Quote:
Caliber of tested cartridge was .243 Winchester, bullet weight 80 grains, powder then-new NORMA MRP, and the charge... surprisingly... just 15 % less than a maximum (compressed !) load. It was STILL A REDUCED CHARGE DETONATION; not one caused by an excessive charge, because the charge could not be excessive with those components in use. Light bullet and slowly burning powder is not an advisable combination of loading components for .243 Win., known as a caliber prone to S.E. Effect. (It's "big brother" .308 and "kid brother" .22-250 are considerably less risky; last mentioned presumably because of more steep 25 degrees shoulder angle).
Needless to say: All the loading components were examined carefully afterwards. They were faultless. Just the burning rate of powder was selected wrongly for the bullet weight. MRP powder is O.K. for .243 Win., but for the heaviest bullets of this caliber; weight 100 or 105 grains. For the most usual 90 grainer bullets is some more fast-burning propellant advisable.
Noted was a slightly less than a tenth of second lasting delay between hit of a striker and explosion. This same delay is noted also by survivors of S.E.E. accidents, if they can remember something from the "big bang". (Usual recollection is: "I squeezed the trigger and woke up in the hospital"). If the delay lasts a second or more, it is just an usual hang-fire, without signs of excessive pressure.
<snip>
P.S. That story about two broken .243 Win. test-barrels and purposeful courting of S.E.E. in Germany is told in the book "Handbuch für den Wiederlader" by K.D.MEYER, who was then a director of German DEVA Institute.
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I've never heard of SEE in a handgun. That doesn't mean it can't happen, but it's highly unlikely.
One of the moderators on another forum shot some factory .357 Mag loads that clocked less than 1100 fps and I believe the bullet was less than 158 gr. That's hardly what I call a .357 Mag load, but that's what the manufacturer sells for that application and it's for self defense! Manufacturers have some strange ideas on a lot of subjects.
I have about 8 pounds of Blue Dot on hand. I rarely load it in handgun cartridges, but if I want to, I will. One reason is, it rarely gets down to 20 degrees around here. Another reason is, Alliant has no idea what gun I'm shooting, or its condition. I mostly use 2 N frames, a Dan Wesson and 2 rifles, all in .357 Mag. The rifles will clock 2200 fps with 125 gr bullets, but I don't use Blue Dot to do that. The 6" N frame will clock 1600+ fps with a 125 gr bullet, but not with Blue Dot.
The book recommended 14.5 gr of Blue Dot with a 125 gr bullet is, in my experience (1/23/04), a 1.5 gr overload and it has been that way too long. In fact, it was as late as 2004 & 2005 that Alliant published that load in their reloading guide. Then in 2008, they list only 16.0 gr of Blue Dot with a 110 gr bullet and 11.5 gr with a 140 gr bullet. It took them 33 years, give or take a little, to correct an overload problem that should have been apparent long ago. The only problem is, they didn't correct anything, but instead, they ignored it, so maybe it'll go away. A warning isn't a solution, reducing the loads is the solution.