I’ve been using wolf in my MP5 clones for a few years now. Pistol caliber barrels don’t wear nearly as much as a rifle barrel would. I’m about 20,000 rounds without any noticeable wear. Most of, but not all have been in full auto. I did get a off batch of underpowered 9mm rounds about 3 years ago, but their ammo has been pretty consistent with the powder charge. Last batch I bought a few months ago was 13 cents per round.