I was inspired by questions raised in this thread: .308 Bullet Weight effects past 1,000 Yds
My basic premise- would i trust a 308 for man sized targets at 1500 yards? cold bore hits are priority, overall ability to make life difficult for a bad guy at 1500 secondary.
I'll start with conditions- about perfect. It was 40F, barometer said 30.15, 53% humidity, 2-5 mph winds, clear, sunny, cold- aka heaven.
I want to thank MontanaMarine for a few things- the load, the time, the preparation of the course (torture, right?), and for being an all around great guy to shoot with.
here are the rigs (and MontanaMarine's custom tactical shooting mat...)
my Tikka varmint 308 in a Mountain Tactical thumbhole tactical prototype, 20 moa rail, 10x SS, harris 6-9 swivels, duct tape & foam cheek. I modded the bolt stop & mag to feed 3.004" cases (still need to do something about the tilting follower, but Jason's on it- right Jason?). My loads are copied from MontanaMarine all the way- 48.5 gr R-17 under 208 amax's at 3.004" COAL
MontanaMarine's 30-06- i"ll let him fill in the details, because i'd likely get them wrong...
I recently switched triggers, so i took a 'zero check' shot at 100 & made my 3 clicks left to get it back to zero. Then i let it cool so i could honestly approach this from a cold bore perspective.
OK, we didn't have an actual 1500 yard target lined out, so MontanaMarine suggested that since he had a mile target already verified, why not just start there & work on the 1500 yard target after. Seemed like a good idea to me.
I'm a little sleep deprived (thanks to my 3 year old) & don't remember what MontanaMarine's first string looked like- sorry, man, you gotta fill that in, too. I do remember his first shot being low (and later realizing that his rifle was zeroed ~1"-1 1/2" low at 100), and we had some difficulty getting good splash to call hits & misses. We moved from the original .5 mil rock to a slightly smaller bush to its left & got good dust for spotting shots. Accuracy was better than I expected for a 30-06 at a mile.
Now we had a dependable target for spotting shots, so I slithered up to my 308 & consulted Shooter. My scope cap dope chart ends at 1500- which will be fixed soon ;) , so i went with the app.
1) I dialed 24.6 mils, & held left edge. First shot, cold bore- missed 1 mil low & .5 mil right.
2) held 1 mil up & .3 left- missed .5 right of target- elevation was on target, but lowish
3) held 1.2 mil up & .5 left- missed .2 mil right, good elevation
4) held 1.2 mil up & .7 left- hit at 3 o'clock on the edge
5) held 1.2 mil up & 1 mil left- hit near center
You could say that i was encouraged...
Our solution to not having a 1500 yard target was to move 260 yards closer to the mile target. The light had changed enough that we weren't getting good spots on MontanaMarine's first string at the bush from the mile setup, so I gotta ask you to fill in the details again... I should have kept notes on both...
My dope card goes to 1500, and has been verified out to 1200, so i was more confident about the 1500 yard round.
Atmospherics: 4330ft, 45F, 30.12, 56% humidity
I dialed 19 mils & fired- the first string of 5 was difficult to spot- we both think i hit most of them, but decided to shoot the original .5 mil rock that wasn't showing splash earlier. It was all good now. Of course, he had to go & shoot a chunk off of the right edge & make it smaller for me, but I didn't mind.
second string- much better visibility for calling hits & misses
1) held .5 right- missed .3 off right edge at 3 o'clock
2) held top third- hit, center
3) held center- hit 7 o'clock edge
4) held center- hit 4 o'clock edge
5) held top center- hit 12 o'clock on the top edge of the rock (double splash)
My 2 cents- if I could take handloads (or Mexican match some 208's into the mix somehow on deployment), I would feel pretty darned cocky with my little 308 taking 1500 yard shots.