SP design change

[ruger22]

I thought I posted this, but can't find it. Short story, I got my SP101 .357 as even trade from Ruger for a bad LCR in late March. It has a new design in the area below the crane release button. You can also see the newer tapered cylinder.



You'll see a groove to access the crane button pivot screw. I've only seen one other SP like this, in a LGS a few weeks ago. Ruger confirmed the change, and said I'll see more as the last version is sold off from the warehouses. I guess it will be on all calibers.

The frame lug on SPs started out as a D-shaped bump. Then a rounded strip along the edge of the cylinder window. My .22 SP is like that. Now this triangle shape. They all seem to work equally well.

[ruger22]

A while back, I wondered over the new frame lug design on the SP101 Ruger sent me to replace a LCR :



I looked over my two SPs, and some forum posts today. It dawned on me how the SP frame lug machining works for both centerfire and rimfire. This applies to both lug designs, although I think I like the previous design better that's in the next two photos. On either design, the small bump at the very bottom stops the centerfire cylinders :



On the .22LR model, the cylinder barely clears the recoil shield, because of the countersunk chambers. Then they machine the small bump off, and let the longer straight edge stop the cylinder :



The original SP lug from 1989 :



This is the original 6 shot .22 SP lug, machined narrower than on a .357 :



All this confirms my idea that all SP frames are the same when they come out of the casting mold. The initial machining sets which sights and caliber they'll have.