Any chance I can get some load data from you for the 75gr? I am starting to collect data for using the 8208xbr so I can do some load development when I can get some components. Always like to know what other people see for comparison ONLY.
I have developed data for both the Hornady BTHP and the AMAX in my 5.56 chambered MVP (with 24" barrel). The BTHP load feeds and functions fine in either my MVP or AR, though I plan to re-tune it for my AR's 16" barrel.
During the load development process, I discovered that my MVP has a much longer chamber throat than my AR, though both are chambered for 5.56 NATO. I found that the AMAX, loaded to a COAL of 2.455" for my MVP would not chamber in my AR. After the fact, I realized the Hornady 9th Edition manual recommends a COAL of 2.390" in an AR. So, my AMAX data probably won't be of much use to you, but I will include it anyway.
All of the loads I have developed, so far, have been tuned for a specific velocity range from the 24" barrel of my MVP, so they may not perform as well from a different length barrel. If you have a chrono, knowing the velocity range you are after may be more useful to you than powder charge information. If you can tell me your barrel length and the brand of brass you plan to use, I might be able to help you with that.
I used LC brass and CCI 450 Small Rifle Magnum primers for all of my load development.
5.56 NATO
COAL 2.250"
Hornady 75 BTHP
CFE 223 @ 25.8
MIN 2901
MAX 2937
AVG 2919
SD 13
ES 36
5.56 NATO
COAL 2.455"
Hornady 75 AMAX
CFE 223 @ 26.3
MIN 2944
MAX 2962
AVG 2954
SD 9
ES 18
My loads developed with IMR 8208 XBR are about 1.5 grains above max in the Hornady 9th Edition manual. This data, especially, should ONLY be used for comparison purposes.
5.56 NATO
COAL 2.250"
Hornady BTHP
IMR 8208 XBR @ 24.2
MIN 2852
MAX 2875
AVG 2857
SD 9
ES 23
5.56 NATO
COAL 2.455"
Hornady 75 AMAX
IMR 8208 XBR @ 24.3
MIN 2826
MAX 2847
AVG 2836
SD 9
ES 21
