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9/19/2017 7:27:10 PM
Posted: 3/29/2006 3:47:20 PM EDT
[Last Edit: 3/30/2006 8:03:19 AM EDT by Christian_Gun_Nut]
I was testing out the new chrono and I put together the following data. The fragmentation velocities are from the previously posted fragmentation chart
www.ar15.com/forums/topic.html?b=3&f=16&t=189353
I have no way to verify them so if they are incorrect, let me know.
I used an online ballistics calculator to get the predicted fragmentation range from the measured velocity:
www.eskimo.com/~jbm/ballistics/traj_basic/traj_basic.html

The chrono was 15ft from the muzzle and the temp was around 70 degrees.

Hornady TAP, 75 gr, 16 inch barrel, 1 in 9 twist
2590.0
2552.0
2557.0
2520.0
2513.0
2519.0
2529.0

Overall Avg Velocity 2540.0
Overall Max Velocity 2590.0
Overall Min Velocity 2513.0
Overall Avg Variance 77.0

Fragmentation Velocity from 223 fragmentation chart: 2300 fps
Fragmentation distance of min velocity: 100 yds
Fragmentation distance of avg velocity: 110 yds
Fragmentation distance of max velocity: 135 yds


Black Hills New - Red Box,75 gr,16 inch barrel, 1 in 9 twist
2551.0
2599.0
2613.0
2603.0
2552.0
2606.0
2527.0
2608.0
2555.0
2611.0

Overall Avg Velocity 2582.5
Overall Max Velocity 2613.0
Overall Min Velocity 2527.0
Overall Avg Variance 86.0

Fragmentation Velocity from 223 fragmentation chart: 2300 fps
Fragmentation distance of min velocity: 100 yds
Fragmentation distance of avg velocity: 125 yds
Fragmentation distance of max velocity: 140 yds


Black Hills Reman., 75 gr, 16 inch barrel, 1 in 9 twist
2579.0
2521.0
2582.0
2464.0
2568.0
2530.0
2531.0
2561.0
2524.0
2547.0

Overall Avg Velocity 2540.7
Overall Max Velocity 2582.0
Overall Min Velocity 2464.0
Overall Avg Variance 118.0

Fragmentation Velocity from 223 fragmentation chart: 2300 fps
Fragmentation distance of min velocity: 75 yds
Fragmentation distance of avg velocity: 105 yds
Fragmentation distance of max velocity: 125 yds

I also tested some XM193 for reference:
Federal XM-193, 55 gr, 16 inches, 1 in 9 twist
3053.0
3054.0
2984.0
3028.0
3052.0
3070.0
3073.0
3037.0
3079.0
3016.0

Overall Avg Velocity 3044.6
Overall Max Velocity 3079.0
Overall Min Velocity 2984.0
Overall Avg Variance 95.0

Fragmentation Velocity from 223 fragmentation chart: 2700 fps
Fragmentation distance of min velocity: 75 yds
Fragmentation distance of avg velocity: 90 yds
Fragmentation distance of max velocity: 95 yds

BH RB 75gr(23.00 per 50, 46cents/rd)
Hornady 75gr TAP (15.00 per 20, 37.5 per 50, 75cents/rd)
BH BB 75gr(20.00 per 50, 40cents/rd)

Check out this thread as well:

www.jobrelatedstuff.com/forums/topic.html?b=1&f=9&t=444423

Based on the info above, I plan to start using more BH Red Box. It is only 6 cents more per round than the BH BB and had the best performance of the three 75gr rounds tested. I did an earlier test on the BH BB and it was much more variable. This time I removed the rounds with obvious case issues(dents, etc) and it did a bit better.
Link Posted: 3/29/2006 4:13:54 PM EDT
Good gravy,

That's some info.

Thank you very much,
Scott
Link Posted: 3/29/2006 5:06:52 PM EDT
[Last Edit: 3/30/2006 5:22:22 AM EDT by ChuckT]
Thanks for some good info!

ETA: Shouldn't the Blue Box and Red Box have the same velocity, give or take? What would account for the difference?
Link Posted: 3/30/2006 3:33:09 AM EDT
Very good job!


Blue Box Black Hills 75

FRAG Distance of min velocity 75 yards ( Not bad for a 223 spec round )

XM193

FRAG Distance of min. velocity 75 yards

BTW the 250 rds of Blue Box Black Hills 75gr. and the 500rds of 77gr. HAVE NO DENTS and look very Pretty
Link Posted: 3/30/2006 8:14:42 AM EDT
[Last Edit: 3/30/2006 10:38:53 AM EDT by Christian_Gun_Nut]
These are the results from the Black Hills Blue box when I didn't screen the rounds for dents. All the brass was nice and shiny and looked pretty but it didn't perform very well. By the way, these rounds are all from the same box as the rounds above. Conditions at the time of this test were essentially the same, 70 degrees, 15 ft from the muzzle.

Black Hills Reman., 75 gr, 16 inches, 1 in 9 twist
2549.0
2512.0
2445.0
2492.0
2478.0
2460.0
2492.0

Overall Avg Velocity 2489.7
Overall Max Velocity 2549.0
Overall Min Velocity 2445.0
Overall Avg Variance 104.0

Fragmentation Velocity from 223 fragmentation chart: 2300 fps
Fragmentation distance of min velocity: 65 yds
Fragmentation distance of avg velocity: 90 yds
Fragmentation distance of max velocity: 115 yds

I still think for an extra $3 a box I will stick with the Black Hills Red Box. It is possible I just got a lot number with a lot of marginal brass, because others seem to love the Blue Box. My experience so far has been mixed. Some good, some not so good. YMMV
Link Posted: 3/30/2006 8:18:30 AM EDT
Red box for shtf mode
3 bucks aint bad!
Link Posted: 3/30/2006 10:55:59 AM EDT

Originally Posted By ChuckT:
Thanks for some good info!

ETA: Shouldn't the Blue Box and Red Box have the same velocity, give or take? What would account for the difference?



I thought the same thing. However, my chrono results show something different. I am no expert, but if I were to guess, I would say that the difference is due to the recycled brass. Screening for dented cases raised the Blue Box performance considerably. Also, one of the links above talks about the recycled brass being slightly out of spec. This may cause more rounds to have low velocities. Most of the Blue Box rounds are right there with the Red Box. It is the higher number of outliers that draws down the average velocity. Just my best guess, nothing to prove or disprove the theory.
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