Better looking SKS
Posted: Sat Feb 27, 2016 9:20 am
This is a reliable shooter that has the common limits of iron sights. I like it generally because with the heavy bullet weight it is a good brush gun, and can out range the .223 in most cases. The problem is, there is no good place to mount any optics to improve your sight picture. If ya cant see it, you aint gonna hit it. So in the interest of gun control, I have been looking for an answer to this question. I found in my local gun store a spring block that covers the receiver and serves as a replacement to the bolt shield. It has a Picatini rail made on top, but has to be fitted to each gun, due to the generic design drift of the various manufacturers. My particular SKS has all machined pieces instead of bent sheet, excepting the 10 round integral ammo clip. When removed it will handle extended clips from beneath.
So, we begin work with stripping the spring block/receiver cover, by taking out the rear pin, that has a lever on it. Swinging it vertical, and sliding it to the right releases the block, and it come up and away from the breech, with the bolt return spring coming out full length. we now take the spring, two sliding bolt parts from the track, and the entire breech is clear. This is a simple mechanism, and hard to screw up, but is reputed to be fragile with short life from wear.
With the receiver clear of clutter, we can now start to fit out the new cover and sight mounts. As predicted, the block and pin hole are too far to the rear of the receiver, and must have it fitted forward about 1/16 to get the block to align with the rear of the action near flush, and get the machined cross pin to align.
i started in with a large Mill file, a sharp one, and began working the tapered end that fit under the ramp in the receiver to draw the entire piece forward. About two hours were spent in file and fit, so that angles and gaps remained true. Once the rear dimension showed a nearly perfect fit across the rear, it is discovered, the pin hole is still further back, more than a 64th. Since the pin hole has a key hole cut in it as part of the lock mechanism, just running a number drill through the hole will pull the hole out toward the missing material of the key hole. Drilling through the receiver, promises to oval the reciever holes, with undesired drift. For accuracy, this hole is critical to keeping the spring block tight in place, and movement under the scope is not an option. So in further checking, I reversed the cover, and found the pin will NOT slip through the hole. it is too small. So, what next.?
When working around guns, I tend to modify the added pieces, and leave the base features alone, so as to retore the gun to original profiles if my work , doesnt work. So it is with this. Since this rather aggravating fitting operation is now focused on a single hole, I have elected to use a Dremel and grinding stones, to move the hole forward for the final fit. by work holding the piece in a vertical alignment, I can control the stone to go straight down, and shift the hole the needed amount, while getting the pin size on dimension for the snug fit needed, to prevent rattle type movement. My margin of error is such that if I blow the dimensions of the fit, I lose a $40 gizmo, that can be replaced, for attempt #2 instead of junking up a fairly new (unused) rifle. More to come.