Gary L. Griffiths
New member
I have been reading conflicting information on using regular vs. MilSpec vs. Magnum primers in loading for .223 in the AR Platform. A couple of months ago, I bought a carton of CCI-41 primers, which seemed to be actually giving a slightly lower average velocity than regular CCI-400s. Finally, a week ago, I managed to find a box of CCI-450 primers, so I decided to test the three types of primer.
To test the primer variance, I loaded 30 rounds of .223, using new Lake City cases with 25.0 gr. AR-Comp under a Hornady 55-gr. V-Max bullet. Ten of the cases were primed with CCI-400s, ten with CCI-41s, and ten with CCI-450s. All charges were weighed on my new digital scale. I shot them this afternoon, recording the velocities with my new (to me) CED Millennium chronograph with the following results:
The CCI-400 standard primers gave an average velocity of 3054.40 fps, with a SD of 19.31.
The CCI-41 MilSpec primers gave an average velocity of 3068.90 fps, with a SD of 13.83.
The CCI-450 magnum primers gave an average velocity of 3054.60 fps, with a SD of 11.01.
In this test, the MilSpec primers proved slightly hotter (but only by 14 fps) than either the standard or magnum primers, and the magnum proved to be the most consistent.
As a check of my chronograph under the same weather conditions (mid-60s) I fired 10 rounds of Wolf Gold 55-gr. .223, which averaged 2982.80 fps, SD 28.09, and 10 rounds of Carl Gustav 62-gr LAP 5.56mm, which averaged 2980 fps, SD 12.82.
It would seem to me, that at least with AR-Comp powder, there is little difference between the three types of primer in terms of velocity, and virtually no difference between CCI standard and magnum primers.
FWIW
To test the primer variance, I loaded 30 rounds of .223, using new Lake City cases with 25.0 gr. AR-Comp under a Hornady 55-gr. V-Max bullet. Ten of the cases were primed with CCI-400s, ten with CCI-41s, and ten with CCI-450s. All charges were weighed on my new digital scale. I shot them this afternoon, recording the velocities with my new (to me) CED Millennium chronograph with the following results:
The CCI-400 standard primers gave an average velocity of 3054.40 fps, with a SD of 19.31.
The CCI-41 MilSpec primers gave an average velocity of 3068.90 fps, with a SD of 13.83.
The CCI-450 magnum primers gave an average velocity of 3054.60 fps, with a SD of 11.01.
In this test, the MilSpec primers proved slightly hotter (but only by 14 fps) than either the standard or magnum primers, and the magnum proved to be the most consistent.
As a check of my chronograph under the same weather conditions (mid-60s) I fired 10 rounds of Wolf Gold 55-gr. .223, which averaged 2982.80 fps, SD 28.09, and 10 rounds of Carl Gustav 62-gr LAP 5.56mm, which averaged 2980 fps, SD 12.82.
It would seem to me, that at least with AR-Comp powder, there is little difference between the three types of primer in terms of velocity, and virtually no difference between CCI standard and magnum primers.
FWIW