0.0956 2891 +0.9 0.5 0.51 1.7 -0.8 -0.82 1.05
M 129 2997 0.1243 2791 +1.0 0.9 0.63 2.9 -0.7 -0.75 1.36
| 150 2958 0.1454 2720 +0.9 1.2 0.73 4.0 -0.6 -0.59 1.59
X 200 2869 0.1967 2557 0.0 2.0 0.97 7.2 0.0 0.00 2.15
| 250 2781 0.2500 2403 -2.0 3.3 1.24 11.5 +0.8 +0.76 2.73
P 268 2749 0.2696 2349 -3.0 3.8 1.34 13.3 +1.1 +1.07 2.95
| 300 2694 0.3050 2256 -5.1 4.8 1.53 16.9 +1.6 +1.64 3.34
| 350 2610 0.3619 2117 -9.5 6.7 1.82 23.5 +2.6 +2.59 3.96
| 400 2527 0.4203 1984 -15.1 8.8 2.10 31.4 +3.6 +3.60 4.60
| 450 2445 0.4802 1858 -22.0 11.2 2.37 40.6 +4.7 +4.66 5.25
| 500 2365 0.5422 1739 -30.3 13.9 2.66 51.2 +5.8 +5.78 5.93
| 550 2287 0.6067 1625 -40.2 17.2 2.98 63.5 +7.0 +6.99 6.64
| 600 2210 0.6738 1518 -51.9 20.8 3.31 77.4 +8.3 +8.26 7.37
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[/code]
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Gun / Ammunition : .270 Win.
Bullet : .277, 130, BAR 'XLC' BT 27754
Bullet weight : 130 grains or 8.42 grams
Powder: 55 gr IMR 4350
Pressure: 63,338 lbs psi
Muzzle velocity : 3141 fps
Crosswind speed : 10 Mph
Ballistic Coefficient(s) (G1):
C1=0.458>0 fps;
Optimum trajectory information : Max. point blank range (P)=318 Yds. with a
zero range set to (X)=273 Yds. and max. ordinate above LOS at range (M)=145 Yds.
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Sight-in clicks, 1 click = 2.66 cm/100 yd. or 1.047 in/100 yd.
Height of sight above bore axis = 5.08 cm or 2.00 inch
Gun is zeroed-in at 200 yards, by
sighting-in at level firing
-------------------------------------------------------------------------------------
Range Velo Time of Energy Path Deflection Total Sight correction Target
city flight to at crosswind drop for setting new lead
LOS of 10.0 Mph zero range 33 fps
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�Yards fps s ft.lbs. in. in. MOA in. Clicks MOA yds �
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| 0 3141 0.0000 2846 -2.0 0.0 ----- 0.0 ------ ----- 0.00
| 50 3045 0.0485 2675 0.0 0.1 0.26 0.4 +0.1 +0.07 0.53
| 100 2951 0.0984 2513 +1.0 0.5 0.49 1.8 -1.0 -0.95 1.08
M 127 2901 0.1260 2429 +1.1 0.8 0.62 3.0 -0.9 -0.86 1.38
| 150 2859 0.1499 2359 +1.0 1.2 0.74 4.2 -0.7 -0.66 1.64
X 200 2770 0.2034 2213 0.0 2.2 1.04 7.7 0.0 0.00 2.22
| 250 2682 0.2587 2074 -2.2 3.5 1.34 12.3 +0.8 +0.84 2.83
P 263 2659 0.2734 2040 -3.0 3.9 1.42 13.7 +1.1 +1.07 2.99
| 300 2595 0.3158 1943 -5.6 5.1 1.64 18.1 +1.8 +1.78 3.45
| 350 2511 0.3745 1818 -10.3 7.1 1.93 25.2 +2.8 +2.80 4.10
| 400 2428 0.4347 1700 -16.2 9.3 2.21 33.5 +3.9 +3.87 4.75
| 450 2346 0.4973 1588 -23.7 11.9 2.52 43.4 +5.0 +5.03 5.44
| 500 2266 0.5625 1481 -32.8 15.0 2.86 54.9 +6.3 +6.26 6.15
| 550 2188 0.6302 1381 -43.6 18.5 3.21 68.2 +7.6 +7.58 6.89
| 600 2111 0.7003 1286 -56.3 22.4 3.56 83.3 +9.0 +8.96 7.66
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