Welcome to Winchester Model 12 ownership and care!
If you are just thinking about getting one, and you will be in the vicinity of St Louis, you can rent one of dozens of beautiful M12's and Super X One's here at the Winchester company-owned club:
It is located in East Alton, IL, right across the Mississippi River, and right up the road a mile from the Olin Winchester ammo plant, where all their shotshell manufacturing still takes place:
After a long delay with no free time to correct the damage Photobucketup did to my OP, I've made some time to do a complete rewrite, using imgbb.com to host the pics, hopefully forever. Everything is brand new, except the gun itself!
M12's are still plentiful and fairly inexpensive these days, with over 2 million manufactured between 1912-1963, and a few after that. Unfortunately, despite that they were pricy in their day, they too often have been left dirty, and many are rust buckets, mine included, thanks to unknown previous owners. It still shoots like a dream, though! 8)
The rust may be because taking them apart to clean them properly is an intimidating mystery to some owners, though as you will see, it shouldn't be. :?
All references are from the butt of the gun, looking forward towards the muzzle, and part numbers and names used, as this diagram shows:
MAKE SURE THE GUN IS UNLOADED, AND THE TRIGGER SAFETY ON, FIRST!
The M12 shown in the assembled and ready to fire condition:
LOCKING AND UNLOCKING THE MAGAZINE -- Separating the gun into two halves, known as "takedown."
The first step of disassembly, (and last the step of reassembly in reverse order,) is to unlock (lock) the Magazine tube (21) ("Mag" hereafter) for takedown. This can be done as often as you like, and becomes second nature with practice, just like an O/U. I keep my M12 in a takedown case, just like my O/U.
The Magazine locking pin (19) ("Mag pin") is shown in the locked, ready to fire, 11 o'clock position:
Note the Mag is fully rearward, (locked and ready to fire condition,) with the Mag pin right next to the Magazine band (14) ("Mag band").
During takedown and reassembly, you must take care for the threads on the Barrel (11) and Mag, and their mates inside the Receiver (1):
Depress the Mag pin to the 5 o'clock position, then rotate the Mag pin and Mag together (the pin is your lever) to the 8 o'clock position, one-quarter turn:
If the Mag won't turn with the leverage provided by the Mag pin and your fingers, you may have grime, rust, or damage, either under the Mag band, or in the Receiver/Mag threads.
IF AND ONLY IF it won't turn easily, first try removing the Magazine band bushing screws (12) ("Mag band screws") (shown installed above/removed below) to allow the band to be spread a little bit wider on the Mag:
The Mag band should never make immovable contact with the Mag, but it does hold the Barrel tight when the two screws are installed, by design. The Barrel is fixed, the Mag is designed to slide forward and rearward through the (snug) Mag band, only when unlocked, to disengage the receiver for takedown.
The Barrel above is shown popped out (the Mag band functioning like a "U-shaped" spring with the screws removed.) This is the normal way the Barrel is LATER STEP separated (and reinstalled ) from (to) the Mag.
Also, the "Barrel flange" is shown, which goes into the Mag band and Magazine band bushing, (13) into mortises cut into them.
As with everything on neglected guns, if something is stuck, soak overnight or longer with penetrating oil. If that doesn't free it up, see a gunsmith. Never use tools which generate excessive leverage. This gun is designed to only need a 3/16th" hollow ground standard tip screwdriver to disassemble.
Assuming the Mag slides freely, slide the Mag, Action slide (25) and Action slide handle (28) ("Slide") forward about 4" until they all contact the "Mag flange:"
The Mag flange's rear edge is the forward limit of travel for the Action slide sleeve screw cap (27).
The Slide, cap, and handle are normally left installed on the Mag. The cap requires a special tool from Brownell's, or a home made one, to remove, and there is no reason to for normal cleaning.
The Action slide (25) bar must be fully retracted from the Receiver BEFORE you attempt to remove the forward half of the gun from the rear half.
THIS WILL CAUSE DAMAGE:
THIS IS PROPER: Action Slide bar fully flush with the Receiver extension (8) BEFORE you try to separate the halves:
Hold the Buttstock (47) and Receiver still, keep forward pressure on the Slide and rotate the forward half of the gun just slightly less than one-quarter turn clockwise, then gently draw it forward and clear of the Receiver, carefully so as not to bung the threads. A good "cheat" is to hold the gun vertically, so there is no side-load on the threads.
The M12 in takedown:
Note again, the difference between when the Mag is unlocked, above, slid about 4" forward from the Mag band, compared to when it is locked:
SEPARATING THE BARREL FROM THE MAG -- It's going to start getting tricky now!
The Mag can be left internally intact or disassembled, on or off of the Barrel, your choice. The exception is if you want to remove the Mag band and Action slide handle retaining (leaf) spring (15) from the Mag. To remove those, both the Barrel/Mag separation and Mag disassembly are required, together, but we'll hold off on that, until we disassemble the Mag.
Once the forward half of the gun is free of the Receiver, set the Receiver aside.
As mentioned above in the stuck Mag band comments, remove the Mag band screws, and "pop" the Barrel apart from the Mag by inserting the fingers of both hands in the gaps between the two parts.
The Barrel and attached Receiver Extension is then set aside for normal cleaning. Leave the Extension attached to the Barrel. Removing and adjusting Barrel tension is only for a well-experienced M12 gunsmith to attempt.
Reassembly will again be the reverse:
Gently place the rear end of the Mag into the Receiver extension
Line up the Barrel flange with the reassembled and installed Mag band and Magazine plug stop (16), (see below, looks like Felix the cat)
Make sure the Mag flange (not the Barrel flange) is at the 9 o'clock position:
Squeeze the Barrel back into the Mag band, by making "fists" around the Barrel and Mag, and slowly closing them.
Finally, reinsert and tighten the Mag band screws. Some may wish to consider Blue Loctite.
This too all becomes second nature with practice, though it need not be done regularly unless the gun gets wet or you want to "deep clean" it.
DISASSEMBLY AND REASSEMBLY OF THE MAG -- Now it starts getting a little complicated! :?
The Mag pin has a small "spring-clip" set into a slot on the side of the pin. One end of the spring is rounded, the other forms a protruding "tip."
Note above, the spring inside the Mag pin has been depressed with a small standard screwdriver (the only tool required) and removed from the Mag, then partially reinserted to show the proper way it is reinstalled, later. It only works one way!
The rounded end of the spring MUST BE reinstalled on the 8 o'clock end, and the protruding "tip" towards the 2 o'clock end. Memory aid: "TIP-TWO" (like "tip-toe")
Next, reverse the Mag pin and stick it back in its hole as an easily removed "keeper," while you remove the two tiny Magazine plug screws (18) (also shown are the Mag band screws)
If you don't do it this way, if the pin is completely removed and you unscrew the plug screws, the Magazine spring (22) will shoot the Magazine plug (17) (not the Three-shell wooden plug (24)) out like a rifled slug of just about exactly the gauge your gun is!
Conversely, if you leave the Mag pin installed normally, and first remove the plug screws, you will have nowhere near enough hands to hold the gun, and the plug, and try to work the pin spring out of the mag...trust me on this!
Then the Mag plug is held by the thumb against spring pressure, the Pin easily withdrawn, set aside, and then the Spring tension is slowly released, covered with the palm of the free hand.
Remove the Mag spring and Magazine follower (23) and clean, swab with oil, and/or replace with a new spring to your heart's content.
My gun was built in 1929, and while I have no idea if this is the original spring, my gun never got a drop of love before I bought it about 5 years ago, and I haven't replaced it. Seems to work perfectly, and I shoot a fair amount of trap, skeet, 5-Stand, and Sporting Clays with it, far more than its previous lifetime total round count, judging by the lack of internal wear.
Next is removing the above-mentioned Magazine plug stop (16), "Felix the cat." It is a ring with two "ears," one for each side of the Barrel. It slides off and on the rear of the Mag plug, obviously. The trick is remembering which way it goes back on!
Finally, now you can slide off the Mag Band, its Magazine band bushing (13), and the Action slide handle retaining spring (15) (leaf-type).
That is the Mag totally disassembled if ever you want/need to do it.
Removing parts on the M12 is easy, but there are several WRONG ways to reinstall them and only one correct way!
First, back on with the Mag band, AFTER you correctly install its bushing; that means the large-side cutouts with threads showing are upwards, towards the Barrel.
Next, slip the leaf spring back under the band:
Now it's time to rebuild the Mag internals:
First, put the Mag follower on the Mag spring, and loosely insert it in the Mag.
Next, the slot in the Mag plug goes on the opposite (right) side of the mag flange. This slot and the gauge-stamped tab on the Mag plug stop ("Felix") is what limits the rotating of the Mag to one-quarter turn.
Before inserting the Mag plug in the Mag, the plug stop is slid over the rear of the plug, with the stamped gauge number on the tab facing towards the rear of the Mag (follower end) and the tab in the slot.
Then, compressing the Mag spring flush with your fingers, the Mag plug is inserted in the Mag, with the plug stop ears pointing up to receive the Barrel.
It is all temporarily held together with the reversed Mag pin again, then the plug screws are replaced and tightened. Some may wish to consider Blue Loctite?
Finally, with the plug screws tight, the Mag pin is withdrawn, and reinserted properly, FROM the 8 o'clock direction, with the "tip-two" (o'clock.) The pin spring is depressed with the screwdriver tip, and the pin inserted.
It now will not fall out (the purpose of the tip,) but it also will cycle from unlocked to locked properly; if it is installed incorrectly, it won't cycle properly, or it may fall out on the ground and could be lost.
The Mag pin is left in the 8 o'clock position until you wish to rejoin the two halves of the gun.
RECEIVER COMPONENTS -- Only four parts to worry about, and they are almost all easy!
The trigger/carrier group is called Guard-complete assembly (45). I advise leaving it together as a unit. Yup, call the gunsmith if it needs more than a spray or dunk job. The screw heads are staked, if that gives you an idea of their permanency:
Removed the one screw at the rear end of the trigger guard with the aforementioned 3/16ths" hollow ground standard screwdriver.
Pull down and rearward on the Trigger Guard. A slight side-to-side wiggling may help. If jammed, soak overnight with penetrating oil. If still jammed, yup, see a gunsmith.
Cartridge cutoff (29), and bottom of Breech Bolt (31):
Shake the gun, and the cutoff should fall out. If wedged in with grime, gently press ends with fingers to rock back and forth. As a last resort pry very gently after soaking in penetrating oil overnight; it is only held in by shallow round mortise in the center. Or, back to the gunsmith if it has REALLY been neglected! :roll:
Next, lay the receiver on its left side, with the Ejection Port facing up. Remove the Ejector and ejector spring (30), by gently prying with your screwdriver:
Next, remove the Breech bolt. Memory aid: "rocker switch," shown depressed forward for shooting forward.
Depressed reward for removing bolt rearward from receiver:
The receiver is now empty.
Reinstall in the reverse order:
Hold the Receiver upside down, and slide Breech Bolt "up and in," held flush against the top of the receiver with your finger, against the Firing pin retractor (35) spring pressure
Breech bolt rocker switch depressed forward with your screwdriver. ("forward to shoot forward.") You can now take your finger off the underside of the bolt.
Lay the Receiver on its left side, ejection port facing up.
Slide in the Ejector spring in flush, using just your fingertips. Start behind the slot, and gently guide it forward; it will drop right in! If it gets stuck sideways, remove with a screwdriver and try again; it becomes easy with practice, just like everything else.
Lay the Cartridge cutoff back into its slot and round hole
Guide the Guard back in and up, careful not to knock out the cutoff, and reinstall the screw at the rear of the trigger guard.
AND FINALLY!
To reassemble the two halves, make sure the Mag pin is in the 8 o'clock position.
With the forward half of the gun turned slightly less than one quarter clockwise to the rear half, so the Barrel threads mesh with the Receiver (lack of) threads, gently slide them together, making sure the Slide is fully forward, which holds the Mag and slide bar fully forward.
Rotate the forward half counterclockwise, again assuring the slide bar is fully retracted. Align the Mag with the Receiver. Slide the Mag aft until its threads are aligned, then lock with the Mag pin by rotating the Mag from 8 o'clock to 5 o'clock. Then pushing the fin through to 11 o'clock position, which keeps the Mag from unscrewing.
The gun is now ready to shoot!
If you are just thinking about getting one, and you will be in the vicinity of St Louis, you can rent one of dozens of beautiful M12's and Super X One's here at the Winchester company-owned club:
It is located in East Alton, IL, right across the Mississippi River, and right up the road a mile from the Olin Winchester ammo plant, where all their shotshell manufacturing still takes place:
After a long delay with no free time to correct the damage Photobucketup did to my OP, I've made some time to do a complete rewrite, using imgbb.com to host the pics, hopefully forever. Everything is brand new, except the gun itself!
M12's are still plentiful and fairly inexpensive these days, with over 2 million manufactured between 1912-1963, and a few after that. Unfortunately, despite that they were pricy in their day, they too often have been left dirty, and many are rust buckets, mine included, thanks to unknown previous owners. It still shoots like a dream, though! 8)
The rust may be because taking them apart to clean them properly is an intimidating mystery to some owners, though as you will see, it shouldn't be. :?
All references are from the butt of the gun, looking forward towards the muzzle, and part numbers and names used, as this diagram shows:
MAKE SURE THE GUN IS UNLOADED, AND THE TRIGGER SAFETY ON, FIRST!
The M12 shown in the assembled and ready to fire condition:
LOCKING AND UNLOCKING THE MAGAZINE -- Separating the gun into two halves, known as "takedown."
The first step of disassembly, (and last the step of reassembly in reverse order,) is to unlock (lock) the Magazine tube (21) ("Mag" hereafter) for takedown. This can be done as often as you like, and becomes second nature with practice, just like an O/U. I keep my M12 in a takedown case, just like my O/U.
The Magazine locking pin (19) ("Mag pin") is shown in the locked, ready to fire, 11 o'clock position:
Note the Mag is fully rearward, (locked and ready to fire condition,) with the Mag pin right next to the Magazine band (14) ("Mag band").
During takedown and reassembly, you must take care for the threads on the Barrel (11) and Mag, and their mates inside the Receiver (1):
Depress the Mag pin to the 5 o'clock position, then rotate the Mag pin and Mag together (the pin is your lever) to the 8 o'clock position, one-quarter turn:
If the Mag won't turn with the leverage provided by the Mag pin and your fingers, you may have grime, rust, or damage, either under the Mag band, or in the Receiver/Mag threads.
IF AND ONLY IF it won't turn easily, first try removing the Magazine band bushing screws (12) ("Mag band screws") (shown installed above/removed below) to allow the band to be spread a little bit wider on the Mag:
The Mag band should never make immovable contact with the Mag, but it does hold the Barrel tight when the two screws are installed, by design. The Barrel is fixed, the Mag is designed to slide forward and rearward through the (snug) Mag band, only when unlocked, to disengage the receiver for takedown.
The Barrel above is shown popped out (the Mag band functioning like a "U-shaped" spring with the screws removed.) This is the normal way the Barrel is LATER STEP separated (and reinstalled ) from (to) the Mag.
Also, the "Barrel flange" is shown, which goes into the Mag band and Magazine band bushing, (13) into mortises cut into them.
As with everything on neglected guns, if something is stuck, soak overnight or longer with penetrating oil. If that doesn't free it up, see a gunsmith. Never use tools which generate excessive leverage. This gun is designed to only need a 3/16th" hollow ground standard tip screwdriver to disassemble.
Assuming the Mag slides freely, slide the Mag, Action slide (25) and Action slide handle (28) ("Slide") forward about 4" until they all contact the "Mag flange:"
The Mag flange's rear edge is the forward limit of travel for the Action slide sleeve screw cap (27).
The Slide, cap, and handle are normally left installed on the Mag. The cap requires a special tool from Brownell's, or a home made one, to remove, and there is no reason to for normal cleaning.
The Action slide (25) bar must be fully retracted from the Receiver BEFORE you attempt to remove the forward half of the gun from the rear half.
THIS WILL CAUSE DAMAGE:
THIS IS PROPER: Action Slide bar fully flush with the Receiver extension (8) BEFORE you try to separate the halves:
Hold the Buttstock (47) and Receiver still, keep forward pressure on the Slide and rotate the forward half of the gun just slightly less than one-quarter turn clockwise, then gently draw it forward and clear of the Receiver, carefully so as not to bung the threads. A good "cheat" is to hold the gun vertically, so there is no side-load on the threads.
The M12 in takedown:
Note again, the difference between when the Mag is unlocked, above, slid about 4" forward from the Mag band, compared to when it is locked:
SEPARATING THE BARREL FROM THE MAG -- It's going to start getting tricky now!
The Mag can be left internally intact or disassembled, on or off of the Barrel, your choice. The exception is if you want to remove the Mag band and Action slide handle retaining (leaf) spring (15) from the Mag. To remove those, both the Barrel/Mag separation and Mag disassembly are required, together, but we'll hold off on that, until we disassemble the Mag.
Once the forward half of the gun is free of the Receiver, set the Receiver aside.
As mentioned above in the stuck Mag band comments, remove the Mag band screws, and "pop" the Barrel apart from the Mag by inserting the fingers of both hands in the gaps between the two parts.
The Barrel and attached Receiver Extension is then set aside for normal cleaning. Leave the Extension attached to the Barrel. Removing and adjusting Barrel tension is only for a well-experienced M12 gunsmith to attempt.
Reassembly will again be the reverse:
Gently place the rear end of the Mag into the Receiver extension
Line up the Barrel flange with the reassembled and installed Mag band and Magazine plug stop (16), (see below, looks like Felix the cat)
Make sure the Mag flange (not the Barrel flange) is at the 9 o'clock position:
Squeeze the Barrel back into the Mag band, by making "fists" around the Barrel and Mag, and slowly closing them.
Finally, reinsert and tighten the Mag band screws. Some may wish to consider Blue Loctite.
This too all becomes second nature with practice, though it need not be done regularly unless the gun gets wet or you want to "deep clean" it.
DISASSEMBLY AND REASSEMBLY OF THE MAG -- Now it starts getting a little complicated! :?
The Mag pin has a small "spring-clip" set into a slot on the side of the pin. One end of the spring is rounded, the other forms a protruding "tip."
Note above, the spring inside the Mag pin has been depressed with a small standard screwdriver (the only tool required) and removed from the Mag, then partially reinserted to show the proper way it is reinstalled, later. It only works one way!
The rounded end of the spring MUST BE reinstalled on the 8 o'clock end, and the protruding "tip" towards the 2 o'clock end. Memory aid: "TIP-TWO" (like "tip-toe")
Next, reverse the Mag pin and stick it back in its hole as an easily removed "keeper," while you remove the two tiny Magazine plug screws (18) (also shown are the Mag band screws)
If you don't do it this way, if the pin is completely removed and you unscrew the plug screws, the Magazine spring (22) will shoot the Magazine plug (17) (not the Three-shell wooden plug (24)) out like a rifled slug of just about exactly the gauge your gun is!
Conversely, if you leave the Mag pin installed normally, and first remove the plug screws, you will have nowhere near enough hands to hold the gun, and the plug, and try to work the pin spring out of the mag...trust me on this!
Then the Mag plug is held by the thumb against spring pressure, the Pin easily withdrawn, set aside, and then the Spring tension is slowly released, covered with the palm of the free hand.
Remove the Mag spring and Magazine follower (23) and clean, swab with oil, and/or replace with a new spring to your heart's content.
My gun was built in 1929, and while I have no idea if this is the original spring, my gun never got a drop of love before I bought it about 5 years ago, and I haven't replaced it. Seems to work perfectly, and I shoot a fair amount of trap, skeet, 5-Stand, and Sporting Clays with it, far more than its previous lifetime total round count, judging by the lack of internal wear.
Next is removing the above-mentioned Magazine plug stop (16), "Felix the cat." It is a ring with two "ears," one for each side of the Barrel. It slides off and on the rear of the Mag plug, obviously. The trick is remembering which way it goes back on!
Finally, now you can slide off the Mag Band, its Magazine band bushing (13), and the Action slide handle retaining spring (15) (leaf-type).
That is the Mag totally disassembled if ever you want/need to do it.
Removing parts on the M12 is easy, but there are several WRONG ways to reinstall them and only one correct way!
First, back on with the Mag band, AFTER you correctly install its bushing; that means the large-side cutouts with threads showing are upwards, towards the Barrel.
Next, slip the leaf spring back under the band:
Now it's time to rebuild the Mag internals:
First, put the Mag follower on the Mag spring, and loosely insert it in the Mag.
Next, the slot in the Mag plug goes on the opposite (right) side of the mag flange. This slot and the gauge-stamped tab on the Mag plug stop ("Felix") is what limits the rotating of the Mag to one-quarter turn.
Before inserting the Mag plug in the Mag, the plug stop is slid over the rear of the plug, with the stamped gauge number on the tab facing towards the rear of the Mag (follower end) and the tab in the slot.
Then, compressing the Mag spring flush with your fingers, the Mag plug is inserted in the Mag, with the plug stop ears pointing up to receive the Barrel.
It is all temporarily held together with the reversed Mag pin again, then the plug screws are replaced and tightened. Some may wish to consider Blue Loctite?
Finally, with the plug screws tight, the Mag pin is withdrawn, and reinserted properly, FROM the 8 o'clock direction, with the "tip-two" (o'clock.) The pin spring is depressed with the screwdriver tip, and the pin inserted.
It now will not fall out (the purpose of the tip,) but it also will cycle from unlocked to locked properly; if it is installed incorrectly, it won't cycle properly, or it may fall out on the ground and could be lost.
The Mag pin is left in the 8 o'clock position until you wish to rejoin the two halves of the gun.
RECEIVER COMPONENTS -- Only four parts to worry about, and they are almost all easy!
The trigger/carrier group is called Guard-complete assembly (45). I advise leaving it together as a unit. Yup, call the gunsmith if it needs more than a spray or dunk job. The screw heads are staked, if that gives you an idea of their permanency:
Removed the one screw at the rear end of the trigger guard with the aforementioned 3/16ths" hollow ground standard screwdriver.
Pull down and rearward on the Trigger Guard. A slight side-to-side wiggling may help. If jammed, soak overnight with penetrating oil. If still jammed, yup, see a gunsmith.
Cartridge cutoff (29), and bottom of Breech Bolt (31):
Shake the gun, and the cutoff should fall out. If wedged in with grime, gently press ends with fingers to rock back and forth. As a last resort pry very gently after soaking in penetrating oil overnight; it is only held in by shallow round mortise in the center. Or, back to the gunsmith if it has REALLY been neglected! :roll:
Next, lay the receiver on its left side, with the Ejection Port facing up. Remove the Ejector and ejector spring (30), by gently prying with your screwdriver:
Next, remove the Breech bolt. Memory aid: "rocker switch," shown depressed forward for shooting forward.
Depressed reward for removing bolt rearward from receiver:
The receiver is now empty.
Reinstall in the reverse order:
Hold the Receiver upside down, and slide Breech Bolt "up and in," held flush against the top of the receiver with your finger, against the Firing pin retractor (35) spring pressure
Breech bolt rocker switch depressed forward with your screwdriver. ("forward to shoot forward.") You can now take your finger off the underside of the bolt.
Lay the Receiver on its left side, ejection port facing up.
Slide in the Ejector spring in flush, using just your fingertips. Start behind the slot, and gently guide it forward; it will drop right in! If it gets stuck sideways, remove with a screwdriver and try again; it becomes easy with practice, just like everything else.
Lay the Cartridge cutoff back into its slot and round hole
Guide the Guard back in and up, careful not to knock out the cutoff, and reinstall the screw at the rear of the trigger guard.
AND FINALLY!
To reassemble the two halves, make sure the Mag pin is in the 8 o'clock position.
With the forward half of the gun turned slightly less than one quarter clockwise to the rear half, so the Barrel threads mesh with the Receiver (lack of) threads, gently slide them together, making sure the Slide is fully forward, which holds the Mag and slide bar fully forward.
Rotate the forward half counterclockwise, again assuring the slide bar is fully retracted. Align the Mag with the Receiver. Slide the Mag aft until its threads are aligned, then lock with the Mag pin by rotating the Mag from 8 o'clock to 5 o'clock. Then pushing the fin through to 11 o'clock position, which keeps the Mag from unscrewing.
The gun is now ready to shoot!