Went to the 600yd range to test some Heavy and Light
CCI 450 primers.
Now, before you say WOW, that was terrible, that was the intent. To find what the
extreme heavy and light primers from a brick of primers would do.
22N AR-15, Berger 85.5, 31.
7gr SB 6.5
Test 1, 10 shots
Grouped some 3.62/3.63 light ones, and some 3.73/3.75 heavy ones, 5 each, shot round robin light first.
The light/ heavy individual velocities, Garmin Xero:
Light 2989.3
*Heavy 3039.3*Light 2975.2
Heavy 3007.7Light 2996.5
Heavy 3018.5Light 2993.2
Heavy 3011.4Light 2997.4
Heavy 3015.7Test 2
Went back 2 weeks later and did a larger sample with individual primer weights recorded and post fired primer weight.
15 light, 15 heavy. Shot round robin heavy first. 22N AR-15, Berger 85.5, 31.
8gr SB 6.5
Shot order, Primer Weight, Fired Primer weight, Weight Loss, Garmin Xero muzzle velocity.
1 -- 3.765, 3.400, 0.365, 3036.830 - 3.625, 3.375, 0.250, 2989.2
2 -- 3.760, 3.390, 0.370, 3042.729 - 3.625, 3.360, 0.265, 2989.0
3 -- 3.765, 3.385, 0.380, 3054.428 - 3.620, 3.360, 0.260, 2987.4
4 -- 3.775, 3.405, 0.370, 3058.427 - 3.615, 3.370, 0.245, 2993.1
5 -- 3.755, 3.395, 0.360, 3050.226 - 3.610, 3.360, 0.250, 2977.4
6 -- 3.755, 3.395, 0.360, 3046.225 - 3.630, 3.380, 0.250, 2996.3
7 -- 3.750, 3.395, 0.355, 3037.824 - 3.630, 3.370, 0.260, 2982.8
8 -- 3.750, 3.385, 0.365, 3047.023 - 3.630, 3.370, 0.260, 2992.5
9 -- 3.750, 3.390, 0.360, 3055.422 - 3.635, 3.370, 0.265, 2987.9
10 -- 3.750, 3.390, 0.360, 3029.221 - 3.635, 3.365, 0.270, 3021.1
11 -- 3.740, 3.380, 0.360, 3055.120 - 3.635, 3.360, 0.275, 3010.1
12 -- 3.730, 3.385, 0.345, 3053.519 - 3.630, 3.360, 0.270, 3010.3
13 -- 3.730, 3.380, 0.350, 3063.018 - 3.635, 3.360, 0.275, 3013.2
14 -- 3.730, 3.380, 0.350, 3032.317 - 3.635, 3.370, 0.265, 3003.1
15 -- 3.730, 3.385, 0.345, 3044.616 - 3.640, 3.375, 0.265 2999.9
Range of primers: 0.165 grains
Range as fired: 0.045 grains
Range of weight loss: 0.135 grains
Extreme Spread of all 30 shots, Garmin Xero muzzle velocities 85.6 fps.
Extreme Spread of 15 HEAVY 33.8fps
Extreme Spread of 15 LIGHT 30.4fps
Picture of Shot Marker target of 10 shots 3/7/24 and first 10 shots on 3/21/24.
Shot marker was acting up (I think) on 3/24 ???
