I've read that barrel break-in is necessary, not necessary and not always necessary. Great. With regard to barrel break-in as a general subject I am a bit skeptical that it's needed as much today as it may have been in the past. Why do we think we need to break in barrels? It's to lessen, smooth, eliminate internal tooling marks so stuff like copper & lead don't snag on them. Modern tooling is just so superb that it just doesn't leave much left to "hook" copper & lead. That said, I also think tooling marks depend on the barrel's manufacture. (How's that for talking both sides at once. ) Krieger makes what are arguably the finest barrels anywhere and they DO recommend barrel break-in. REF: https://kriegerbarrels.com/faq#breakin. Blaser barrels according the instruction manual are cold forged. Krieger barrels are cut. To further confuse matters, years ago I was told that barrels made by Miroku (for Browning) have a very fine grit-slurry forced through their barrels under high pressure after manufacture to remove any tooling marks. I don't know if this is/was true of ALL their barrels. The manual for my Blaser R8 says nothing about barrel break in. All they say is to clean it "after it has been fired". The latest Blaser R8 manual is available at Blaser's website. https://www.blaser.de/en/services/infomaterial/user-manuals/ There's a serious question coming...I promise. All I ever did was to make sure the barrel was clean before the first shot and then,partly out of superstition, clean the barrel after 3 shots, 2-3 times. That's it. I have never seen or read a scientific study of barrel look & performance before a break in vs. not. I suspect you would also need a fairly sophisticated bore scope to see if breaking in is even necessary and how it looked after the so-called break in. Here's the serious question: What would the difference in break in requirements be, if any, for barrels manufactured with these two radically different processes: cut vs. cold forged? I always wondered.