35 Whelen
Member
I notice a few comments regarding the "temperature sensitivity" of W748. I am (and have been) using this powder for years with what I saw was success.
What happens to make this (and any other powder for that matter) "temperature sensitive" and how does that adversely effect performance?
Dan
A powder being temperature sensitive doesn't necessarily make your loads without success. Temperature sensitivity can cause two problems: If you work your loads up in warm weather, in cold weather velocity will likely drop. I learned this years ago when loading for my 257 AI using WW760. I worked the loads upm chronographing them, during mild fall weather. Then during the winter on a 20° morning, shot and chronographed the load again. While the load still shot accurately, the velocity had dropped 200 fps.
Conversely, if you work your load up in mild weather then shoot in hot weather, or your cartridges get hot, chamber pressure may increase.
Temperature sensitivity is something that occurs primarily with double-base powders and to my knowledge, all spherical powders (i.e.- WW748, WW760, H380. et al) are double base.
As I said in a previous post, check out Hodgdons Extrme Line of powders. You'll find their clain to fame is their insensitivity to temperature AND that their all single base powders.
748 - good for magnum shotshell, not so good for pistol
Dude, you got your numbers mixed up. 748 IS NOT a shotgun powder and only a pistol powder if you shoot centerfire rifle cartridges out of a handgun.
35W
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