The idea is to get an objective view of what really transpires in the flame. The temperature reflected is the average that was recorded on the cartridge-neck. Note how fast the temperature rises with each second. When the neck reaches the correct temperature, the heat does not reach dangerous proportions alongside the shaft of the cartridge.
The following cartridges were used:
.223 Remington: Norma
http://flameon.co.za/thermal#sigProIdbbf606e103
.308 Winchester: Lapua
http://flameon.co.za/thermal#sigProId23b1b0d895
.30-06 Springfield: Lapua
http://flameon.co.za/thermal#sigProIdf566e5aa60
.300 Win Mag: Hornady
http://flameon.co.za/thermal#sigProIdccc5d36963
Note: that although the cartridge-neck shows red for temperature purposes, it does not turn "cherry-pink" in reality. If the neck turns "cherry-pink", you are "overcooking" it.
- The correct time is 4 to 5 seconds.
- For the .223 and the .222, the correct time is 3 seconds.