Ruger single six convertible question

[squawberryman]

Axe you've indicated the mag and the LR aren't compatible in that frame and I believe you. There's a 1965 over on RF. How much further back do you have to go to get what is considered correct? Anyone chime in please.

[Paden]

Jan 25, 2017 16:28:06 GMT -5 squawberryman said:

Axe you've indicated the mag and the LR aren't compatible in that frame...

Why not? Please explain.

[frankenfab]

Is this about the bore/groove dimensions?

I'm curious myself.

[dougader]

Jan 25, 2017 17:46:58 GMT -5 frankenfab said:

Is this about the bore/groove dimensions?

I'm curious myself.

That's what I was thinking.

[JM]

22 Magnum barrel I.D. is slightly larger than 22 LR.

[Encore64]

A bit off subject, maybe. I'd read where Ruger changed the Bearcat barrels to accommodate the 22 Magnum rounds of the convertible model and never went back after they were discontinued.

So, I decided to slug my new adjustable sight models. Starting with the blue gun and some .225" lead bullets that ended up .2237". I can't say if they are all the same.

It could be a similar situation with early Single Six guns.

[frankenfab]

I think 22 LR is supposed to be .222

Using one of the acuurizer tools that swages the projectile would probably make it a non- issue.

[Paden]

So, fwiw, I just slugged my recent production stainless Single-Six convertible:
Bore dia: 0.220
Groove dia: 0.225
Throats in both the LR and Mag cylinder are virtually indistinguishable, all measuring: 0.2255 to 0.2260


SAAMI spec for bullet dia:
.22 short/LR: .2255-.0040
.22 Win Mag: .2245-.0040
saami.org/specifications_and_information/publications/download/Z299-1_ANSI-SAAMI_Rimfire.pdf#page=8


All the various .22 short/LR rounds I have available measure from .2225 on the small end (cheap sub-sonic gallery rounds) to .2250 on the upper end (RWS Target Rifle, and various others).

I don't have any Win Mag rounds available to measure tonight.




As far as my gun is concerned, I could see that hypothetically, if I had some Win Mag bullets which were on the very minimum end of SAAMI diameter spec (.2205), they would appear a hair too small for my groove diameter. But, given the launch pressure of the Win Mag, I would think, unless the bullet in question is exceptionally hard, it will easily obturate to throat diameter and solid engraving into the lands without blow-by gas cutting should be a non-issue. No? I haven't shot Win Mag in this gun yet to confirm it's not going to lead, but I'm not anticipating it will.

[frankenfab]

Another source, for reference

www.rimfirecentral.com/forums/showthread.php?t=618297

[contender]

I'm not exactly sure if I understand the questions,,, but I'll throw in a bit of information.
The Ruger Single-Six was first built in 1953,,, and has a smaller bore diameter for the 22 LR ammo. In 1958,,, Winchester introduced the 22 magnum. When Ruger began making the 22 mag only guns,,, they used a different serial number block AND marked them ".22 WMR." The serial number block started at 300000, and went to 398349. When they decided to drop the magnum only & make convertibles,,, they reverted to the original serial number block,,, and it is considered by collectors that guns built with a serial number lower than 150000 are the smaller bore,,, while the ones built after that will accommodate both the 22 mag & the 22 LR. And,,, when they were building the 22 mag only guns,,, SOME were built with a 22 LR cylinder,,, so it can be a little confusing.
You may find an OM Single-Six that will accept an OM 22 mag cylinder,,, but if the serial number is below 150000,,, I'd not try to shoot magnums out of it.

[2 Dogs]

For some real fun, take several different boxes of 22 LR and put a micrometer on the bullet diameters. You would be surprised at the variation.