Winchester model 67A: here's how to repair and mount a scope on Winchester's model 67A rimfire rifle.
The Model 67A was made by Winchester from the mid 1930s through the 1960s, replacing the Model 60 in an effort to reduce production costs. The .22 Short, Long, and Long Rifle target variant to this gun is the model 68, which came with a hooded front sight and an aperture rear sight. Later, the Model 67 rifle could be purchased with the same sights as those offered with the Model 68 target rifle. Many parts made for the M68 will fit this rifle, however, be aware of .22 WMR (Winchester Magnum Rimfire) versions and order the correct parts for your particular job.
The customer had assembled a mock up of what he wanted on his M67A by securing the scope he wanted mounted to the top of the rifle with zip ties. And although the firing pin seemed to be operating properly, he provided me with a newly-manufactured replacement for fitting and installation since the original was shattered at the rear of the firing pin body. The customer also said he'd like to able to mount other optics one day so his grandson could grow into this starter gun.
With this information in mind, along with the provided scope, ring/mount, and new firing pin, I headed to the workbench to examine what he had envisioned. I did some research on potential mounting solutions for this particular make and model of rimfire and was a little surprised to find that no one makes a scope mount or scope base set specifically for this gun, other than some aftermarket side mounts. The owner was clear that he didn't want a side-mounted scope as that type of mount can preclude making changes or upgrades to optics options down the road. I did see a one-piece base that was once available from a well-known parts house but it was made for the M68 and was no longer available from them at the time of this repair job.
I began looking at using Weaver and similar bases, checking their charts for specific rifle mounting combinations, and I found there was no such animal for this particular model. I also was unable to find a schematic or any other information pertaining to the gun, other than a little historical information about it. I measured the diameter of the "receiver", which on this rifle is also the barrel as it is a one-piece barreled action. I held the scope to be mounted over the top of the receiver area so that I could get an idea of where the scope should be placed when shouldered.
Once I determined proper placement of the scope, I marked the barrel where the two bases would need to go, then measured the receiver diameter at these two locations (between the breech face and the rear sight dovetail) to determine if Weaver had a suitable base with nearly the same base diameter as where they would be attached to the receiver. Based on the measurements, I found the Weaver Model #17 base had a diameter that would fit perfectly on this receiver at both locations, so two were ordered. The receiver had an approximate diameter of 0.790" at both mounting locations and the #17 base lists a diameter of 0.770", which would mate to the barrel quite nicely.
Now for the fun part! The round receiver/barrel made it a little difficult getting it square and plumb with the bore in my sight drill jig. I first assumed that the two cuts in the receiver where the bolt handle closes would be the leveling alignment area, however, I quickly found that not to be true. Leveling from those two points in the jig left the sights at a slightly off-centered right angle. I removed the rear sight from the dovetail and leveled the barrel/receiver with the flat of that dovetail. That did the trick. I figured the factory had to align the barrel/receiver plumb to make the two dovetail cuts in the barreled action for the sights. To be certain, I removed the front sight and checked it as well.
Once I found true perpendicular alignment of the receiver and bore, I placed a clamp-on barrel level near the muzzle and set it to level and in agreement with the dovetail levels. This worked quite well. Finally, I checked the sear/extractor still assembled in the receiver/action and the stock stud dovetailed into the bottom of the receiver for plumb. Both were square and plumb with the level.
With the barrel/receiver true with the jig and secured in place for drilling and tapping, both sight base locations were marked where the bases would be installed. I leveled and plumbed the fixture in the mill, spot checking each marked hole location prior to drilling. The holes were tapped and the bases were installed with each screw given a dab of blue Loctite. Although a rimfire lacks recoil, I have found over the years that rimfire guns are handled rougher than a prized hunting rifle and bumping and knocking around can dislodge screws or bases. Loctite is easy insurance.
With the bases mounted and my previous customer conversation, I topped the bases with adapters mounting on the Weaver rail providing the capability of clamping on 3/8" dovetail rings or mounts. Since the customer was starting with mounting a rimfire scope with 3/8" dovetail-type rings, it seemed to be a logical choice. When the adapters arrived, I found them to be a bit longer on each end than the bases, so I filed and trued up both ends flush with the bases when mounted. The bases are 0.812" long and the adapters were 11/8". Resizing the adapters made for a clean look when secured to the bases without any mounting compromises. A quick spray with Brownells Aluma-Hyde II in semi-gloss black finished the look.
The adapters were a good choice for this installation, increasing the overall mounting height of the scope and leaving no need for additional work to achieve proper bolt handle clearance. The only drawback is the 3/8" dovetail does not center perfectly over the Weaver bases. When the scope is installed it doesn't appear to be in proper alignment with the barrel, but this doesn't impact accuracy and the very small amount off-center appearance doesn't detract looks too badly. The dovetail adapters and Weaver bases allow a variety of optic choices, including larger one inch or 30mm tubes, a scope with a 40mm objective lenses, or a various sizes of electronic optics as there are a variety of Weaver rings (high, off-set, see-through, etc.) that can be used to secure a chosen optic. This made for a very versatile mounting system.
Since I was unable to locate a schematic or any disassembly instructions for this make and model rimfire, I decided to add it here. Let's begin by checking to ensure the gun is unloaded (physically look in the chamber), then remove the bolt by pulling the trigger all the way to the rear to release it from the receiver. If you find that the bolt seems to be binding or not coming out, don't force it to the rear. Push the bolt forward, then reopen it slowly and only pull the bolt to the rear enough so that you don't dispatch the extractor/sear. Pull the trigger and remove the bolt. If the extractor/sear moves back from the breech too far, it prevents the trigger from being able to lower the extractor/sear enough to clear the bolt during removal.
With the bolt removed and set aside, unscrew the stock stud screw and lift the barrel/receiver out of the stock by tilting it up at the muzzle enough to get the stock stud clear of the stock, then pull the barrel/receiver forward and out of the stock.
The reason for this is that the extractor/sear stays in the receiver and is held in place with a flat spring while the trigger stays pinned in the stock. The two must be separated from each other by lifting and pulling the barrel/receiver out of the stock and forward. With the barrel/receiver out of the stock, note how the trigger is pinned inside of the stock and has a coil spring behind it serving as the trigger return spring. The barrel/receiver gets reassembled into the stock as the extractor/sear "hooks" onto the trigger so that it can operate properly when the barrel/receiver is assembled into the stock again. The extractor/sear must come down when the trigger is pulled to release the firing pin.
To remove the extractor/sear, pull on it downward and towards the rear and it will come out as it is retained in place by the flat spring attached to the bottom of the receiver only. The extractor/sear (flat) spring can be removed by tapping it towards the rear while lifting up on the turned down end of the flat spring, allowing it to move out of the cut in the receiver. The flat spring moves rearward and lifts off the stock stud. Assembly of the extractor/sear spring is in reverse. This completes disassembly of the barreled action except for the front and rear sights. If needed, both can be removed by drifting them from their dovetail slots from left to right.
Turning our attention back to the bolt assembly, begin by carefully pushing the firing pin guide pin out through the bolt body with a pin punch. Do your best to push the pin out by hand or a few gentle taps with a brass hammer. Giving the pin a hard whack risks breaking the fragile rear sides of the firing pin body. The firing pin guide pin rides in the firing pin guide slot. Once the firing pin guide pin is removed, back the bolt "guts" out of the bolt body in one piece by pulling back on the cocking knob, officially known as the firing pin head. Keep an eye out for the round safety lock friction ring that fits on the firing pin body just ahead of the safety lock as it is housed inside of the bolt body.
With the bolt body removed and the safety lock friction ring set aside, further disassemble the bolt by sliding the safety lock forward and off the firing pin body. Remember, the safety lock was in place for reassembly. The "wing" or safety lock tab will be reinstalled so that it is upward in relation to the bolt handle. In other words, when the bolt is fully assembled the safety lock wing or tab should be positioned at the 3 o'clock position when the safety lock is in the off position and in the 12 o'clock position when the safety lock is on and the bolt is closed and cocked.
With the safety lock removed, use a pin punch to drift out the firing pin head pin that holds the cocking button (firing pin head) onto the rear of the firing pin body. Again, go slow and gently here and do not force the pin out. Too much pounding can damage or break the rear of the fragile firing pin body at the firing pin head pin retaining hole. Gently tap the pin to free it up and ease the pin out, then pull the firing pin head out of the firing pin body. There you'll see a small coil spring inside the firing pin head called the firing pin retracting spring. This small coil spring presses up against the back side of the firing pin guide pin and the firing pin spring and guide (bushing) presses up against the front of this same pin. Remove the firing pin spring and guide from inside the firing pin body. Note, the firing pin spring guide goes to the rear of the firing pin spring when reassembling and will press up against the firing pin guide pin. Replace these two springs if needed.
If you are installing a replacement firing pin (as in the case of this particular repair job), make sure the firing pin has no sharp edges and moves freely inside of the bolt body housing. Check the length of the protruding end of the firing pin does not go beyond the far end of the bolt face area, basically ensuring the firing pin will not impact the back of the chamber when the trigger is pulled or gun is dry fired. Once the firing pin is installed properly, reassemble the bolt. Begin by inserting the firing pin spring and guide back into the firing pin body with the guide towards the rear of the spring. Next, make sure the firing pin retracting spring (small coil spring) is still in place inside of the firing pin head and insert the head into the rear of the firing pin body. Align the firing pin head pin hole with the hole in the rear of the firing pin body and gently reinstall the firing pin head pin. Don't force it or you will break the rear body of the firing pin. Go slow and make sure the pin is not binding while reinserting.
Now that the firing pin head is installed on the firing pin body, slide the safety lock back over the firing pin body from the front and pull it fully to the rear. Make sure to position the safety lock so the wing or tab is in the up position with respect to the pointed end of the firing pin. In other words, when you insert the firing pin into the bolt body, the firing pin nose should fit into the bolt face and the safety lock "wing" or tab should be in the upright or 3 o'clock position with respect to the bolt handle. Before going forward, replace the safety lock friction spring (round spring) onto the firing pin body and up against the safety lock. With this together, install the very first pin removed--the firing pin guide pin--through the bolt body. This can be tricky. I recommend using a slave pin, aligning the firing pin head pin hole with the bolt body and safety and safety lock. Insert a slave pin in the hole between the firing pin spring guide and the firing pin retracting spring inside the firing pin head.
Once the slave pin is in place, align the pin holes in the body with the firing pin guide pin hole cutout (where the slave pin is now) and install the pin while pushing the slave pin out. Gently tap the pin into place to secure it. That completes the bolt reassembly. Check to make sure the safety lock wing is either at the 12 o'clock or 3 o'clock position with the top of the bolt body.
With the bolt assembled, return to the barreled action. Install the extractor/sear flat spring over the stock stud and lock into place. Install the extractor/sear into the receiver cutout by pushing the extractor portion in first under the flat spring then forward to seat it into the receiver. If you have not already reinstalled the dovetailed sights, do that now. Once the barrel/receiver is back together, insert the rear of the receiver into the stock first by angling the rear of the receiver downward towards the stock and sliding the extractor/sear "hook" onto the trigger arm that is pinned in the stock, essentially engaging the two. Push the barrel downward into the stock channel and start the stock stud screw to somewhat secure the barreled action into the stock. Test the trigger to make sure it is pulling down on the extractor/sear properly, and if so, tighten the stock stud screw.
Install the bolt. Pull the trigger rearward and slide the bolt into the action. As stated earlier, you may find that the bolt won't go in for some reason. If that occurs, push the extractor/sear forward so the extractor is up against the back of the barrel breech, then install the bolt after pulling the trigger rearward. If the extractor/sear is back to the rear, it will prevent you from pulling the trigger back enough for the extractor/sear to move down and out of the way of the bolt to fit fully into the receiver.
This was pretty much a straightforward firing pin repair and scope mounting job, with a couple of unexpected obstacles. The use of Weaver bases allowed the customer to have additional options of mounting different sizes of scopes or electronic optics to the rifle base mounts. Hopefully, this information will help you too, when one of these old, nearly forgotten rimfire rifles finds its way to your bench.
by Mark R. Hollensen
|Printer friendly Cite/link Email Feedback|
|Author:||Hollensen, Mark R.|
|Date:||Sep 1, 2017|
|Previous Article:||M1 Carbine: an overview of the iconic united states military issue personal defense weapon of world war two.|
|Next Article:||Checkering gunstocks: a gunsmith's overview of how he checkers a stock.|