SP101 Question

J

janieoakley

New member
We have an SP101 3" Barrel 38 Special, It seems to be exactly like the SP101 357....Can we shoot 357's out of our 38? It is a Stainless Gun, And as far as I can tell they are the same. Any body know for sure????
 
If the gun is designed for .38 Special you cannot shoot .357 Magnum through it. It should'nt fit in the cylinder but if by some chance it does its still a much higher pressure than a .38 Special is designed for.
 
It's not "exactly" like the .357 SP, as you'd find if you try to load it with the longer .357 rounds.
The .38 chambers are too short to allow the magnum rounds to fit far enough to close the cylinder, as Ja says.
Denis
 
even if the 357 mags COULD chamber in the gun, it would be EXTREMELY unsafe to fire, and would almost surely result in destruction of the gun and serious injury to you and/or those around you
 
You can't assume they are the same gun, regardless of whether or not magnums fit in the chamber, so no, it's not OK.

Check you owners manual about ammo. It should say that .38 spl +P is OK to fire. That makes it pretty potent as is.
 
It's not "exactly" like the .357 SP, as you'd find if you try to load it with the longer .357 rounds.
The .38 chambers are too short to allow the magnum rounds to fit far enough to close the cylinder, as Ja says.
Denis
Click to expand...

What he said. You can shoot .38s out of a .357 but not the other way around.
 
I seem to remember that a lot of folks were shooting short .357 loads from the early guns and a number of gunsmiths were converting the cylinders to chamber 125 gr. .357 loads by reaming them out longer. Never head of one blowing up. The only real limitation of the early models was that with a heavier (longer) bullet it would stick out the front of the cylinder. Ruger's first .357 model of the SP was limited to 125 gr. .357 rounds and stamped on the barrel "125 gr. bullets only". I still have one. After that they lengthened the frame window to allow a longer cylinder to fit. The longer cylinders were not any "stronger" than the .38 cylinders, just longer. The original .38 cylinder had enough steel around the chambers that they could withstand some pretty serious pressures. Even a Ruger can be blown with a heavy enough load but you really have to push it to make it let go. I have a Kuhnhausen Ruger shop manual with photos from tests that Ruger had done where they plugged the muzzle with a threaded rod and fired proof loads until the barrel was filled with bullets along it's entire length. This was done at an independent lab in a blast chamber to contain the shrapnel if the gun came apart. None of the barrels ever blew. In the photos they cut the barrels lengthwise on a bandsaw and you could see all of the bullets crammed in there. They also did this with a S&W and a Colt revolver. They both blew after a couple of rounds. This was done to dispel all of the rumors that Ruger's casting techniques were not as "strong" as a forged part. Even with all of this strength I see no need to load hot .357 ammo in these guns. A good .38 Spl. load is plenty. Going over that you're just wasting powder and creating huge amounts of muzzle flash.
 
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Typically it's not barrels that blow in over-pressure situations that stress a particular gun beyond its design limits, it's a chamber & topstrap.
And, most of Ruger's barrels, including those on the SP, are not cast, to the best of my knowledge. :)

IF you were to overload an SP, it wouldn't be the barrel that'd let go.
Denis
 
Well, that would have been a problem but anything longer than a 125 gr. would not allow the cylinder to close. The cylinder was simply too short as was the frame window it sits in. Careful handloaders could vary seating depth a little but there was only so much space. With these guns though you really don't "need" a hot .357 load. A hot .38 Spl load will do the job fine if it goes where it needs to and the gun will stay tight for a long time. I have experimented with 140 gr. and 150 gr. cast slugs and I think they're about perfect for a snub revolver. Very good terminal ballistics without beating up you or the gun and are very easy to shoot from an SP. And if your brass is properly sized and properly expanded bullets will not pull. Mass produced factory ammo from a high speed production loading machine? Probably.;)
 
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Did they beef up the frame at all after that change, or was it just lengthening the cylinder window?
Thinking about a 3" .357 SP101 to complement my 4" adjustable sight GP100. I load pretty tame. A 158 LSWC @ 950 fps is plenty for me and my wimpy hands.
 
They just lengthened the frame and cylinder. The design was already plenty strong enough to deal with .357 ammo. Just short ones. I happen to think the SP is one of Ruger's best designs. It's extremely stout for it's size. Just like the GP and Redhawks. A 158 gr. bullet @ 950 is a VERY good load. That is pretty hard to beat IMO. Try some 140 gr. bullets if you can find them. The factory grips are pretty good but the Hogue Monogrip makes it even better. (unless you just can't stand the finger grooves)
 
Thanks drail.
I'm kinda' stuck on the 158 LSWC for my major load but I like the 148 wadcutters @ 800 fps for light practice. My GP came with the Hogues, but I'm buying a set of original rubbers w/inserts. The Hogues are very comfortable, I just like the looks of the originals, we'll see how they shoot.
 
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