My double action revolvers.

marano

New member
I just today thought about a peculiarity with my double action revolvers. I have three K FRAMES all in .38 and two J frame Smith & Wesson revolvers all chambered in .38 Special. I have three Ruger Six Series revolvers actually one of each(speed six, service six and security six and they are all.357. I also have a GP100 in .357. I guess I just figured I liked Smirths in.38 and the Rugers in .357.
 
just as well, as far as I am concerned. The K-frames will not stand up to a diet of nothing but magnum loads, so .357 mag versions must be used predominately with 38's. On the other hand, the Rugers will handle all the magnums you want to shoot.

I am a big fancier of Smith K-frames myself, but I skip the .357 mag versions and focus on the 38 specials. I don't have much use for magnum loads, anyway.
 
The K-frames will not stand up to a diet of nothing but magnum loads

Mmm, okay. I would phrase it as: full-house 357 Mag loads are better suited for beefier framed guns.

But I will certainly agree that K-frames are better suited for 38 Special. I only own one, and it's a 38 (Model 67). And I chose the Model 67 38 Special over the model 66 357 Mag for that reason. I saw no need to run mags when I already own three L-frames and a Python.
 
Phrase it any way you wish, Nick. I know that there is debate on this issue - always has been. Much of the variance in experiences regarding whether K-frames handle a lifetime of magnum loads has to do with the relative strength of the specific loads used. Not all 357 mag rounds are loaded the same, just as not all 38 specials are loaded the same, etc. The only way to have absolute, clear results on this is to do an extensive, long term ''apples to apples'' test. Anecdotal evidence from the field doesn't quite get it.

Smith & Wesson did just that sort of testing, when they designed and first produced the 357 mag versions of the K-frame. The test results, as far as I know, have never been made public. But, even S&W acknowledges that it is not a good idea to run nothing but magnum loads through K-frames. They have always recommended that 38's be used predominantly.

Anecdotal evidence, which I have seen firsthand, is that a K-frame fed a diet of nothing but hot magnums will develop frame stretch, (more than the slight amount that develops in every revolver anyway)... and as a result, usually will develop excessive endshake. It may take thousands of rounds, but it almost always eventually happens. At that point, the gun requires extensive repair. It's as simple as that. There are variances in the amount of frame stretch and thus the severity of the problem, from gun to gun......as well as variances in individual owner/ shooter's perception of the issue. Regardless, physics are physics.

And this is why Smith & Wesson no longer builds any* magnum revolvers on the K-frame. They have gone to the beefier L-frame, which is similar to the larger frame originally designed for the 357 magnum in the first place (when the 357 mags produced by S&W were referred to as "registered magnums" - though I think those were actually closer to N frames in overall size).

Debatable or not, I don't see much ambiguity in that.

*Update: Oops. Correction. Smith & Wesson has apparently put one K-frame 357 magnum back into production.....the model 66, as of 2014.
 
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the issue with K frames and magnums is not so much the frame but rather the forcing cone design in the K frames. (there is a reason for that, but that's another story). no such worry or disclaimers for their J frame magnums, in part to you won't shoot as many magnums in a J frame AND the forcing cone does not have the design weakness as the K frame's cone.
 
I have a couple K frame (Model 19 and 65) and one J frame (Model 640)S&W's, all in 357.

I typically carry all of them with 38 special loads (158 gr Hornady Defense rounds/Federal Premium) with a 357 reload close by. At the range, I try to mix it up by shooting some 357s through them, just to keep myself fresh, but modtly run 38s through them.

Just because I CAN shoot 357s through them, doesn't always mean I SHOULD (especially through that 640, geez that's a painful shoot).
 
K-Frames will stand up just fine to .357 Magnum ammo so long as you stay away from light bullets. The full-power 125 gr loadings in particular are the most problematic for the K-Frames because the combination of a relatively heavy charge of slow burning powder (the powder in a Remington 125 gr JSP looks suspiciously like H110/Winchester 296) and a shorter bullet (lighter bullets are shorter than heavier ones of the same caliber and construction) allows more extremely hot gas and burning powder to flow around the bullet and into the forcing cone and b/c gap. This in turn can eventually lead to excessive flame cutting of the topstrap and erosion/cracking of the forcing cone. Because the K-Frame's forcing cone in thinner at the 6:00 position, that is where the crack, if it develops at all, will usually occur. One of the changes made to the reintroduced M66 seems to be a slightly different geometry of the frame and forcing cone to alleviate the need for the thin area at the 6:00 position.

The shorter, lighter bullets don't completely seal the chamber throats before the base of the bullet leaves the case thus allowing a certain degree of blow-by. Also, the lighter bullets require less pressure to be pushed out of the case so a larger percentage of the powder burns in the chamber throat and barrel as compared to a heavier bullet which requires more pressure, and thus a larger percentage of the powder charge, to push the bullet out of the case. Finally, in full power loadings, lighter bullets typically have a heavier powder charge than heavier bullets due to the increase in case capacity.

So long as you restrict your use of Magnum ammunition to that with 140 gr or heavier bullets, you are extremely unlikely to have issues with a K-Frame beyond normal wear and tear.
 
I bought this around 1990 from a retired federal officer. He carried it for 19 years and never shot anything except full power 125 JHPs in it. I have never shot anything except full power 125 JHPs in it. So far, no problems.

Suggestion on Magnum K frames: keep the forcing cone clean to avoid carbon hot spots as this may be the cause of fracturing.

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