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SaxonPig · May 4, 2013, 09:18 AM

I just can't stop beating my head against the wall, I guess.

Just for fun, here's a S&W ad from before WW II stating that the K frame M&P revolver can be fired with 38/44 ammo. The 38/44 load was a 158 lead SWC at 1125-1140 FPS and operated at far, far higher chamber pressures than current mainstream +P. Colt also advertised their D frame (Police Positive Special) as 38/44 capable (also pictured below). Comments from the doubters when I show these usually go "Well, they didn't know any better at the time" or "They didn't really mean it."

A retired cop I communicated with said he used 1,000 rounds of 38/44 he found in the department ammo locker through his issue M10 in the late 1950s with no effect. Not sure I would have done that, but he did, and if the 38/44 ammo didn't faze that K frame, current +P would be a lollipop by comparison.

Here's an ad for ammo marketed by S&W in the late 1960s and early 1970s (I think the time frame is thus). How about that 125 JHP at 1380 FPS? Doubters say "Well, they lied about the velocity." Granted, all ammo makers fudged a bit back before every Tom, Dick and Harry had a chronograph, but in my experience the inflation was on the order of 5% or so. Assuming a 10% inflated claim, that still leaves it at over 1200 FPS leaving the current +P at 925 in the dust. The lawyers told them to stop marketing truly hot ammo because of crappy imported guns floating around. So they started making weak and wimpy stuff and labeled it +P to fool the public into thinking one could buy high performance ammo.

As for the often repeated statement that there is no relationship between chamber pressure and velocity, hogwash. Pressure is what creates velocity. It's the pressure within the chamber that pushes the projectile out the barrel. The higher the pressure, the higher the velocity. Certainly manipulations can be made with powders and primers to a certain extent, but basically, if you want the bullet to go faster, you must raise the chamber pressure. The 38 goes 730 FPS at 16,500 PSi and the 357 pushes the same bullet to 1,300 FPS but running at 34,000 PSI. Obviously pressure and velocity are not in a straight line, and pressure goes up faster than does velocity. But there is most definitely a cause and effect relationship between velocity and chamber pressure. If velocities are reduced, like when the major ammo companies lowered the standard 158 38 Special from 840 to 730 FPS, so are pressures.

May 4, 2013, 09:18 AM	#40
SaxonPig Senior Member Join Date: April 24, 2006 Posts: 1,900	I just can't stop beating my head against the wall, I guess. Just for fun, here's a S&W ad from before WW II stating that the K frame M&P revolver can be fired with 38/44 ammo. The 38/44 load was a 158 lead SWC at 1125-1140 FPS and operated at far, far higher chamber pressures than current mainstream +P. Colt also advertised their D frame (Police Positive Special) as 38/44 capable (also pictured below). Comments from the doubters when I show these usually go "Well, they didn't know any better at the time" or "They didn't really mean it." A retired cop I communicated with said he used 1,000 rounds of 38/44 he found in the department ammo locker through his issue M10 in the late 1950s with no effect. Not sure I would have done that, but he did, and if the 38/44 ammo didn't faze that K frame, current +P would be a lollipop by comparison. Here's an ad for ammo marketed by S&W in the late 1960s and early 1970s (I think the time frame is thus). How about that 125 JHP at 1380 FPS? Doubters say "Well, they lied about the velocity." Granted, all ammo makers fudged a bit back before every Tom, Dick and Harry had a chronograph, but in my experience the inflation was on the order of 5% or so. Assuming a 10% inflated claim, that still leaves it at over 1200 FPS leaving the current +P at 925 in the dust. The lawyers told them to stop marketing truly hot ammo because of crappy imported guns floating around. So they started making weak and wimpy stuff and labeled it +P to fool the public into thinking one could buy high performance ammo. As for the often repeated statement that there is no relationship between chamber pressure and velocity, hogwash. Pressure is what creates velocity. It's the pressure within the chamber that pushes the projectile out the barrel. The higher the pressure, the higher the velocity. Certainly manipulations can be made with powders and primers to a certain extent, but basically, if you want the bullet to go faster, you must raise the chamber pressure. The 38 goes 730 FPS at 16,500 PSi and the 357 pushes the same bullet to 1,300 FPS but running at 34,000 PSI. Obviously pressure and velocity are not in a straight line, and pressure goes up faster than does velocity. But there is most definitely a cause and effect relationship between velocity and chamber pressure. If velocities are reduced, like when the major ammo companies lowered the standard 158 38 Special from 840 to 730 FPS, so are pressures.