Cold Bore fliers

Idaho Lefty hit the nail on the head, in my experience....quality barrels eliminate issues. I clean and degrease like Hugnot. I can not recall a Hart, Krieger, Brux, Muller barrel that threw Radical shots on the first cold bore shot in properly bedded stocks, and I run a muzzle break on every rifle, twisted properly. The rifles all shoot tiny groups. A first shot out of the clean barrel will usually be .3 out of the group, but if were to throw a shot 1.5" out, that barrel would be scrapped.

I fire three shots on a squeeeeky clean bore prior to hunting as a matter of good gun handling practice.

Much of the "thrown" shots that NON competitive shooters experience is from having too much coffee or just not being settled down. I was advised to sit at the bench and observe wind conditions prior to firing for five minutes(heart rate will settle down), then when I get on the gun, I dry fire several times aiming at the target as if I were firing a group, watching where cross hair ends up after the shot(follow through). My shooting improved significantly when using this discipline.

A very experienced Long Range gunsmith(now passed on) advised me that contours smaller than a #5 are prone to more "issues".

When a load is out of "tune", expect all kinds of issues, same thing with bullets of suspect quality.
I agree with this; quality barrels put the first shot right in there. My guess is a lot of guys who have flyers haven't removed residual solvent, oil, grease, or whatever they last put in the barrel.
Very fouled barrels are unpredictable. If you can look in the muzzle and see copper streaks, then it is time to start scrubbing.

One of the things I do with a barrel is to determine the cleaning frequency before groups start to open at peak accuracy....can of worms.