1965 Super SS mag cylinder?

[blkhwk741]

Hello everyone. New Ruger member here, but I have owned a variety of Rugers over the years.
I need definitive help in identifying a cylinder as either a .22LR or magnum !
Previous owner always shot .22LR. I shot 36 rounds of .22 LR and something is not right. I believe it may be a magnum cylinder.I won't fire it again until I am sure.

It is a Ruger Single Six that was shipped in 1965. Serial number of pistol matches the number on the original box, and matches the last three numbers that are Etched on the forward face of the cylinder. All six chambers of the cylinder appear to have a visible line closer to the forward face, a 'step down"? Micrometer readings of all six chamber, front and rear appear to bear this out. There is no rimfire grove around the circumference of the back side of the cylinder.
Is this a Magnum cylinder???
Any definitive help is appreciated. Thanks in advance

 

[street]

Yes that is a Magnum cylinder. As it doesn't have the rim fire groove around the back of the cylinder, that is the only way to tell if it is the Magnum cylinder with the old models, just by looking at it. Ruger didn't start making the Magnum cylinder that is non fluted and stamped with .22 Magnum until 1975 for the blue guns.

 

[grayelky]

A magnum round will not go into a LR chamber, but a LR round will drop into a magnum chamber, it just won't seem like it fits right, cause it does not.

 

[blkhwk741]

Thank you very much for your prompt and knowledgeable replies

 

[Richbaker]

Magnum round has a normal bullet that sets inside the case. LR and lesser use a heeled bullet which has the same od as the case. Thus, the magnum cyl has the step in it.....

 

[dakota1911]

You know. I have never shot .22 out of the 22 Mag cylinder of my convertible. Interesting.