@ 08:12 am (GMT)
Nathan FosterHi Scott, the actual switch barrel concept can be hit and miss, especially in these environments.
Yes, I know its popular these days, especially in tactical rifles- but so are bubble levels mounted in places where they are of no use.
A major problem with switch barrels, is that in order to be able to make the switch, the barrel threads need to be loose enough that they can be undone by hand, often using a grub screw as a retainer. The trouble with this is that changes in temp can allow the system to loosen just a fraction, either opening up groups or causing double grouping. This can be offset by bedding the first couple of inches of the barrel channel but the trouble is, the bedding will only suit the one barrel.
Then comes the annoyance of the switch where the rifle has to be re-zeroed each time and where changing scopes is not as plain sailing as it might have initially seemed in light of other factiors.
Some of the heavier switch systems work well but the rifles are not well designed ergonomically. The Desert Tech is a good example of this, quite solid in design, locks ups well, but is a mongrel to carry any distance in its current design guise.
The cartridges you mention also yield some cross over. The man with an accurate .30-06 AI loaded with projectiles capable of producing clean kills on all manner of game out to 800 yards or so has no need for a .25 and will eventually tire of it. The .338-06 has merit but its not a major step up in power over the .30-06, only penetration with conventional soft point projectiles. Change the projectile in the .30-06 and you will change the dynamics. If only each of you could understand just how versatile the .30-06 really is simply by changing projectiles rather than barrels. If you settled on the .30-06 AI only, then waited and saved for a .375 Ruger, you might find this combination to be highly rewarding.
Sorry, I know this is not the answer you were hoping to hear. However if I am to help, I need to be able to explain some of the pitfalls of switch barrel rigs, plus the possible waste in time and funds doubling up on cartridges. The first step is to understand the projectiles rather than the cartridges. Also, in my cartridges book, I would suggest that you refer to the throating section within the .30-06 section. Your M1999 has plenty of mag length and if you combine you AI blow out with the longer OAL, the cartridge will very easily equal the .300 WSM.
Food for thought. All the best.