How accurate is my rifle

[Drifter]

Drifter:

To be up front, I view all the stuff about 'cold bore' zeros to be more myth than fact. I believe the majority of variance from a zero is due to the shooter firing his first shot of that day, with all the baggage he takes to that shot.

If the barrel sucks, it will suck dirty or clean no matter the bullet. If the bullet sucks, it won't get better because the barrel is dirty, hot, or cold. This is because bullets that suck are generally not balanced well and a dirty or warm barrel won't change how the bullet was made.

Also, I haven't seen any indication that such a thing exists with barrels or ammunition ranging from service through match grade. I have seen hundreds of pages of 'cold bore' shot records and haven't seen a pattern that anyone can predict.

Finally, one shot won't change barrel temperature enough to have any meaning and one shot won't put enough fowling down the barrel to change anything, either.

What heat, cold, or humidity may do is cause problems between a receiver and a wooden stock which in turn may cause zero problems.

LR55

I use "cold-bore" as a general term, as I don't really think barrel heat is the culprit in my particular case. I think the issue lies mostly with copper fouling, where as bonded bullets seem noticeably worse regarding first-shot fliers from a barrel left fouled with the same bullet (which pertains to hunting applications).

I shoot almost every day with few exceptions. I've shot my entire life, but for the last couple of years, I probably average at least 4 days per week shooting, almost exclusively 6.5 AR's (Grendel and Creedmoor), with some 5.56 and 7.62x39 mixed in once in a while. When it's not hunting season, I might make 3 range trips in a day (600-yard private range 3 miles from home). I've tested a lot a 6.5 bullets in various barrels (3 Saterns, 2 Sabre Defence, 1 Krieger, 1 BHW, and 1 Criterion), and stick to my belief that not all bullets behave the same with the very first "cold-bore" shot, regardless of which weapon a session begins with.