I'm sure a gen-u-wine metallurgist would be unimpressed
Test performed June 2017 at 8:00 am at the Ben Avery Clay Target Center in Phoenix.
Air temperature was 101 and humidity 14%. Haze but bright sunshine.
Guns:12g Benelli Ethos with 1 1/8 oz. 1200 fps factory load.
16g 1906 L.C. Smith 0E "Good 2 Rod" Damascus (used only one barrel for the 25 targets) with 3/4 oz. at 1200 fps reloads.
Barrel steel: Benelli Ethos barrel (likely but unable to confirm on Benelli website) cryogenically treated chrome lined AISI chrome-moly 4140 (Carbon .38% - .43%).
Chemical compositions of 3 Crolle and 1 Twist samples were similar to AISI 1002 – 1005 (Carbon .02% - .05%) low alloy steel by Optical Emission Spectroscopy (OES). This would highly suggest that the iron component was wrought iron (Carbon .05% - .25%) and the steel was (very) low carbon “mild” steel.
Temperatures measured using an infrared thermometer at mid-barrel.
No difference in breech, 15”, or muzzle temps of 16g; 12g muzzle slightly cooler.
Prior to shooting but after guns in rack in full sun for 10 minutes:
Concrete pad Station 1 – 114
16g – 113
12g – 114
AFTER Station 4
16g immediately was 122 but cooled rapidly (in shade) to 112
12g cooled so quickly, also to 112, that unable to record immediate temperature
AFTER Station 8
16g 132 but cooled rapidly to 111 in shade
12g 128 but cooled rapidly to 111 in shade.
After another 25 targets the 12g again cooled rapidly in the shade to 111.
Impression for this non-statistically significant study:
1. No difference in heating between the two barrel steels.
2. The barrels rapidly dissipate heat.
3. Sun exposure contributes to barrel heating.
4. Pain occurs with contact exposure to 111 degrees; 30 seconds of 130 degrees will cause second degree burns to skin.
5. Avoid direct contact with barrels in Phoenix during Hell Season!
