You are right - it is not logical. My calculator defaulted to 300 yard zero when I recalculated for the .270 and I forgot to change it to 253 yards. Once again, my bad.
That said, the only number that changes is the drop. The corrected drop value of 53.4" is used below.
.270 Win, 150g LRAB @ .591 BC, 7000 ft altitude MPBR zero for 6” target, 600 yards, 2910fps MV:
253 yds = zero point
299 yds = MPBR
53.4" = drop
2209fps - velocity
1626fpe = energy
16.2" = drift
17.7 ft-lbs recoil (8.3lb rifle and scope = Ruger Hawkeye and Burris 3-9x40 FulField II))
7mm RM, 168g LRAB @ .616 B.C., 7000 ft altitude MPBR zero for 6” target, 600 yards, 2900fps MV:
253 yds = zero point
299 yds = MPBR
53.1" = drop
2227fps - velocity
1850fpe = energy
15.5" = drift
24.9 ft-lbs recoil (8.3lb rifle and scope)
27.5 ft-lbs recoil (7.5lb rifle and scope)
So the 7mm RM /168g LRAB DOES have the advantage in drop at 600 yards, by a whopping 0.3". And it wins in drift by 0.7" drift, as I stated before.
But my point remains the same - if both loads are more than adequate for our purposes at 700 yards - using 2000fps and 1500fpe as the benchmark - but our personal limits due to practice restrictions is 600 yards, the additional 23fps and 224fpe at 600 yards is a big "don't care".
For Daughter #1, the disadvantage of the additional 41% recoil of the 7mm load at 2900fps far outweighs its advantages at 600.
For my purposes, the 150g LRAB in my 7mm RM beats the 168g LRAB.
7mm RM, 150g LRAB @ .546 B.C., 7000 ft altitude MPBR zero for 6” target, 600 yards, 3150fps MV:
272 yds = zero point
321 yds = MPBR
543.7" = drop
2357fps - velocity
1851fpe = energy
15.7" = drift
22.5 ft-lbs recoil (8.3lb rifle and scope, 63.0g powder)
I'd go with the 150g LRAB for my 22" .280 Rem as well:
280 Rem, 150g LRAB @ .546 B.C., 7000 ft altitude MPBR zero for 6” target, 600 yards, 2850fps MV:
247 yds = zero point
292 yds = MPBR
58.2" = drop
2106fps - velocity
1478fpe = energy
18.3" = drift
18.5 ft-lbs recoil (8.3lb rifle and scope, 57.0g powder)
Does this mean I'll never hunt with my .338WM or .300WM again? No. It just means that the job I want done can be accomplished with a lot less recoil. Same reason I switched from 160g bullets to 140g bullets in my 7mm RM over a decade ago.
