I have tried this recipe a few times, with less than spectacular results. It calls for 25.3 grains Varget, C.O.A.L of 2.60.
Listed performance is 2750 fps and 1158 Ft. Lbs. Firearm used for their testing is Colt AR 15-15A2 HBAR, 20" barrel with 1/7 twist. Trim length of 1.75, and Rem 7 1/2 primer.
My rifle uses a 18" Ballistic Advantage SPR barrel, allegedly "guaranteed" for 1/2 MOA, 1/7 twist.
I used LC brass, trimmed to 1.75. I used the stated load of Varget, seated the 69 grain SMK to the stated 2.260". Primer was CCI nato #41.
They were hard pressed to do1.5 MOA (100yards) which included 3 separate range trips with excellent weather conditions.
At the same time, I loaded Sierra 52 and 53 grain MK, with 26.7 and 27 grains Varget at 2.250 (as recommended by Sierra in the same article) with MUCH better results.
For what its worth, Sierra's reccomended "accuracy" load for these 2 bullets was Viht. N133, 23.5 grains, yielding 2900 fps and 989 ft lbs.
They listed my Varget loads at 2900-3000 fps, 989-1059 ft lbs.
Any ideas as to why my 69 grain loads are not working well in my gun? I thought I might load a few a little hotter, they list a 25.7 grain load, and a max load @26.1 grains. Going the other way, there are cooler loads, 23.3 minimum, 24.1, and 24.9 as well.
Thoughts?
Russellc
Listed performance is 2750 fps and 1158 Ft. Lbs. Firearm used for their testing is Colt AR 15-15A2 HBAR, 20" barrel with 1/7 twist. Trim length of 1.75, and Rem 7 1/2 primer.
My rifle uses a 18" Ballistic Advantage SPR barrel, allegedly "guaranteed" for 1/2 MOA, 1/7 twist.
I used LC brass, trimmed to 1.75. I used the stated load of Varget, seated the 69 grain SMK to the stated 2.260". Primer was CCI nato #41.
They were hard pressed to do1.5 MOA (100yards) which included 3 separate range trips with excellent weather conditions.
At the same time, I loaded Sierra 52 and 53 grain MK, with 26.7 and 27 grains Varget at 2.250 (as recommended by Sierra in the same article) with MUCH better results.
For what its worth, Sierra's reccomended "accuracy" load for these 2 bullets was Viht. N133, 23.5 grains, yielding 2900 fps and 989 ft lbs.
They listed my Varget loads at 2900-3000 fps, 989-1059 ft lbs.
Any ideas as to why my 69 grain loads are not working well in my gun? I thought I might load a few a little hotter, they list a 25.7 grain load, and a max load @26.1 grains. Going the other way, there are cooler loads, 23.3 minimum, 24.1, and 24.9 as well.
Thoughts?
Russellc