No. 1 Quarter Rib

[ebdyguy]

I picked up some miscellaneous No.1 parts from a guy at work and there were two quarter ribs in the box, both tagged as No. 1. One has the front pin centered between the two mounting screws (like my rifle) and one that has the pin offset toward the rear. Otherwise they look to be similar. What version does the offset pin rib fit?


http://i1354.photobucket.com/albums/q688/ebdyguy/Quarter%20Rib_zpst6yd3x8l.jpg?t=1504579200

 

[ebdyguy]

OK - just found another one mixed in - no mounting holes at all - just the mounting screw holes. Neither one has a sight mount on it.

 

[gewehrfreund]

DO you have pictures of all three? The one you linked a picture to is a standard 1A or 1B rib (depending on the radius of the bottom side of the rib and how high it is in the front, top to bottom)

I can't imagine what the others are without seeing pictures, unless they are not Ruger items, or are unfinished/unfitted ribs, and I doubt they'd get out of the factory unless an employee walked them out.

 

[roofinspector]

Later ribs can be marked on the bottom of the contoured side, B, A, S, etc

 

[ebdyguy]

The first rib has a very faint "B" stamped on the bottom. Below is the best I can do from work

I don't want to try to remove the rib from my no prefix gun but it looks like this:

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I can't see any readable marking on the no pin rib

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So 3 very similar finished ribs all with different mounting arrangements. I would like to advertise the two that don't fit my rifle but don't really know what to call them. My rifle is marked as a B, but the rib with the "B" marking won't interchange with my rib.

 

[rowdy1972]

The ramp with the offset hole is off from a newer no 1...dont know exactly when they changed


The one with out locator holes is off from a current no 1

 

[ebdyguy]

Anybody have more detailed information about when the change years happened?

 

[gewehrfreund]

My only really newer No. 1 is a 1A in 222, made in 2013, and it does not have the positioning posts/holes. So the change happened in 2013 or earlier.

 

[picketpin]

!984 at the same time the angle of the receiver/fore arm jumtion was changed slightly. The ribs are not interchangeable without some modification for older pre 1984 versus 1984 on. If you install a early forearm on a post 1984 it leaves a gap. The other way around you have to remove some wood.

Ribs, you have to drill a new hole on the barrel OR a new hole in the rib. I done both. Drilling the rib is easier and you can use a shortened barrel stud and fill the hole for cosmetic reasons. .

When were the studs removed? Beats me but my newest a 264 Win Mag "S" shipp 08-2012 does not have them By the way that has sort of always been an option. My smith routinely left them off when rebarreling and just used (drilled and tapped) to mount the rib and used the pulled studs from the original barrel to fill the holes in the rib.

I'll take a look at the other and see if I can come up with a better guess. "Sadly" the vast majority of mine are "EARLY" non prefix up until early 132 prefix. ;-)

Ross

Hang onto those with the centered (early) pattern. They are getting damned hard to find.