I will be the first to admit that there was not much logic to my point. I just really love the 'romance', if you will, of the old African calibers and I would love to hunt with them. In the same way, I'd like to hunt with a double. However, I recognize that logically, the R8 with appropriate barrels makes far more sense financially and logistically. If I exclusively went with an R8, I would probably take .30/06, 9.3x62 and either .416 Rem or .458 Lott barrels myself but to each his own.
At this point, I have a very large trial coming up in September and October. Usually with a big trial, I will get myself something at the conclusion. In the past, that's been a couple of 10mm pistols, or a good saltwater rod/reel combo (Scott Centric 12 wt with a Mako reel if you're interested), or something else. I'm leaning toward using this trial as an excuse to get an R8 but I haven't decided. I still owe my favorite Uncle a fair bit so we will see how much is left over when I pay him.
I do have a couple of questions, though: how hard is it to change barrels on the R8? Let's say you're looking for PG, impala, bushbuck, nyala. Something for which you'd use a medium bore so you have say a .300Wby barrel on your R8. If you come across good buff track and you decide to follow the buff, would it take long to change the barrel there in the field? Or is that something that realistically is done at camp?
Also, do you have the .22LR barrel for practice? If so, what do you think of it?
Interesting question, that has been the topic of hot debates amongst R8 aficionados and non-believers alike...
First, the technical facts...
It takes honestly about 1 minute to change a R8 barrel in the field. Add about 1 minute if you need to attach a scope to it, add another 2 minutes if you need to change the bolt head, and also add 1 minute to change the magazine insert of the trigger group. I know this very well because I have done many barrel changes at my field shooting range when I was sighting the various barrels/scopes of my R8, as well as those of my wife's R8. It is actually so easy and they return so reliably to zero, that I even got into the habit of alternating between barrels when testing loads to cool the barrels. So, technically, the answer is GO.
Second, hunting reality in modern Africa...
There are two scenarios: change barrels at the truck in between morning and afternoon hunts; and change barrels during a hunt.
As to changing barrels during a hunt, as I have stated several times in discussions regarding this topic, it is a rare situation indeed in modern Africa when you would have the opportunity to take an opportunistic shot a Buffalo (or Lion, or Elephant, i.e. dangerous game), while hunting plains game. The reality is that Lion, Elephant, or even Buffalo hunting have become so specialized, licenses so rare, and trophy fees so expensive, that if you have one of them on license, you will most likely hunt it with single minded focus and the appropriate caliber, and if you do not have one on license, or cannot afford one, you will not be able to shoot one if you stumble upon one.
In addition, at least to me, carrying in the field a second barrel, second magazine insert, second bolt head, second scope, second ammo caliber, and attempting to reconfigure a R8 on the spoor seems totally unrealistic, never mind the chances of loosing a smaller component such as magazine insert or bolt head. I have never done it and do not intend to ever try.
The different scenario that I have done, is to carry all day, days on end, the double .470 on Buffalo, Lion and Elephant spoor, and asked a tracker to carry my scoped R8 in case a longer shot is presented. Actually, I have shot both Elephant and Lion with the scoped R8, because in both cases the shot came late in the hunt and late in the day, and it was on the longish side for a double. But all I had to do was switch rifles, not barrels, and all it took was mere seconds, and this is not the scenario we are discussing in your question.
As to changing barrels at the truck between hunts, things are different. If you are organized and methodical in planning your hunt, and your day pack includes a second barrel, scope, magazine insert, bolt head, ammo slide, and Blaser hex wrench, I see no reason why not.
Because of the calibers I shoot, I have actually never done it myself, and interestingly all the PG animals you mentioned: impala, bushbuck, nyala I hunt with the .257 Wby barrel, not the .300 Wby. The .300 Wby goes on for the next class of animals: Kudu, Wildebeests, etc. In truth, more and more I hardly use the .300 Wby barrel because the .257 Wby with 100 gr TTSX has proved so lethal all the way to Roan, that I feel confident using it on darn near anything short of Eland. Of course, if I was going purposefully after a monster Sable or Roan, I would plan to use the .300 but my default barrel is the .257 Wby.
The only times I have changed R8 barrels during the day in Africa were back at camp. One time, getting ready to go for a night hunt after Bushpig on bait when I wanted raw power to anchor it; and one time getting ready to go for a late afternoon ambush of a specific Kudu that had eluded us for days, and when I knew that the shot would be long and I needed bullet mass to deliver the killing way out there. In both cases I used the .300 Wby barrel and it paid off...
Otherwise, I typically keep the same barrel days after days until the animal I hunt is in the salt, but admittedly, all the R8 calibers I use in Africa: .257 Wby, .300 Wby, .375 H&H, .458 Lott have 200 yards reach, which allows me to capture the opportunity if the next world record three-toed unicorn steps out off a bush while I hunt something else. And admittedly too I have been lucky to go several times and to collect good heads of most PG species - except those of East Africa, therefore I typically hunt very specifically for specific animals, and I am quite happy not to shoot if we cannot connect with the one we are after, therefore opportunity shots are rare for me.
Regarding training, I have written also extensively about this on AH. In summary, I am a very strong proponent of small caliber practice and have burnt literally 10,000+ .22 LR rounds learning to shoot from the sticks. Nonetheless, my R8 practice barrel is a .223, and my wife's is a .222, because we live in the Western US and it is so easy to find 300 yards, and longer, shooting spots on public land. The .223 and .222 give us the opportunity to practice out to 300 yards, the .22 LR does not. Yes, I have practiced for years shooting at 100 yards with the .22 LR on smaller steel plates, with arching trajectories, but the instant the wind picks up, the .22 LR is out of its league at anything past 50 yards, and there is a lot of wind on the high plateaus of the Western US. I had to scale up to .223 to deal with this, but if I was still living in the Eastern US or Europe, my R8 training barrel would be a .22 LR...
