Ammo Question for GP100

[jonnybigguns]

I was wondering if a GP-100 can swallow 125 grain 357 mag. rounds? I've been told the Smith and Wesson 66 can't handle the 128 grain loads, extensive 125's could cause cone cracking, I know Smith beefed up the revolvers introducing the 686, I'm assuming the GP 100 is designed to handle these loads? How about a security 6 357?

 

[omalon]

YES, it can....

 

[MMichaelAK]

*laughing*

The Smith can't.
The GP100 can, all day long.

 

[Anonymous]

Today I loaded Hornady xtp 125 grain 357 loads for my gp100. I can't wait to get to the range to squeeze them off.

 

[mattsbox99]

I've loaded lots of 125s and 110s for mine, with no issues. They sure have a lot of muzzle blast!

 

[maxpress]

the lighter hotter loads cause flame cutting more readily on the smiths according to a guns and ammo article some years ago. they had a smith 686 go up against a gp100 with 5000 rounds. neither did great but the ruger came out ahead and smoothed out broke in.

i cant see shooting 5000 hot 125s out of any of my 357s in there life but its nice to know you can. i shoot alot of 158swc in 357 cases loaded to about 38+p and about 10% 158 full house loads. course when i have one on the nightstand or town carry it has 125 hps in it.

 

[jimbo1096]

Oh yes it certainly can! I've even reloaded down to 95gr remington jhp as hot as possible and had no problems.
Shot 'em out of the SP tto, just for the hell of it.

 

[Rex Driver]

This makes me kinda glad that I mostly stick to 38 Spl rounds loaded to a little less than +P or with lead 125 Grain bullets loaded a little hotter than "Cowboy Loads" in my 357s.

 

[WyoGunner]

no problemo

 

[bub]

jonnybigguns, the problem with the S&W M66 is that it allegedly wasn't really designed for .357. It was designed for .38. All the M66 is, is a Model 10 that was stretched slightly to fit .357 in. Supposedly, heat treat was also different, too. In order to get the gun as small as it was for the caliber, the bottom of the forcing cone had to be milled off to make room for the crane (or yoke or whatever S&W calls it) to close. This results in a weak spot on the forcing cone where it was milled away.

Allegedly, as long as you don't use light bullet weight .357 loads (like the 125 and 110 gr loads), the M66 was good to go...for a while. Allegedly, even with the heavier bullet loads, M66s shot loose after a moderately steady diet of full-house .357 ammo. Also allegedly, the M66 was designed in a time when you practiced with .38 and carried .357, or so the story goes. This was why it was designed the way it was.

With the GP100 and M686, the guns were designed from the ground up to shoot the lighter, faster, more violent .357 loads. While there is healthy debate on which is actually stronger, it would take a LOT of shooting full-house .357 loads through either of them for them to wear to any appreciable extent. They are just larger, stronger guns. Shoot anything you want through your GP100. I'd bet they you will wear out before the GP wears out!

Bub

 

[jonnybigguns]

Thanks' guy's for all the info.

 

[JimMarch1]

The GP100 can handle anything within the realm of 357 ammo, in dang near unlimited diets.

The Security/Service/Speed series is almost as tough. While it's not as beefy as the GP100, it's still stronger than an S&W K-frame by a good margin. Ks have a weak spot - the 6O'clock position at the barrel's rear end has a flat spot necessary for crane clearance. That's where the crack always starts when you shoot fair amounts of hot 125s. None of the Rugers have anything like that, DA or SA. Even the SP101 is tougher than a K-frame 357.

As an aside: the Ruger "mid-frame" single actions in 357 (New Vaquero, Montado, 50th Anniversary 357 Flattop) are even tougher in all respects than a GP100. And the large-frame SA regular post-1973 Blackhawk 357s are tougher yet, built on a true 44Magnum-class frame.

 

[roaddog28]

jonnybigguns, the problem with the S&W M66 is that it allegedly wasn't really designed for .357. It was designed for .38. All the M66 is, is a Model 10 that was stretched slightly to fit .357 in. Supposedly, heat treat was also different, too. In order to get the gun as small as it was for the caliber, the bottom of the forcing cone had to be milled off to make room for the crane (or yoke or whatever S&W calls it) to close. This results in a weak spot on the forcing cone where it was milled away.

Allegedly, as long as you don't use light bullet weight .357 loads (like the 125 and 110 gr loads), the M66 was good to go...for a while. Allegedly, even with the heavier bullet loads, M66s shot loose after a moderately steady diet of full-house .357 ammo. Also allegedly, the M66 was designed in a time when you practiced with .38 and carried .357, or so the story goes. This was why it was designed the way it was
With the GP100 and M686, the guns were designed from the ground up to shoot the lighter, faster, more violent .357 loads. While there is healthy debate on which is actually stronger, it would take a LOT of shooting full-house .357 loads through either of them for them to wear to any appreciable extent. They are just larger, stronger guns. Shoot anything you want through your GP100. I'd bet they you will wear out before the GP wears out!
Bub

Shoot em up in your GP100. The GP100 and the Smith 686 will handle the lighter grain 357s. Bub is write. I have a GP100, Smith 686 Ruger Service Six and a Smith model 28. All the above revolvers I mentioned will handle the lighter grain full power 357s. The 19/66 was a 38 special that was modified to shoot 357s only when needed to. I have two model 66s and I only shoot 357s occasionally. And only 140gr or higher. The GP100 was made to shoot any factory 357 availiable.
You should not have a problem.

roaddog28

 

[Montelores]

Why would shooting 125 grain bullets be a question? Do they produce more pressure, or is there more/faster burning powder? Are they more powerful than 158 grain cartridges?

Also, shouldn't any revolver manufactured as a .357 be able to handle any factory .357 loads?

Thank you,

Monty

 

[JimMarch1]

>>Why would shooting 125 grain bullets be a question? Do they produce more pressure, or is there more/faster burning powder? Are they more powerful than 158 grain cartridges?<<

Two issues: with a lighter bullet loaded hot, you use more powder and faster-burning powder, which tends to act like a cutting torch flame against the back of the barrel and the topstrap.

Second, the 125s accelerate faster so they hit the forcing cone at the back of the barrel moving faster than a 158 or heavier slug would.

A K-Frame S&W 357 can't take too much of these effects, esp. in combination. For starters there's a weak spot at the back of the barrel at the lowest position where it gets clearanced a bit for the crane.

The Ruger Security/Service/Six series wasn't much beefier than a K-frame so the assumption was these issues would eventually eat one too.

>>Also, shouldn't any revolver manufactured as a .357 be able to handle any factory .357 loads?<<

The K-frame was made for shooting mostly 38s in for practice, and a small diet of 357. That was the thinking behind building it. It ended up leading the way for a whole lot of much weaker "357s" by Taurus and others and eventually led to a reduction in the 357 SAAMI pressure levels. Ruger more than anybody fought that trend and made "real" 357s that could handle original-spec ammo.

 

[Montelores]

Thank you very much, Jim.

So typically, lighter bullets are loaded with more, faster burning powder to give them greater velocity, and therefore more energy? It seems that self-defense rounds are usually of a lower weight, so that would make sense. I am trying to understand the physics of the issue.

Also, what are considered "lighter" loads for a .357 (brands or bullet weights), if I want something with less recoil? I am new to the .357 world.

Monty

 

[JimMarch1]

If you have two loads, one at 125gr and one at 158, and you're trying to get the same energy, the 125 will be nastier on the gun. More powder, faster burning type, more flame, more noise for that matter.

 

[Montelores]

Thanks, Jim. I was editing my post with an additional question when you responded.

Monty

 

[JimMarch1]

Ah. 125 is where "light" starts. 140 is considered middleweight, "heavies" start at 158.

Cor-bon has had a hot 140 for a while, Winchester has had a 145 loaded a little on the mild side, Speer has the very mild 135. I think Buffalo Bore has a middleweight. Other than that, most of the action is in 125s, 158s and heavier for hunting (almost always hardcast lead). Penn Bullets has that insane 230gr slug that has to be seen to be believed.

 

[jpickar]

I would shoot anything that is safe to shoot in the GP100.

S&W K frames are very spotty with this problem. Some forcing cones crack and others have shot thousands of rounds with the 125 gr bullet and no problem.

I have a 66 that is a ex Wyoming highway patrol gun and has shot thousands of rounds of 125 gr. bullets and is in very good condition.

That said I do not shoot 357's out of my 66's only my 686 and Rugers.

John