Here is the completed front takedown screw and bushing.
My hope is that by fixing the lower flange (the top hat section on top) precisely into the bottom of the stock and the machined recess into the receiver I will create a solid and accurate fix between the receiver and the stock in the front.
I bought a couple of inexpensive, hand made milling vises years ago to use as simple vises to hold parts when drilling in the drill press - something they've been useful for but not designed for. This is actually what a milling vise is for - milling. By being small and precise it can be held in the larger jaws of your main vise and allow you to hold parts in a way that isn't possible otherwise. In this case the long receiver can be held vertically while I machine the slot for the tang to fit into.
This is pretty hard to see but the shaft here is holding a reverse countersink. The arm extending in is a magnet tool that I'm using to hold the bit as I feed it onto the shaft. Because of the design of the receiver the only way to countersink the screw that holds the tang is this reverse countersink that you lift up.
Doing all this to the numbers makes for a very, very tight fit on the tang. I was still seeing some light when the tang was tightened and realized that the receiver is actually an imprecise casting and that there was a high spot that prevented the tang from being snugged down. I few strokes with a file and it was flat.
There's a lot of calculations to get the tang on correctly, to get the pillar the right height and to open up the stock the right amount to fit the tang. Each one relates to the other and I've been doing a
lot of double checking. The receiver, the part that I'm working on, is the part of the gun that has the serial number and as such is "the gun" as it were. If I mess this up I don't have a gun anymore and would have to buy a new part which means all the paperwork, background checks and stuff - not a big deal but a lot of hassle and expense for a math error.
To hold the stock I made a block of baltic birch the size of the receiver to allow me to clamp the stock in the vise and because of the shape I'm having to hold it a bit higher than I'd like. The right thing to do would be to move the vise to the end of the table so I can hang the back of the stock off but that means a LOT of retramming. So I make sure it's good and tight and then machine a 5/8" slot into the back of the stock to allow for the tang.
So far so good. I needed to machine a bit of wood from under the front of the receiver to get everything to lay flat but it looks good.
The rear tang is held by a embedded insert. Kidd gives you one but it didn't look very strong or have much engagement so I bought a few different ones. I'm using centers taps and cardboard shims to hold the tang in place and drill the hole. My first attempt didn't go well.
For some reason, despite my best efforts, the drill wandered off center. Or the stock wasn't perfectly vertical. I wasn't happy with the threaded inserts and gave up and just over drilled the hole knowing the epoxy would hold the insert.
Now to the actual "bedding" part. I have containers of PC7 but in the gun world Devcon 10110 Epoxy Putty is considered the best material. I want to limit the experimentations so I bought some. You can see the receiver is now packed with white clay (thanks Lucas and Nadia!) so that the epoxy doesn't get into any recess. If there's any indentation or recess in the receiver the epoxy will conform and create a "lock" on it preventing removal. Bad. The other thing you do is coat the receiver with clear shoe polish as a release agent.
Devcon 10110 is mixed 9:1 by weight making it different than anything I've worked with before. I don't have photos of the application because I didn't want to get my Leica sticky with epoxy - dusty I can handle, dirty I can deal with but a sticky Leica is a bridge too far.
I'm only putting epoxy on the back end of the stock and in the rear tang area and then under the front stud. Basically reinforcing the two connection points with a new, custom made bed that they will precisely rest in - a perfect fit we hope. The Festool clamp is holding the rear of the action down because right now that insert is floating in epoxy.
It looks and feels like a hot mess at this point. I've covered the stock with tape to prevent epoxy from squeezing out all over the place and made a dam of foam under the bottom of the receiver to help keep that clean. This is when I discovered a mistake in my machining. The front stud that I made had rings to hold epoxy but I didn't create any relief or cut outs for the epoxy to escape when the stud was pressed in. My fits were too precise and the stud basically hydro locked when I pressed it in. I was worried about trying to take it apart so I just kept steady pressure on it hoping it would slowly squeeze out the epoxy and make the right fit.
Twelve hours later I took out the bolts and pried the receiver out. It was I would say a 95% success. The front stud did not make complete contact to the receiver but the epoxy did create a solid bed. It fits perfectly despite this and the lockdown is extremely solid.
The last thing to do was to use a ball end mill to clear out any spots that the barrel touched the stock. This will "free float" the barrel letting the bedding do the work of holding everything in place. The barrel clamp on the front is now just a decoration.
The only thing to do now is take the gun to the range and see if it shoots better than the 1/2-3/4" groups it used to shoot.
While a true test would be at 50yds I only have access to our clubs 50' range but the groups, the lower circled groups are 10 shots and the upper three are five shots, are pretty impressive. It's grouping less than a 1/4" (measured center to center) at 50' and considering that the barrel and trigger are both stock, the whole gun is in fact still stock, and the only change was the bedding of the action, well, I'm pretty pleased.
Total cost of parts is $25 (although epoxy was $40!) and while it was a bit time consuming it was certainly a fun process and one that I'll be able to improve on for the next stock. While Lara's 10/22 is no longer "stock" it's sort of better in that it's a complete sleeper.
I can't wait to get the next one going and see if there's improvements to be made with a better barrel and trigger and to fix my mistakes on the bedding process. Then I need to find some cross country skis!
Gregor
Mine is not mounted. Needless to say mine moves.
