Nate,
you damage your barrel every time you pull the trigger. That's kinda the point. They're threaded on one end, and noting more than a piece of perishable tooling that's temporarily attached to your receiver. They wear out, and you replace them, simple as that. The option to get around that is simply not to use them. You use it, you damage it, and eventually it wears out.
There are some things that will be harder on barrels than others. Heavy bullets are a big one, and will wash out the throat a lot faster than lighter bullets will. Excessively high pressure loads are another. Most modern powders aren't too bad about temperature, but in the old days, very high nitroglycerine content in some powders positively ate barrels for breakfast. When the M1903 Springfield was adopted, it was originally loaded with a 220 grain FMJ-RN, loaded with Hi-Vel #2. This combination (heavy bullet, high nitro content) left those barrels shot out in about 800 rounds. You don't see that today, with a well balanced cartridge and sensible loads. Rapid fire isn't the boogeyman that most shooters today make it out to be. As I mentioned, in Infantry Trophy matches, we fire (on average) 30-40 rounds in about 50 seconds, at a couple of yard lines. The barrels last just fine, and accuracy isn't an issue. I've seen the gunners at Lake City doing M118LR testing, and those guys generally go through a ten round string in a matter of seconds. Literally sounds like a machinegun. They're firing a return to battery rest, an virtually pouring the rounds into the mag as they cycle the bolt. They generally repeat this process for about three groups before they switch out, and the barrels are way too hot to touch. They still shoot, and they get a respectable service life out of their barrels. Not suggesting anyone abuse their barrels, but don't be afraid to use them, either. After all, that's why we have them.
