I think Winchester put a rib on a couple smoothbore 61's during their production. Maybe it was just that they matted the top of the bbl. Confused myself again....
Should be in that book on the Winchester slide action 22's that features the 61.
A 1/4 rib would look nice I think.
I believe that book was written by Ned Schwing. I didn't know the M61 was offered in a smooth (Rutledge?) bore. I can also see some slight resemblance between the M61 and the M42 in .410 bore. Now a solid rib on a M42- like a pinkie ring and an Armani suit on a "Goombah"--
The M61 was made in 3 different smooth bores actually. The original Routledge bore first.
Winchester then designed their own version of the counterbored system and used that next (not having to pay Fred anything for his design). It was simply some small changes in the counter bore diameter and depth.
Then lastly they made the M61 22 Shot with just a straight thru one diameter smooth bore bbl.
I think Simmons was used to put the rib on what ever smoothbore 61s the factory did make. Those were Vent Rib style and IIRC they extended back onto the recv'r like the same would on a 12 or 42.
I wish I could find my books.
The bbl address roll mark on 61's is off to the left side on the round bbls (left oblique flat on oct),,so if you are able to get a narrow enough solid rib, you can by-pass those markings and leave them as is on the bbl.
A narrow, low solid rib would look nicest anyway.
Some of the M61s have the front edge of the recv'r severly chamfered. Running a squared edge rib up against it may leave it unsightly unless fitted very low ,below the chamfer.
The other way is to build up that small top portion of the frame to elliminate the chamfer and have a nice square flat for the rib to engage the frame front surface with.
I don't know who's making ribs that would look right.
I have seen some made from M/L under bbl rib stock. The M/L rib flipped over and the ramrod groove becomes the bbl side of it.
Lots and lots of fitting & reshaping work and heavy when done. Depends on what you're looking for.
The older hollow rib M/L under rib might be an easier go of it. Lighter for sure. I don't see much of it sold anymore though.
Fitting up to a 61 bbl for either would be much easier than say a center fire bolt rifle bbl with it's contours.
Just some thoughts
...I like the 42 w/a solid rib ! I've got 2 of them :>)
