Starting Repairs
Well, with prompting from other cgn'ers, I got this show on the road.
First item of business, removing the little lock collar that's deep inside the front half of the bolt body. As I have already drilled out the plunger/connector pin that runs between the two parts of the bolt, and it doesn't seem enthusiastic to budge, I cut it.
Big Mistake. It took me most of the day to correct what I did, and while I learned lots, I could have been smarter by doing (and not doing) a few things.
After I cut the pin, this is roughly how the bolt looked. For the sake of chronological order, ignore the little pin above the bolt and that black spec... I tried to fake a pic I forgot to do earlier
Note that the cut was made close to the front bolt half section, so that when the plunger broke/was cut through and the spring released, I was free to access the lock collar with a screw driver.
Unfortunately, I later discovered (while removing the back half of the now un-grippable plunger) a better method. This lifts the rear half of the bolt body free of the plunger, and if the jaws are left slack, will not mar the plunger. If it is scratched, repair with a fine flat file and sand paper will smooth things out.
Once cut and unscrewed, this is what I had:
Note the itty bitty black speck to the right of the firing pin, near dead center of the rag? Turns out that's what what causing all the problems. It had wedged itself next to the firing pin when it's retaining pin had fallen out (creating a hole, which the sand entered, then jammed, stopping the firing pin from falling out, but also stopping it from reliably functioning... Hence why it would fire occasionally, when this little speck of rock was aligned just right
. Also accounts for the scratchy noise I heard.)
Next step was to find a piece of stock metal similar in diameter and length to my now buggered/cut plunger. I found a piece in the shed:
Next step was to remove the fake chrome coating and trim it a little closer to size. Cut the plunger to roughly double what the plunger will be in the end. I used a hand drill simply because I could get more rpms out of it. A medium metal file and 250 sand paper were used as well (remember to sweep the file across the piece so you don't wear a hole in your file
)
Next - I completely forgot to take pictures of.
I held the plunger in vice grips and heated the tip with a propane torch to red hot. I then submerged all but the tip that I was going to be working in cold water to avoid the pin bending when I struck it. ( It makes it easier to work if you have a bucket large enough to get the plyers into, you grip the pin midway up the pin, and tap rather than beat the pin.)
I worked the tip to flare it outwards into a mushroom shape, turning it, and changing the angles of the hammer blows to flare it equally. I had to heat it three times to get it to my satisfaction, and still bent it as I rushed and didn't fully cool the rest of the plunger in my haste before hammering.
In the end you get a rather unsightly uneven flared tip to your plunger. It should be flared larger than the original plunger head, as it will be ground down.
Because I don't have a lathe or a mill, this step instead used a drill press. I mounted the plunger, flare tip exposed in the press. Once turned on I swept the file against the drill rotation, squaring off the head. Then I formed a shoulder where the spring would press against the back of the head by using the file to cut into the flared section of bolt about 2/3 a cm back. As the plunger was a bit bent, I then worked my way up the entire plunger, smoothing it until there were no dark oxidized surface, showing that it had been mostly smoothed and flattened out.
Here's how the pin fitted after the drill press.
I wanted as much energy as possible striking the firing pin, so I left a hairs gap between the front and back half of the bolt. Here it looks way wider than it is:
And ready for firing pin to be fitted and a tool to be made to replace the locking collar thingy (not today).
