I have a friend who is an experienced handloader, retired local swat sniper, load up some 6mm arc for my bolt gun.
We are using once fired Hornady brass (not annealed), CCI 450, Hornady 105 gr Match and Leverevolution. Loaded to factory length using Wilson full length sizing die.
The attached 10 round group is 29.2 grain charge weight. Hole 9 & 10 the bolt was heavier than normal when opening and closing. 6 & 7 I’m confident were my fault. If I remove these four shots it’s about a 1/3 moa group. At the start of the session I shoot 1/2” groups with Hornady Black 105 so I’m confident in my fundamentals, ability to call the shot and gear.
Below are the velocities. ES 68 and SD 16. Both are obviously too high.
2900
2909
2861
2889
2881
2887
2881
2881
2929 (heavy bolt)
2908 (heavy bolt)
Is the heavy bolt due to improperly sized brass?
For my purposes a group 1/2” or less is fine.
Any recommendations on how to move forward?
Friend wants to try 29.0 and 29.4.
We are using once fired Hornady brass (not annealed), CCI 450, Hornady 105 gr Match and Leverevolution. Loaded to factory length using Wilson full length sizing die.
The attached 10 round group is 29.2 grain charge weight. Hole 9 & 10 the bolt was heavier than normal when opening and closing. 6 & 7 I’m confident were my fault. If I remove these four shots it’s about a 1/3 moa group. At the start of the session I shoot 1/2” groups with Hornady Black 105 so I’m confident in my fundamentals, ability to call the shot and gear.
Below are the velocities. ES 68 and SD 16. Both are obviously too high.
2900
2909
2861
2889
2881
2887
2881
2881
2929 (heavy bolt)
2908 (heavy bolt)
Is the heavy bolt due to improperly sized brass?
For my purposes a group 1/2” or less is fine.
Any recommendations on how to move forward?
Friend wants to try 29.0 and 29.4.