Quote Originally Posted by Texas10 View Post
In another study, Dan, and if I can find it I'll attach it later, was a check of velocity as compared to barrel temp. IIRC, the procedure was to place a cartridge in the magazine (as you do) and then chamber and fire as quickly as practicable, measuring velocity spreads as the barrel warms. The study concluded that it was barrel temp, not cartridge temp that caused velocity spreads and that the amount of time a cartridge typically spends in the warm/hot chamber was not enough to effect powder/primer burn rates.
If I understand this principal correctly, a hotter barrel has less of a quenching effect upon the expanding gas than a cool barrel, resulting in increased velocity.

Personally, my practice is to do as you. Load and fire, usually in less than 30 seconds. I have also used an IR thermometer to track and record barrel temp vs POI and found that my fluted barrel really starts to move at about 100 F and above.

So glad autumn has finally arrived here in South Central Texas!
Great info Texan!