Return to Sauerkraut's Camp Fire Lots of Great Information there!Winchester (Rossi) ’92 Right Side Cartridge Guide Adjustments
Sauerkraut, El Pastor Apestoso
September 8, 2005
Back on 12 May 2005 I made the following post on the SASS Wire:
“I have a Rossi 92 is 38Spl/.357 Mag. It works flawlessly with any .357 Mag. ammo I use. But when working the action fast with .38 Spl it "flips" the loaded round up and out of the receiver and onto the ground before the bullet gets close to the breech. It works OK if I work the action real slow. I'm using the same bullets, 125 gr. TCBB Laser Cast, in both types of ammo. Any suggestions on how to fix the problem so it will feed both types of ammo OK in this rifle?”
I got many replies. One, from Nate Kiowa Jones, was really helpful. He suggested that the problem was due to excessive gap between the left and right cartridge guide rails and the solution was to install shims behind the right guide rail to reduce the gap to the point where the cartridge case would almost, but not quite, touch the guide rails when the cartridge is being fed into the chamber.
So I made some shims from paper card stock. When I installed enough of them the problem ceased: i.e., all .38SPL and .357 MAG ammunition that I tested now feeds fine.
However, I still wasn’t happy. I didn’t feel that paper shims were a good long-term solution. So, I decided that make them from brass shim stock that I obtained from a local hardware store.
The required shim shape is a rectangle about 3/16" wide and 1-3/8" long and with a 9/64" hole 1/2" from one end. The hole is to allow passage of the screw that attaches the rail to the receiver.
Discussion of shim thickness, shim fabrication, and shim installation without disassembly of the rifle follows.
Tools and materials that I used.
Dremel MotoTool, Dremel #125 high speed cutter bit, ice pick or equivalent, "dental" picks, square end tweezers or forceps, screwdriver, wood or plastic wedge, shears or paper cutter to cut shim stock, brass shim stock in assorted thicknesses (K&S shim stock assortment), dial calipers,.
Determine shim thickness requirement.
Per SAMMI, .38/.357 maximum case diameter is .379". The object of the shim is to reduce the gap width to a few thousandths of an inch greater than this value. My experience indicates the optimum gap is about .382" - .386"
To measure the gap between the guide rails open the bolt (lever). Using the dial calipers measure the gap between left and right cartridge guide rails at a location about 1/4" to 3/8" aft of the forward end of the right side guide rail. Subtract .382" from this measurement. This will be the thickness of the required shim. One of my rifles required a total shim thickness of .021".
I now use brass shim stock and I have an assortment of thicknesses: .001", .002", .003", & .005" that I got at a local hardware store. I have used paper card stock which is available in .005 and .007" thicknesses.
I get good cuts of the shim stock using a paper cutter. I can also get good cuts using a pair of heavy scissors. You could also use a pair of good sheet metal shears.
Shim width should be at least 3/16" but no more than .200". Length should be 1-3/8" to 1-7/16"
You will need a 9/64" (.141") hole centered on the shim at .50" from one end.
The way I make the hole is to place the shim blank on a piece of wood and use an ice pick (or similar device) to punch a small hole at the desired location. I then clamp the shim to a piece of wood and use a conical shaped Dremel tool bit (#125 high speed cutter) to enlarge the hole to the desired diameter. I place a piece of flat steel bar stock about 1/8" thick near the edge of the desired hole and clamp it down on the shim using my left index finger. I then use my right hand to hold the Dremel tool to drill the hole. Be careful – it is easy to make the hole too big and break the shim into 2 parts. You will need to de-burr the edges of the hole to maintain the desired shim thickness.
Open bolt (lever).
Remove right guide rail screw.
If necessary, use a dental pick to pull rail out of guide rail slot. The rail will fall on top of carrier. Turn rifle over and the rail will drop out.
Push the cartridge carrier down.
Lay rifle on its side so you can see the slot.
Put a dab of grease in the slot where the shims will go. The grease will help hold the shims in the slot.
Using a pair of tweezers or forceps slip shims into slot. The end with the hole goes aft (towards the butt stock).
Push shims to the bottom of the slot. You can use a dental pick to push the shims down.
Use a dental pick or drift pin to slide shims into alignment with rail screw hole in receiver.
Install guide rail into slot. I grasp the muzzle end of the rail with pair of square tipped tweezers and slip the stock end of the rail into the slot near the face of the bolt. I then remove the tweezers and use a dental pick or drift pin to slide the rail aft.
Install a wedge to lightly “clamp” rail in slot. I use a piece of 1/2" square wood about 2" - 3" long. Carve a taper on one side on one end to make it wedge shape. The taper should be about 1" long and the thickness of the wood should be about .30" at the thin end of the wedge.
Use a pick or brass drift pin to align shim and rail holes with hole in receiver. Be careful so you don’t damage the threads in the guide rail.
Tighten wedge to force it tightly into slot (push it in firmly).
Measure gap – it should be about .382" - .388".
Depending on the exact contour of the bottom of the slot you may have to increase or decrease the amount of shim required to get the desired gap.
Test fire the gun to ensure that your .38 SPL and .357 MAG ammo feeds OK during slow and rapid fire.
I have made this fix on all three malfunctioning rifles and they all work fine now using .38 SPL ammo loaded to an OAL of 1.440" with truncated cone flat point bullets and .357 Mag ammo loaded with the same bullets.
I haven't tested these rifles using shorter .38 Spl ammo because this would cause improper location of the crimp groove. Minimum SAMMI OAL for 38 Spl is 1.400". Someday, when I have nothing better to do I'll load some ammo at the 1.400" OAL and test it to see if it also feeds OK.
This fix caused no degradation in the “smoothness” of my rifle’s action.
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