While I was waiting for my rem mag to cool between groups yesterday I shot my 223 bolt gun. I have a low pressure Varget load that shoots pretty good and an IMR 8208 XBR load that is .3 grains below pressure signs that shoots lights out. I usually shoot the Varget load and reserve the XBR for serious target work, which for me is not that often. I'm an experienced shooter and reloader and shoot a good bit. I'm also fairly new to this site. It appears there is a lot of knowledge and experience here. Particularly shooters that take it a lot more serious than me.
On to my question: would you roll with the high pressure load full time and not worry about a shorter barrel life and a load that had its back to the wall, or go easy on a sweet shooting little varmint gun and save the high pressure load for times you are serious about it? How does the brain trust weigh in?

I shot Varget out of it for the most part yesterday, but did shoot a three shot group with the XBR. I just learned how to post pics and there are some targets still in my range bag. I will mark up a couple targets and take a couple pics.

How far are you shooting? 100 yards - roll with the light load. Past 300-400 yards - I'd probably shoot the faster stuff.

Either way - nice shooting!

I shoot coyotes with it mostly and pop a couple does in the bean each year. It is a light sporter that I usually shoot 55 grain bullets at 300 and closer.

Out of a 223, I wouldn't worry too much about it. Run whichever you like for that application. 223's have decent barrel life already, so a hotter load would be fine.

To the OP's direct question, higher velocities + higher pressures. Can't have one without the other. Higher pressures = shorter barrel life.

Don't remember exactly but read once that barrel life can be calculated by the amount of powder put thru it. Has a lot to do with heat and how hot for how long at a time. Every time you pull the trigger you are in essence putting a plasma torch down the barrel for a microsecond.