Ruger SP101 Cylinder Question

[4DSJW]

Saw a first year production SP101 for sale that is a .38spcl only gun, KSP-183. Does anyone know if this cylinder can be bored out to accept the slightly longer .357 mag ammo? Or does this cylinder have thinner walls and won't handle the increased pressure? I'm would think that the rest of the gun will handle the .357 loads.

- could a newer, or any, .38/.357 cylinder be fitted?
- by a home gunsmith without timing it?

Thank you for your help!

[bigbob76]

If I liked it I would buy it and shoot .38 special. You can always buy a .357 also. Sometimes at the range I scratch my head and wonder about what I see some guys doing. They will buy a Glock and start tricking it out to try to make it like a 1911. If they asked I would say "you know you can have a Glock and a 1911, you don't have to try to make the Glock something its not".

[4DSJW]

If I liked it I would buy it and shoot .38 special. You can always buy a .357 also. Sometimes at the range I scratch my head and wonder about what I see some guys doing. They will buy a Glock and start tricking it out to try to make it like a 1911. If they asked I would say "you know you can have a Glock and a 1911, you don't have to try to make the Glock something its not".

LOL, I totally know what you are saying. In reality I would be using .38+P Gold Dot ammo for SD, as I do in my other revolvers which happen to be chambered in .357. Seeing the .38 only chambering just got me thinking, "why a .38 only?", and then the train-of-thought into, "could I ...?)

Thanks!

[ojisan]

Seems that many manufacturers release a new revolver in .38 Special first, then the .357 a year or two later so sales go back up.
Ruger did that with the LCR.

This may not be just marketing, though.
I think the SP was originally intended to "match-up" to the S&W J frames in .38 Special.
Back-up guns for LE was the intent.
Some police departments will not allow a gun that accepts .357 if the approved load is .38 Special, the shorter .38 chambers prevents any .357 use.

I don't think there is any real difference between the Ruger .38 and .357 cylinders other than the chamber length.
I cannot recommend you do this, but if it were mine, I'd be locating a .357 reamer.

The only caveat being that a Ruger collector may want one of these in the .38 chambering, and reaming it to .357 may destroy the collector value.


Cylinder swap...probably would work as a drop-in as Ruger's manufacturing methods want every gun assembled with as-produced parts and no hand fitting.
My guess is the timing will be OK but it must be checked....same for the barrel-to-cylinder gap.
If you order a cylinder, get an extra hand so if your current one is too short you have a longer one to work with.
(But again, Ruger wants all parts to fit with no hand work or adjustment, S&W does still hand fit parts).

[Twystd1]

I don't believe the cylinder is long enough to accept the 357 mag cartridge length.

Mine doesn't.

-T

[ck66]

Saw a first year production SP101 for sale that is a .38spcl only gun, KSP-183. Does anyone know if this cylinder can be bored out to accept the slightly longer .357 mag ammo? Or does this cylinder have thinner walls and won't handle the increased pressure? I'm would think that the rest of the gun will handle the .357 loads.

- could a newer, or any, .38/.357 cylinder be fitted?
- by a home gunsmith without timing it?

Thank you for your help!

There was a shop that reamed out the cylinder for .357 from the early .38 gun, but only 125gr loads. Loads heaver than 125gr were too long and would stick out past the cylinder. Ruger eventually did the same and had a "125gr load only" stamped on the barrel. It wasn't long before Ruger made the frame and cylinder slightly longer to take any normal .357 load. A current .357 cylinder won't fit that first year .38 gun.

[ojisan]

^ My bad, you guys are right.
The first years did have a shorter cylinder.

[kcstott]

Either shoot +P loads or buy a Magnum, theres a bit more going on then just a deeper chamber in the cylinder. There's no guaranty the cylinder is strong enough to handle the pressure even if it was long enough to cycle with the heavier loads. you don't need much to contain 17Kpsi but the magnum is double that,

[4DSJW]

You guys rock! I love this place. A big thank you to everyone for taking the time to help me learn something.

[Nathan Krynn]

Either shoot +P loads or buy a Magnum, theres a bit more going on then just a deeper chamber in the cylinder. There's no guaranty the cylinder is strong enough to handle the pressure even if it was long enough to cycle with the heavier loads. you don't need much to contain 17Kpsi but the magnum is double that,

Winner, Winner, Chicken Dinner. They "might" have made the same cylinder and cut it short, but I doubt it.

I too have a .38 only revolver that I wish was .357 but I like my hands too much to ream it. Darn thing is just accurate as heck though. I use it to teach people the fundamentals of shooting and revolvers specifically.