Not trying to defend Bob (who needs no defense), but as an unabashed 30-06 admirer I will say I have some buddies who convinced me to try the 7 MSM. I thought about it for a good while, because I have now two exceptional 30-06 rifles (that would have served me well for years to come), and the reason I was convinced to try the MSM boils down to a difference of 100 yards.
I use a Leupold 6x42 LRD on my primary 30-06. I sight the rifle in with either 165 or 180 grain bullets, moving at 2900 and 2800 fps respectively. I choose a sight-in distance such that the bullet doesn't more than 3 inches high at MPBR. For my 30-06 that means about 215 yards, and the bullet is 3 inches low about 275 or 280 yards away. Then the first dot of the LRD is about 300 yards, the second about 400 yards.
I can sight in the 7 MSM, with a 160 AB moving about 3200 fps, with the same 3-inch trajectory consideration, at 250 yards. I need to move to the first dot around 375 yards, and the second dot gets me to almost 500 yards. Some of this advantage is the starting velocity 300-400 fps faster than the 30-06. Some is the BC of the 7 mm bullets available.
The 280 AI and 7 Rem Mag use the same bullets as the MSM, but lack the extra velocity. The bottom line is I don't think they provide enough advantage to dedicate another keg of powder (because a new chambering for me means another keg of powder--I don't like to [bleep] around with too many powders) to my stores. But a 100 yard advantage out west hunting elk--that's a reason to give the MSM a spot in the gun safe. And my bigger than life buddy tells me the recoil won't be unmanageable...
...and I became introduced to a rifle that just happened to be chambered already in a custom quality Remington 700 package, complete with already chambered spare Lilja barrel.
