A good and informative thread as I am currently working on my K-Frame .38 Special loads and Colt Official Police .38 Special loads.

As to the ad from Colt posted by bmcgilvray, I have seen several internet posted pictures of Colt Police Positive Specials in .38 Special which had cracked forcing cones, same as some M19s as reported here. Looking at the PPS one can see a forcing cone that is actually thinner its entire circumference over a M19 with its bottom shaved portion. I bought a Colt Police Positive [precursor to the PPS] in .38 S&W [note not "Special"] for that reason. I wanted the handgun type but I wanted it in a caliber that probably would not have a cracked forcing cone.

I think later that Colt did indeed warn not to use any +P in any of the PPS, Detective, and Diamondback revolvers [and their other small alloy .38 specials].

I have a tendency to agree with SaxonPig on most of what he speaks. In the past the loading manuals, ammo companies, and handgun makers all alluding to hotter loads being okay. Either lawyers or more modern testing equipment led to the latest loads appearing to be watered down. I tend to be careful with my loading anyhow and will load my K-Frame .38s with 158 grain lead bullets to about 900 fps, my K-Frame .357s with 158 grain lead bullets to about 1150/1200 fps , and my Colt Official Police[s] [they are the size of S&W L-Frames] with 158 grain lead bullets to about 1,000 fps . These loads are potent enough for "self-defense" and backwoods hiking and at the range I will shoot lead wadcutter loads.

As to the K-Frame .357 magnums. There is data on this forum that proves the forcing cones have been cracked by full magnum loads, mostly in the 110 to 125 grain persuasion, but I think one person reported it happening with 158 jacketed as well. And, there has been reporters here, such as SaxonPig, that prove otherwise with their guns.

Such is why I will load lead only 158 grain bullets in my K-Frame .357 magnums to the above mentioned velocities, AND I will stay away from H-110, W-296, 2400, and AA9, as the "magnum" powders [especially the ball types] have also been reported as having to contributed to excessive throat erosion and forcing cone cracking.

I too have noticed the +P loads seemed to be rather lukewarm as to velocities. There used to be +P+ loads as well wasn't there? But I don't think they are being manufactured any more by the larger companies.

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