I have a few pounds of BL C2 and am about to start shooting my 308 again. I know it works very well in warm weather, but I seem to remember hearing that it's somewhat temperature sensitive. Anyone have any experience with this powder in cool weather?
BL C2 in cold weather
- Thread starter Papaclaude
- Start date
Yup. I use BLC2 in a few loads as well. I believe all powders except the "extreme" series have some degree of temperature sensitivity. From actual shooting experience at the range I can say that within sane hunting distance (200 yards and under) you will not likely notice any difference. Use magnum primers for ball powder in cold weather for sure.
The key is to set the thermostat in your loading room to "very low" when you are creating your "winter rounds". If you aren't shivering, then it is not cold enough. Store those rounds in the freezer. That way, when you go to shoot them, they will fire reliably and you will have consistent POI. 
That makes sense. Thanks. I would never have figured that out by myself.
I am old enough to know that a degree F refers to a temperature scale...
It actually tells you in the bottom left corner.
Cool chart, i think im going to print that off and put it on the wall.
Two examples of U.S sniping ammo and powder temp sensitivity, and all that was done was change powders.
1. Below was loaded with RL15 a double base powder rated 1.52 on chart.
Cartridge, Caliber 7.62mm, NATO, Ball, Special, M118LR (United States): 175-grain (11.3 g) 7.62×51mm NATO Match-grade round specifically designed for long-range sniping. It uses a 175-grain (11.3 g) Sierra Match King Hollow Point Boat Tail bullet. Produced at Lake City Army Ammunition Plant. The propellant's noticeable muzzle flash and temperature sensitivity led to the development of the MK 316 MOD 0 for Special Operations use..308 Reloading data only
2. Below the powder was changed to IMR-4064 and 0.45 on chart..308 Reloading data only
Cartridge, Caliber 7.62mm Special Ball, Long Range, MK 316 MOD 0 (United States): A 175-grain (11.3 g) round specifically designed for long-range sniping consisting of Sierra MatchKing Hollow Point Boat Tail projectiles, Federal Cartridge Company match cartridge cases and Gold Medal Match primers. The Propellant has been verified as IMR 4064 (per NSN 1305-01-567-6944 and Federal Cartridge Company Contract/Order Number N0016408DJN28 and has a charge weight per the specs of 41.745-grain (2.7 g).[19]
Old School .308 Winchester Match Loads
http://www.provenreloads-handloads.com/articles/2016/9/18/old-school-308-winchester-match-loads
.308 Reloading data only (read post #3 by Dan Newberry.... the Dan Newberry OCW or Optimal Charge Weight Load Development method or system for handloading)
http://www.sniperforums.com/forum/reloading/43364-308-reloading-data-only.html
1. Below was loaded with RL15 a double base powder rated 1.52 on chart.
Cartridge, Caliber 7.62mm, NATO, Ball, Special, M118LR (United States): 175-grain (11.3 g) 7.62×51mm NATO Match-grade round specifically designed for long-range sniping. It uses a 175-grain (11.3 g) Sierra Match King Hollow Point Boat Tail bullet. Produced at Lake City Army Ammunition Plant. The propellant's noticeable muzzle flash and temperature sensitivity led to the development of the MK 316 MOD 0 for Special Operations use..308 Reloading data only
2. Below the powder was changed to IMR-4064 and 0.45 on chart..308 Reloading data only
Cartridge, Caliber 7.62mm Special Ball, Long Range, MK 316 MOD 0 (United States): A 175-grain (11.3 g) round specifically designed for long-range sniping consisting of Sierra MatchKing Hollow Point Boat Tail projectiles, Federal Cartridge Company match cartridge cases and Gold Medal Match primers. The Propellant has been verified as IMR 4064 (per NSN 1305-01-567-6944 and Federal Cartridge Company Contract/Order Number N0016408DJN28 and has a charge weight per the specs of 41.745-grain (2.7 g).[19]
Old School .308 Winchester Match Loads
http://www.provenreloads-handloads.com/articles/2016/9/18/old-school-308-winchester-match-loads
.308 Reloading data only (read post #3 by Dan Newberry.... the Dan Newberry OCW or Optimal Charge Weight Load Development method or system for handloading)
http://www.sniperforums.com/forum/reloading/43364-308-reloading-data-only.html
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No BLC2 but shows other double base ball powders
H335 is the same powder as BLC2. The powders lots are split between the fast ones and the slow ones (844 vs 846). So BLC2 would have the sensitivity shown for H335.
Ooops. I see that there is no listing for H335 sensitivity, either. I guess Win 748 would be similar.
If you do try it, could you send me a PM with your results? I tried several loads on my 308 and never got anywhere near satisfactory results in terms of accuracy.
x2 on the IMR enduron line . Launched 10 rounds of 4166 at min load for fire forming/trigger time and results were surprisingly very promising, but this for a kissing cousin 7mm-08, south paw style bolt. This at -10c.
FWIW
Regards
Ronr
