Excerpt from:
38 Special (+P) and 38-44: Pet Loads for Heavy Framed Revolvers - Handloader #304 (Oct-2016), Brian Pearce
...while (+P) rated ammunition was listed with an average working pressure of 20,000 psi, a significant pressure decrease when compared to vintage .38-44 loads. The velocity of 158-grain bullets in (+P) ammunition decreased by more than 200 fps when compared to the .38-44 loads.
Currently there are no industry pressure standards for the .38-44. Having fired tens of thousands of .38-44 loads in Colt Single Actions and Smith & Wesson N-frame revolvers at targets, pests, varmints and big game, I appreciate their accuracy and performance.
Many loads can approach or duplicate .357 Magnum ballistics, which makes them suitable for long-range rockchucks, coyotes or deer-sized game under ideal conditions.
For these reasons I have listed .38-44 data for heavy-framed revolvers that are in good condition, with the test gun being an early post-World War II Smith & Wesson 38/44 Outdoorsman.
Many of the maximum loads approximate .357 Magnum pressures (35,000 psi) and should never be used in light-framed .38 Special revolvers.
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