Jordan Smith has witnessed the phenomenon in match grade barrels and not in ordinary factory barrels, while burchlambert1 has seen very little effect in custom barrels, and Mule Deer has seen no effect.
I join the crew that has never ever seen any effect in any kind of barrel.
For me, it is hard to believe that some microscopic changes in the barrel dimensions can have such an effect in the powder pressure burning curve that could translate into 100 or 150 fps difference.
Which is quite a lot. To put it in perspective, Winchester factory 130gr loads for the 270WSM are fps faster than the WSM.
I am now in the process of shooting with a new barrel which following's Mule Deer breaking in process of a thorough cleaning every range session and not every one, or, three and then five, shots, has already gone through 53 shots and two cleanings.
My favourite load so far, has lost .according to my Lab Radar, 10 fps from the first session to the third. I am right thinking it will now have to regain 110-160 instead of the original 100-150 that seems to be the norm?
Ain,t that funny?
Alvaro
Last edited by chamois; 03/14/21. Reason: to correct sentence construction mistakes
