Quote:
Originally Posted by Ralph G. Briscoe
I've been working up a max standard pressure defense load for use in my vintage Detective Specials. 158 gr LSWCHP/Unique/Winchester primers. The data are is over the map--
Hornady 1973 manual--max 6.1 grains (not designated +P)
Speer 1974 manual-- max 4.7 gr
Lyman 1970 manual-- max 5.4 gr
Lyman 1973 cast manual--max 5.1
Hornady 5th edition manual--max 4.2
Alliant manual-- max 4.3 gr (they list 4.5 gr as "plus P")
Any wise advice as to how hot I can safely load for these old guns would be appreciated. I recently saw a vintage Colt ad which listed the ammo suited to the D Special. They included the 38/44 loads--no thanks  |
Alliant website suggests 4.7 grains of Unique as maximum.
I see you have been cooking some 4.7 loads. I don't think
5.0 would give you a problem, but don't push it if you don't
need to.
The great variability of load data from antiquity is due to our
grandfathers testing loads in standard revolvers, and then
looking for signs of pressure. SAAMI .38 Special max is 17k.
If you shot loads at 30,000 psi, you may get no pressure
signs at all. Primers have no problem with 30k psi. Your first
sign of pressure in your old revolver could be when it shoots
loose. Ruined.
Modern load data comes from testing with instrumented
guns, or even instrumented test barrels. Modern data should
be used whenever available.
Joe