Update 5/26/17: Added data for 223 Speer GD 64 grain.
- 10.5" barrel: Green Mountain 1:7, chrome lined.
- 16" barrel: BCM 1:7 CHF, chrome lined.
- Chronograph: CED M2 with start sensor 10' from the muzzle. No problems with muzzle blast.
- Weather/location: 70 - 78 degrees temperature, clear, sunny day with a slight breeze, elevation of 457' ASL.
- Etc: All equipment and shooter under canopy with no direct sunshine on them. Each ammunition string supplied by a 20 round magazine with seven shots per string to minimize barrel heating and ~ five seconds per shot per string. All numbers provided by the chrono except energy, which was computed by an Excel tabulated data column referencing the chrono supplied data.
-------- 10.5" --------- | --------- 16" ----------
Kinetic| Kinetic
Avg Vel SD Energy | Avg Vel SD Energy
- Black Hills(new) 223 68 gr. hvy match HP---- 2253.1 25.2 766.4 | 2569 16.4 996.3
- Black Hills(reman) 223 75 gr. match HP------ 2250.3 16.8 843.2 | 2534 11.2 1069.2
- Speer 223 Gold Dot HP 55 grain--------------- 2612.7 14.9 833.5 | 2953.1 13.8 1064.8
- Speer 223 Gold Dot HP 64 grain--------------- 2297.3 23.6 747.5 | 2623.6 23.1 978.0
- Speer 223 Gold Dot HP 75 grain--------------- 2213.7 12.2 816.0 | 2504.7 10.7 1044.6
- GECO 556 55 gr. FMJ---------------------------- 2702.2 29 891.6 | 3053.6 20.9 1138.6
- Fed AE 556 XM 855 62 gr. penetrator-------- 2657.7 16.5 972.2 | 3021.4 15.8 1256.5
- IMI 556 55 gr.M193FMJ------------------------- 2672.7 25.3 872.2 | 3049.4 28.9 1135.4
- IMI 556 62 gr. M855 62 gr. penetrator------- 2637.3 18.5 957.4 | 2980.9 27.8 1223.1
- IMI 556 77 gr, OTM LR Mod 1------------------2448.9 18 1025.2 | 2729.4 10.7 1273.5