05-08-2011, 04:13 AM
Mad Max,
It's good to hear that you're using a 30" pipe with 1/9 twist. That will suit you well for the longer bearing surfaces on the 300gr pills. It will also allow you to build pressures with the slow-burning powders to get the velocity you will need to make the 300gr bullets worth it in terms of trajectory and wind deflection advantages over the 250's running faster. One buddy of mine had a custom 30" barrel made for his DTA SRS, and he is using Vihtavuori's next slowest powder up from the .50 BMG powders, which I think is N170. I'll check with him when he's available. He is shooting those 231gr GS Solids at somewhere around 3400 fps, and said there is hardly any recoil. I think he said it only takes him 12 Mils to get to 1600m, which is crazy. He said he has seen no pressure signs at all, so go figure.
If you're really wanting to shoot out to well over 2000 yards, I think turned projectiles are the way to go. I've seen quite a few .338's that maintained their original orientation without nosing over after the maximum ordinate, so they kinda keyhole on targets once they drop through the danger zone, and shed energy faster during that last portion of flight. They were still supersonic and stabilized, but not flying in the most aerodynamic pattern. This was seen on aluminum pop-up targets at 1130m, and some were slightly oriented right or left.
I would probably recommend staying with the 250's going fast for 1000-1400yds, as I've seen them group really well at those distances. Then use the 300gr or solids for reaching into the exploratory realm of .338LM. I'll ask DTA what results they have been getting with the 300's, as well as some other long-range competitive guys that are frequently winning invitational-only matches and have a lot of experience running .338 LM. Be advised, that cartridge will suck down your powder measure really quick...
Back on track with your original post. I really like having the best resolution possible when shooting, so get the best glass you can get, that will hold up to some serious abuse. One thing that I hate with scopes on high magnification is finding the target again if I've adjusted my position or gotten off the gun. The limited FOV on high power really screws you up, so you might want to lean with the largest objective diameter you can get with the best glass if you plan to stay on the higher mag settings. I think USO offers a 58mm objective, and a 35mm tube will give you all the elevation and windage you will need, in addition to an MOA cant mount in the higher tilts (30 & 40 MOA bases).
LRRPF52
It's good to hear that you're using a 30" pipe with 1/9 twist. That will suit you well for the longer bearing surfaces on the 300gr pills. It will also allow you to build pressures with the slow-burning powders to get the velocity you will need to make the 300gr bullets worth it in terms of trajectory and wind deflection advantages over the 250's running faster. One buddy of mine had a custom 30" barrel made for his DTA SRS, and he is using Vihtavuori's next slowest powder up from the .50 BMG powders, which I think is N170. I'll check with him when he's available. He is shooting those 231gr GS Solids at somewhere around 3400 fps, and said there is hardly any recoil. I think he said it only takes him 12 Mils to get to 1600m, which is crazy. He said he has seen no pressure signs at all, so go figure.
If you're really wanting to shoot out to well over 2000 yards, I think turned projectiles are the way to go. I've seen quite a few .338's that maintained their original orientation without nosing over after the maximum ordinate, so they kinda keyhole on targets once they drop through the danger zone, and shed energy faster during that last portion of flight. They were still supersonic and stabilized, but not flying in the most aerodynamic pattern. This was seen on aluminum pop-up targets at 1130m, and some were slightly oriented right or left.
I would probably recommend staying with the 250's going fast for 1000-1400yds, as I've seen them group really well at those distances. Then use the 300gr or solids for reaching into the exploratory realm of .338LM. I'll ask DTA what results they have been getting with the 300's, as well as some other long-range competitive guys that are frequently winning invitational-only matches and have a lot of experience running .338 LM. Be advised, that cartridge will suck down your powder measure really quick...
Back on track with your original post. I really like having the best resolution possible when shooting, so get the best glass you can get, that will hold up to some serious abuse. One thing that I hate with scopes on high magnification is finding the target again if I've adjusted my position or gotten off the gun. The limited FOV on high power really screws you up, so you might want to lean with the largest objective diameter you can get with the best glass if you plan to stay on the higher mag settings. I think USO offers a 58mm objective, and a 35mm tube will give you all the elevation and windage you will need, in addition to an MOA cant mount in the higher tilts (30 & 40 MOA bases).
LRRPF52