09-14-2021, 02:33 PM
These are my results getting started with reloads for my 6 ARC.
My gun. AR Areo upper, lower and BCG. Vltor A5 buffer system with an A5 H1 buffer. LaRue 2 stage trigger with light spring. 22" barrel with +1 gas system made by Compass Lake Engineering from a Criterion 7.5 twist blank.
I started a little high on the charges but wanted to be in the 2700+-25 fps range.
Powder was Leverevolution and bullets seated .030 off the lands (CBTO 1.679 COAL 2.254) on the 108 ELD-Ms
Measurements were with the Hornady head space comparator #350 and bullet comparator #324
Temp. was around 90 and humidity was Florida ?
First 5 shots were with Hornady factory Black 105gr to get a baseline and warm the barrel and check function of chrono.
Charge Avg ES SD Group size
Black 2780 17 5 1.1
108 reloads
28.8 2673 42 15 .81
29.0 2693 40 19 1.3 but I pulled 1 shot .81 without that
29.2 2710 51 21 1.53
29.4 2732 25 9 .98
I loaded a few (10) rounds of 109gr berger LRHT mostly to function test
29.0 2675 59 25 1.84 .051 off the lands
29.2 2687 44 16 1.50 .045 off the lands
Primers looked great and only very slight ejector marks in all but the lightest load.
I measured and took apart a factory 105 Black when I got home but haven't checked jam/jump length yet. I weighed the powder that "appears" to be lever and got a weight of 29.9
That's all folks
My gun. AR Areo upper, lower and BCG. Vltor A5 buffer system with an A5 H1 buffer. LaRue 2 stage trigger with light spring. 22" barrel with +1 gas system made by Compass Lake Engineering from a Criterion 7.5 twist blank.
I started a little high on the charges but wanted to be in the 2700+-25 fps range.
Powder was Leverevolution and bullets seated .030 off the lands (CBTO 1.679 COAL 2.254) on the 108 ELD-Ms
Measurements were with the Hornady head space comparator #350 and bullet comparator #324
Temp. was around 90 and humidity was Florida ?
First 5 shots were with Hornady factory Black 105gr to get a baseline and warm the barrel and check function of chrono.
Charge Avg ES SD Group size
Black 2780 17 5 1.1
108 reloads
28.8 2673 42 15 .81
29.0 2693 40 19 1.3 but I pulled 1 shot .81 without that
29.2 2710 51 21 1.53
29.4 2732 25 9 .98
I loaded a few (10) rounds of 109gr berger LRHT mostly to function test
29.0 2675 59 25 1.84 .051 off the lands
29.2 2687 44 16 1.50 .045 off the lands
Primers looked great and only very slight ejector marks in all but the lightest load.
I measured and took apart a factory 105 Black when I got home but haven't checked jam/jump length yet. I weighed the powder that "appears" to be lever and got a weight of 29.9
That's all folks