Barrel wear has NOTHING to do with the size/weight of the projectile. NOTHING.
It has everything to do with the amount of powder capacity compared to the bore size.
For example, and I speak from long term serious first hand experience, my 300 Winchester Magnum DOES NOT wear the barrel anywhere near the rate that my old 220 Swift did. It is not even close. And my 300 Winchester Magnum uses 74.5 grains of slow magnum powder behind a .308 diameter 168 grain bullet, compared to the little .223 diameter 50 grain bullet in the 220 Swift with about 40 grains of the same powder.
Now, if you step up to 300 Kong(AKA 300-378 or 308-378) or something along that order, you'll find the powder capacity in relation to the bore size is more closely comparable to the 220 Swift. Those rifles WILL wear a barrel like a 220 Swift.
The OLD chrome moly barrels from a few decades back were not as hard as the barrels today are, the heat treat is different. Never mind the fact that stainless steel has become the choice for serious overbored high velocity rifles.
It isn't even the speed difference. Again, using MY rifles as an example, the 300 Winchester pushes its 168 grain bullet around 3200 FPS, where the old 220 Swift, before I ruined it, pushed a 50 grain bullet to nearly 4200 FPS. But it was the powder burning that killed the 220 Swift, because you shoot the THROAT out, not the muzzle where the bullet is fastest.
My 300 Winchester Magnum has over 2000 rounds through it, and the throat looks great. The problem is there is now a rust spot near the muzzle where a relative borrowed it and failed to oil and clean it. It still shoots sub MOA groups, but not as consistently. So it's getting a new Douglas air gapped premium 26" number 5 taper barrel.
The 220 Swift is another story. At around 1000 rounds, I noticed the accuracy was falling off, and the bullet drop was growing at long range. So I took a chronograph and checked my velocity. Finding it off about 150 FPS, I decided I'd bump the load up a little, as I'd moved to a new lot of powder. So, I did. Next time I shot, I began to notice serious pressure signs. They were not real danger signs, but pressure had gone up. Back to the chronograph. Uh oh, I only got 40 FPS back. A complete disassembly and inspection showed serious throat wear. Cause? I had been fooling around shooting crows and varmints, and firing the gun way too many times per hour. Talking to an old gunsmith, he explained EXACTLY what I'd done by looking at the rifle BEFORE I told him anything, and then he told me how the rifle was shooting, BEFORE I told him. heating the barrel up softened the steel, and the heavy overbore charge had eroded the throat, I had literally shot the barrel out.
I have fired the 300 Winchester as fast, or even faster, than the 220 Swift. The throat is fine. You can do the same thing as I did to the 220 Swift, to a 22-250, as the powder capacity is close, with the 220 Swift on average about 150 FPS faster than a 22-250. I have even seen 223 Remingtons with the throat shot out, when doing rapid fire target shooting, or shooting varmints in locations like a prarie dog town.
These days, barrel steel is better, especially the stainless steels, and so long as you are smarter than I was, a 220 Swift or a 22-250 will last forever, properly loaded and maintained.
Since the chamber diameter is pretty much the same regardless of the barrels style or taper (the diameter of the chamber end of the barrel is determined by the action, you have to have the right diameter to screw into the action), barrel weight/taper does not have as much to do with barrel wear as you might imagine. You MIGHT be able to make the case that a straight taper barrel is a better heat sink. But the diameter at the end of the chamber and the throat will be close to the same regardless of the taper, because of where the taper starts. The reason bench rest shooters use heavy straight taper barrels isn't wear, it is stiffness.
Certain types of powder will make the wear problem worse as well. And the slower the powder the worse the wear.
The reason you don't see it too much in the M-16/AR-15 family as the popularity of chrome lined barrels on those rifles.
We use 44 Magnum and 45 Colt lever guns on brown and black bear (mostly black bear) around here (we often use handguns on both bear and boar). We've looked at going to Alaska to hunt really BIG bear, like Kodiak. If we go, I'll likely get a 50 Alaskan lever gun. I prefer large heavy bullets at medium velocity for use on really big game, because they break large bones and continue to penetrate. I'm not that big on 458 Winchester or those type rounds, and I really don't like larger bolt guns for that type hunting. I'd much rather have a fast handling 50 caliber lever gun with 5-7 rounds than a slower bolt gun with 3.
