takezoman, the RUM shot very well. However, I have sold it as the smaller cals are doing all I want with way less recoil, noise and costs.
There is little doubt that the ballistics will work way out there. With new bullets like the 210gr Berger and 208gr Amax, plinking beyond a mile is no problem.
If you are just plinking, consider that the 180gr Berger has a higher BC then most any 30cal and 338 bullets. Shooting a 7RM or WSM is SOOO much less cost and recoil vs the RUM.
Then you can also look at the 6.5 which is even more economical.
I try and put on an extreme shoot in the spring and we get all the big cals show up. Out to a mile, there really isn't that much difference from the 6.5 to the 338's for shooting small rocks. The BMG's don't always keep up as the ballistics are there but their mechanical accuracy is not.
For a 30cal plinker, the 300WM is fast becoming my new favorite.
g5m, a friend has a box stock HK SL8. He has enjoyed my stuff so started working up loads with the 75gr Amax and Benchmark. At 1000m/1100yds, this rifle is really accurate.
Our estimated is around 1.5 moa. Your average large pizza box is in serious trouble from consecutive hits. We didn't think it would work that well but after pounding small targets out to 800yds, we just cranked up the scope and went for it.
This is a not a tuned AR with match grade barrel and other tweaks to make it shoot. I fully expect any of the 1/2 min AR's to be very competent at 1000m and further.
All ammo was mag fed. Just looks a little goofy with the bullet seated deep but it works AWESOME. Don't try and overload the ammo. Work up in .1gr and go for best accuracy with smallest vertical dispersion. Test at 200yds.
The biggest hurdle is having enough UP. A Sightron SIII or Mk4 16X has the up you need. Mounted into Burris Sig rings and shimmed as much as possible, I bet you can coax enough up to get out to 1500yds.
Shooting that far with a small cal is WAAYYYY too much fun. I have had all the boomers from 338 down and shot all the way to a BMG. Yes, the power and noise is exciting but the ballistics are such that you pretty much know you are going to connect.
With the 223, you will get tossed around in the wind and doping that is super challenging.
When you get the conditions right and drop that itty bitty bullet on target, you know you have done something.
If you are shooting an AR, you can then just keep tapping that trigger and send fun, fun, fun downrange.
75gr Amax or Berger or 70gr Bergers will get the job done.
Jerry