I have a model 66 k frame as u probably know and i am told not to shoot to "hot" of a load through it but i don't get what the grain of the bullet has to do with it. i figured the lower the grain the less hot it would be but i guess i am mistaken. I have 125 grain remington golden sabers and i am told that that is a no no. Please help me find a round that i can use both at the range and for self defense that wont harm my gun. And yes i do mostly shoot 38 out of it but i want to be able to reliably shoot 357 out of it when the time comes for it. Any help is appreciated.
I dont understand
- Thread starter VivaElZo
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The 125 grain bullets leave the cylinder much faster than heavier bullets, allowing a higher volume of super-hot burning powder and gasses to exit the cylinder, much more so than do slower accelerating heavier bullets. Those gasses do two things which are deleterious to K frames - deep flame cutting of the top strap and, even more serious, erosion of the forcing cone, leading to a cracked forcing cone and a barrel in need of replacement, and S&W no longer makes barrels for those guns. In contrast, 158 grain loads (for which the guns were designed) do not cause such damage, although minor flame cutting may be experienced, but almost no potential for forcing cone cracks, unless a lot of 125 grain loads were run through the gun previously. Remember, the original 357 loads were 158 grains, the 125 grain loads didn't come on the scene until the early 1970s, long after the K frames were designed, and the 66 is a 19 in stainless, not a new design.
scooter123
Member
It's a personel theory but remembering my high school Physics tells me that Kinetic Energy is a function of Mass time the Square of Velocity. So, a lighter and faster moving bullet can strike the forcing cone with a bit more energy than a slower and heavier bullet. If you also factor in that lighter bullet should also accelerate a bit faster initially than a heavier bullet, it may be possible that difference in the energy level of the bullet striking the forcing cone may be as much as say 50%. It might explain those reports of forcing cones cracking with as few as 50 rounds fired, a total which to me indicates that gas cutting would not be a factor.
Whatever that actual Physics involved, it's been well established that it's the light weight bullets that do the MOST harm and the common advice is to limit Magnum use in the K frames to 158 grain bullets.
It's also a common recomendation to limit the use of the Magnums in the K frame to protect the barrel even if you are using 158 grain bullets. Personally, I find the K frame a bit too light for comfort and the 357 Magnum so I limit my shooting to 38 spl. in these revolvers.
I'll also point out that IMO the 357 Magnum is a poor choice for a Defense caliber. There are just to many good 38 spl. loads available to today that provide good expansion without the noise or concern for over penetration that comes with choosing the 357 Magnum.
Whatever that actual Physics involved, it's been well established that it's the light weight bullets that do the MOST harm and the common advice is to limit Magnum use in the K frames to 158 grain bullets.
It's also a common recomendation to limit the use of the Magnums in the K frame to protect the barrel even if you are using 158 grain bullets. Personally, I find the K frame a bit too light for comfort and the 357 Magnum so I limit my shooting to 38 spl. in these revolvers.
I'll also point out that IMO the 357 Magnum is a poor choice for a Defense caliber. There are just to many good 38 spl. loads available to today that provide good expansion without the noise or concern for over penetration that comes with choosing the 357 Magnum.
Steve C
Member
Typical full power 125gr JHP ammo from the major manufacturers runs at 1,450 fps from a 4" revolver. Remington loads their Golden Saber .357 mag at a more moderate velocity of 1,220 fps while their Express and UMC ammo is full power at 1,450 fps.
The issue with the .357 mag K frame is the cracking of the forcing cone at the thinned out area as the picture below illustrates with a comparison between a model 66 and a model 27 N frame. Some K frames have stood up to shooting the 125gr full power loads quite well and have not cracked after a thousand rounds or more while others have cracked after only a few hundred rounds. I have ran a couple hundred rounds of full power 125gr loads through my 66-2 and it has not cracked yet.
Though I still keep it loaded with Speer 125gr Gold Dots for defense I limit its use of 125gr bullets to self defense and shoot only heavier 158gr jacketed or lead .357 mag bullets or .38 spl for practice after reading articles about the cracking issues. I wouldn't worry about shooting the lower powered Golden Sabers at all. They're better than any .38 spl loading for self defense. The 125gr full power loading has the reputation as being the best man stopper and if needed for self defense of ones life any subsequent damage to the gun isn't of much importance.
The issue with the .357 mag K frame is the cracking of the forcing cone at the thinned out area as the picture below illustrates with a comparison between a model 66 and a model 27 N frame. Some K frames have stood up to shooting the 125gr full power loads quite well and have not cracked after a thousand rounds or more while others have cracked after only a few hundred rounds. I have ran a couple hundred rounds of full power 125gr loads through my 66-2 and it has not cracked yet.
Though I still keep it loaded with Speer 125gr Gold Dots for defense I limit its use of 125gr bullets to self defense and shoot only heavier 158gr jacketed or lead .357 mag bullets or .38 spl for practice after reading articles about the cracking issues. I wouldn't worry about shooting the lower powered Golden Sabers at all. They're better than any .38 spl loading for self defense. The 125gr full power loading has the reputation as being the best man stopper and if needed for self defense of ones life any subsequent damage to the gun isn't of much importance.
Use the 38 's for practice, shoot some "full house" 125 gr so you know where they hit, and can deal with the recoil. Then carry the 125 gr 357 mag of your choice and call it good. IF the forcing cone does crack ( my 19 6" has over 2k 357's through it ) let smith & wesson repair it or sell the gun and by and L frame and shoot 357's for as long as your hands and wallet can handle it. The 125 gr 357 is considered the number 1 manstopper, if I am carrying for self defense I want my best option- I do not care about the forcing cone. I can always replce a gun but not my life or my family. Be Safe.
If you check the specs on the 125 gr golden saber, you should find that it's a "medium velocity" round, and not one of the high velocity 125 gr rounds linked to damaged forcing cones. Don't know if it would be better or worse than the 158s.
kshock
Member
Unless you are planning on shooting alot of those 125's, I don't think you need to worry. I carried a 66 for years as a duty gun, always with hot 125's. Don't remember even one of the departments guns being damaged by them (some damage to shooters hands maybe....those things we shot kicked and kicked hard). I am sure there have been guns damaged by this, but I don't think it is something to worry about if you only shoot them occasionally or rarely.
I had the forcing cone split on a Model 19 I owned. When it happened, it pushed back against the cylinder, binding it solid, and making it impossible to fire the gun. I would not like that to happen during a life-or-death situation. No more hot 125 grain 357 loads for me in a Model 19, although they do have a reputation for getting the job done.
Dragon88
Member
Here's a picture of two of my handloads:
The one on the left is pushing about 790 fps and is safe to shoot in any 38 Special or 357 revolver. The one on the right is pushing 1575 fps and will eat K frames alive if used extensively through them.
Both are 125gr bullets.
You have to consider a lot more than just the weight of the bullet.
(Remnants of an art project in the background. Ignore the dust.
)
The one on the left is pushing about 790 fps and is safe to shoot in any 38 Special or 357 revolver. The one on the right is pushing 1575 fps and will eat K frames alive if used extensively through them.
Both are 125gr bullets.
You have to consider a lot more than just the weight of the bullet.
(Remnants of an art project in the background. Ignore the dust.
)
