125 grain .357 bullet damage..??

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codefour

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I do not know if this is in the correct thread to put this in. I have a question that maybe one of THR members can shed some light on.

I was recently told by a friend that his gunsmith told him not to shoot 125 grain .357 Magnum cartridges in a .357 Magnum revolver. The reason for this I was told was the 125 grain bullets in a magnum cartridge/gun would damage the forcing cone. The gunsmith told my friend to use 158 grain bullets and higher when shooting .357 Magnum cartridges. The gunsmith said it was fine to shoot 125 grain .38 Spcl rounds becuase they do not cause forcing cone damage.

Has anyone ever heard of this..?? I reload my own and was about to place an order for .357 Mag bullets. I like 125 grain .357 Mag for the higher velocity and energy but I do not want to damage my .357 revolvers.

Thank you in advance for any responses.
 
There are many threads. However to help you find them, most of the issues are with lighter K frame S&W revolvers - 13, 19, 65 & 66 - so look for those. Basically they were designed to use .38 special to train and .357 to fight. If you shot lots of .357 you can cause problems with those revolvers. In the end S&W threw in the towel, stopped making them and came out with the slightly larger L frame revolvers instead.

Search on those models or on K Frames & .357 and you should find copious amounts of detail.
 
I don't remember where I got this, but it's an interesting read.

The 125 grain bullets driven to maximum velocities used large charges of relatively slow-burning powders. Handloaders know the powder types as WW296 and H-110, among others. The combination of slow ball-type powders and the short bearing surface of the 125 bullets allows prolonged gas cutting of the forcing cone and top strap area, accelerating erosion and wear.

Borescope studies of rifle, machine gun, and auto cannon chamber throats shows a lizzard-skin-like texture due to this gas cutting damage, called "brinelling". The results of brinelling are fine microcracks that weaken the surface of the steel, and further promote erosion. In machine guns and auto cannons, barrel life is measured in terms of "useable accuracy", and round counts that determine this are based on group sizes at engagement ranges.

In the K-frame magnums, the forcing cone dimensions combined with the barrel shank dimensions results in a relatively thin shank at the 6 o'clock position, where a machine cut is made to clear the crane. This is usually where the forcing cone cracks. The L and N frames use much beefier barrel shanks and do not have this cut. S&W intended the K frame magnums to be "carried much and fired seldom" service arms, designed to fire .38 Specials indefinitely, with light to moderate use of .357 Magnums. You notice that S&W has discontinued production of K frame .357 magnums, no doubt due to product liability issues and a couple generations of K frame magnum experience.
 
I have re-loaded thousands of 125grn 357 mag bullets and have only had a problem when I use to use Blue dot (Alliant has since recomended not using BD with 125grn bullets) I use faster powders for plinking now (Universal, Unique ) to no ill effects.
 
Try this search on Google, exactly the way I type it in:

"forcing cone" site:thehighroad.org

You will get lots of hits about issues involving forcing cones including damage due to .357 mag usage.

Then change out thehighroad.org for any other site you want to search.

Take care

JJ

P.S I then tried "357" "forcing cone" site:thehighroad.org and got better results.
 
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Short answer: Yes, lighter weight .357 bullets such as 125 grain and lower can damage the forcing cone over time and even cause flame cutting on the top strap of the revolver (this latter effect is usually self limiting in steel firearms).

If your firearm is a Ruger, don't worry about it ;)

If your firearm is a K-frame or similar sized S&W, you may want to keep an eye on the forcing cone after shooting them.

One hypothesis is that high pressured gasses escaping from the cylinder gap/bc gap hit the metal hard due to the smaller size of the lower grain bullets. This hypothesis submits that heavier/larger bullets do not allow the gas to escape with as much pressure and force.

Another hypothesis submits that any 'hot' load will eventually cause erosion of the forcing cone and top strap.

I had my Gp100 personally looked at by Ruger's gunsmithing team and was told that the flame cutting to the top strap was negligible and did not constitute damage to the firearm. A forcing cone is another issue, however, so if you see cracks along its diameter, you may wish to have that area smoothed out with a tool by a professional.

All in all, I wouldn't worry about it much if you have a robust gun. These things are for shootin', after all. A much more likely scenario is very hot loads knocking the timing of the firearm loose before noticeable damage to the forcing cone.

Good luck!
 
Hi,
If your firearm is a Ruger, don't worry about it
Yes I would. There is one member on this forum that wore his GP100 out by shooting lots of 125 gr "frame throwers".

The answer to your question on 125 gr "flame throwers" is yes. Using high amounts of 125 gr magnums will erode the forcing cone and increase flame cutting. Flame cutting is self limiting but think of this. Using 125 gr magnums in any revolver is like a blow torch effect on the revolver. Its hard on the revolver. Now I talking about 125 gr rounds that have a velocity of over 1500 fps. There are some medium power rounds like the 125 gr Remington Golden Sabers that will not cause this problem. There velocity is only in the 1250 fps.
Best advice is, use 140 or heavier gr rounds. I do. Actually your gunsmith gave you good advice.
Regards,
Howard
 
If the Remington Golden Saber 125g JHP is loaded lower than most factory 125g ammo, can I use it in my Model 66 without the risk of damage? Right now I also only shoot 140g or above also.
 
If the Remington Golden Saber 125g JHP is loaded lower than most factory 125g ammo, can I use it in my Model 66 without the risk of damage?
You will be okay with the Golden Saber round. But this is a expense round to use for practice. One of my favorite rounds for practice is the CCI blazer 158 gr hollow point 357 magnum round. I use this round in all my 357 magnum revolvers including my four K frame magnums. This round is a excellent practice round and won't be a issue with any 357 magnum revolver. I don't reload so this round is my favorite. I buy this round for $20.00 for a box of fifty.
Regards,
Howard
 
I believe this problem was discovered with the Model 19. I use 173 gr. Keith LSWC for both the .38 Spl. and .357 Mag.
 
The corbon DPX .357 load and the corbon "Thunder ranch" DPX .357 load have comparative velocity and recoil to the golden saber, with the benefit of newer bullet technology. However, you pay for what you get.

Re: The gp100, I'd like to see photos of that ;) Even if it did "wear out" I'm sure Ruger would take care of it, whether that meant setting the gun back in time or reaming the forcing cone. They stand behind their products. Although even the most sturdy firearms can be worn out by user abuse...

Re: S&W model 66, as mentioned in my first post, I would stay away from very hot loads in the k frame revolvers during routine practice. If I were you I would load the DPX. Although the gun can probably take the hot loads for CCW purposes.
 
Thanks for all the responses and links. I only have one K-frame model 66. The other is a 686. I was about to place a bullet order to resupply my reloading components. If I order 125 grain, I get 3750 bullets. If I order 158 grain, I get 3,000 bullets. All are coming from Montana Gold Bullet.

I guess I will play it safe and order the 158 grain JHP for target shooting. I can load those pretty warm, better than factory velocity, with much more accuracy.

Once again, thank you to THR members.
 
I am the owner of the GP 100 with the trashed forcing cone. The 125 gr. loads I was shooting in it would have done exactly the same thing to any brand of revolver. The load (16 gr Blue Dot) was listed in the Speer No 11 manual but was removed in the next edition. It was a safe load as far as pressure. But it produced a very hot flame and hit the steel with a lot of force over a longer period of time than most factory loads. Don't take my word for it, in Kuhnhausen's Ruger Shop Manual he shows a number of photographs of burned up Ruger forcing cones. When you see cracks in the forcing cone it is not something that can be repaired by "a smith with a tool." I can't imagine why you would believe that Ruger would cover barrel replacement "under warranty" under the conditions. All of the 110/125 gr. .357 loads I have shot have convinced me that using a bullet that lightweight accomplishes nothing but high velocities and gas cutting. If a guy likes to shoot a revolver while producing a huge amount of muzzle flash then their gun is not going to last as long as one used for heavier bullets and more traditional speeds. It's not a theory, it's the laws of physics.
 
You seem to blame the 125 grain bullet weight for an issue caused by the powder and load you were using. These are two different issues, and I daresay most rugged revolvers would be fine with a steady diet of 125 grain bullets provided they aren't especially hot "flamethrowers" as you call them. Case in point: The golden saber and DPX loads I mentioned earlier share 125 grain weight but are mildly loaded for the caliber.

.38 special rounds are typically 125 grain, 115 grain, even 110 grain. Yet, these bullet weights in that caliber are not known for destroying forcing cones. One could make a point that the magnum rounds with light bullet weights create the -potential- for forcing cone damage dependent on powder and how fast the load is pushed. In such cases, heavier bullet weights may decrease the speed of erosion by reducing the amount of time the cone and top strap is exposed to the damaging medium. However, bullet weight itself does not cause the damage, but is rather one factor among many that may influence the rate of erosion of the forcing cone.
 
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Does Taurus make a .357 that is equivalent to the S&W K frame?

If so does it suffer from using too many 125 grain loads also?
 
I used to use Blue Dot in 125 grainers until Alliant issued their warning not to use it for one reason or another. However, my load was only 14 grains, which I found plenty stout. One of my King Cobras has injested a few thousand of that load over the past 20 years and has no signs of damage. Due to the warning, I swapped to Power Pistol. I currently have 3k loaded and will keep on feeding them to my guns without much concern.
 
I am the owner of the GP 100 with the trashed forcing cone. The 125 gr. loads I was shooting in it would have done exactly the same thing to any brand of revolver. The load (16 gr Blue Dot) was listed in the Speer No 11 manual but was removed in the next edition. It was a safe load as far as pressure. But it produced a very hot flame and hit the steel with a lot of force over a longer period of time than most factory loads. Don't take my word for it, in Kuhnhausen's Ruger Shop Manual he shows a number of photographs of burned up Ruger forcing cones. When you see cracks in the forcing cone it is not something that can be repaired by "a smith with a tool." I can't imagine why you would believe that Ruger would cover barrel replacement "under warranty" under the conditions. All of the 110/125 gr. .357 loads I have shot have convinced me that using a bullet that lightweight accomplishes nothing but high velocities and gas cutting. If a guy likes to shoot a revolver while producing a huge amount of muzzle flash then their gun is not going to last as long as one used for heavier bullets and more traditional speeds. It's not a theory, it's the laws of physics.

Man, you can learn something new everyday at this site. I have a fairly new GP100 (4" blue) that I have been shooting "hot" 125 JHP loads in (maybe 300 rounds up to this point). This is a published load of 20 grains of W296 under a 125 grain JHP.

Ain't gonna do this anymore. I have 100's of 125 grain JHP's on hand but I'll load them into .38 Special +Ps for practice with my three .38 revolvers.

I just ordered 500 158 grain Hornady XTP's for the .357 from now on.

Thanks for the heads-up!

Dan
 
If your firearm is a Ruger, don't worry about it

The -Six guns had the same smaller dimensions and machine cut at 6 O'Clock as the K-frame Smiths, and suffer from the same split forcing cone issue when used extensively with light/fast loads. My Security-Six locked up tighter than a drum on account of it.
 
Now I (sic) talking about 125 gr rounds that have a velocity of over 1500 fps.
^^This....if you are shooting "old school" max-power 125 grain .357 loads, you may have to keep an eye on your revolver.

The ammo that you buy today does not meet that criteria. If you handload (as I do) load .357s with 158 gr bullets in mid-range power factors, and the revolver will outlive you.

I shoot my old M66 with moderate 158s and carry it with hot 125s. Oh, I have put some hot 125s through it to see what it feels like, and it's not all that much different...but I cannot afford enough hot 125 ammo to see if I can wear it out. :)
 
My 125 gr JHP's over 10.0 grs. of Power Pistol average 1422 fps out of my 6" King Cobra. I shoot piles of them. I have no reservations about feeding them to a Python, either.
 

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The OP question is how much damage can occur to a revolver shooting the 125 gr 357 magnum round. The answer is yes. Depending on the type of round, the higher velocity rounds such as Federal, Remington, Black Hills will erode a forcing cone and increase flaming cutting on all revolvers. This discussion should not be which revolver will hold up the longest. All revolvers will be affected by shooting the 125 gr 357 full power rounds. Again, these are the higher velocity rounds.

Whether a person wants to shoot these rounds is his or hers decision. Personally, I don't anymore. I have eight 357 magnum revolvers. From K frame to a Blackhawk. Throw in a S&W 686, GP100 and a Security Six. I don't shoot and 125 gr flame throwers in any of them. I stick with 140 gr or higher. My personal favorite for defense is the Winchester Silvertip. I practice with CCI blazer. The Winchester is 145 gr and the Blazer is 158 gr. A person can shoot hundreds of rounds with either and not have a problem as a result.

I think this thread has been answered.
Regards,
Howard
 
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