Help wanted: 7MM WSM
I am a newbie to LRH and reloading. I received my custom 7MM WSM in September. It has a Krieger #5 barrel finished to 22” on a 700 frame. Initially, I was shooting Winchester Extreme 160 gn. XP-3 ammo. The XP-3 ammo was off the lands about .200. Although the box indicated a muzzle velocity of 3050 I was getting 3100 but not the accuracy I was looking for. I have finally accumulated reloading equipment and have tested several loads. I’m starting with 162 gn Hornaday A-Max bullets, New Winchester brass neck turned and trimmed, Primer pockets cleaned and deburred based on information from this site and others. Using WLR primers and setting the OAL (2.985) for .003 off the lands. I thought I would start with this length and after arriving at the best powder configuration start working to shorten the OAL and see the effect. The outside neck diameter is .311 before loading and is .3125 with the bullet seated. After firing the neck diameter is .3175. These load components were based on R. Horst’s hunting load recommendations from the 6mmbr web site. With the 162 gn A-Max and 64.0 gn. Of H4831sc and WLR primers and a 1 in 9 barrel he was getting a muzzle velocity of 2950. I have no idea what his barrel length was. With 62 gn. I am getting a MV of 2650, 62.5 MV 2700, 63.0 MV 2740, 63.5 MV 2795 and 64 MV is similar to 63.5. I’m at a loss for why my rifle had higher velocities with the factory ammo and less than expected from the reloads. I had intended to find the combination for a MV of 2950. Where do I go from here?
I am a newbie to LRH and reloading. I received my custom 7MM WSM in September. It has a Krieger #5 barrel finished to 22” on a 700 frame. Initially, I was shooting Winchester Extreme 160 gn. XP-3 ammo. The XP-3 ammo was off the lands about .200. Although the box indicated a muzzle velocity of 3050 I was getting 3100 but not the accuracy I was looking for. I have finally accumulated reloading equipment and have tested several loads. I’m starting with 162 gn Hornaday A-Max bullets, New Winchester brass neck turned and trimmed, Primer pockets cleaned and deburred based on information from this site and others. Using WLR primers and setting the OAL (2.985) for .003 off the lands. I thought I would start with this length and after arriving at the best powder configuration start working to shorten the OAL and see the effect. The outside neck diameter is .311 before loading and is .3125 with the bullet seated. After firing the neck diameter is .3175. These load components were based on R. Horst’s hunting load recommendations from the 6mmbr web site. With the 162 gn A-Max and 64.0 gn. Of H4831sc and WLR primers and a 1 in 9 barrel he was getting a muzzle velocity of 2950. I have no idea what his barrel length was. With 62 gn. I am getting a MV of 2650, 62.5 MV 2700, 63.0 MV 2740, 63.5 MV 2795 and 64 MV is similar to 63.5. I’m at a loss for why my rifle had higher velocities with the factory ammo and less than expected from the reloads. I had intended to find the combination for a MV of 2950. Where do I go from here?
