Gun Reports - Special Reports
How To Work The Browning Auto-5
October 3, 2011
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Shortly after 1900, John Moses Browning took his idea for an autoloading shotgun to the U.S. Patent Office after parting ways with the Winchester Gun Co. The relationship ended when Winchester president T.G. Bennett wanted nothing to do with an automatic.
Gathering his prototypes from the drafting room, Browning left Winchester to make an appointment to see Marcellus Hartley, president of Remington Arms Co. Over the phone, he received an enthusiastic response, so a meeting was set up to show Remington his wares. Sitting in Hartleys office, Browning was told that the president of Remington Arms Co. had died of a heart attack that very morning. Lacking any potential American manufacturers with the means to produce his newly created semiautomatic shotgun, Browning began the search elsewhere.
The famous firearms manufacturer, Fabrique Nationale dArmes de Guerre, located at Herstal, Liege, Belgium, was waiting with open arms. By the end of 1961 alone, F.N. had produced 1,377,785 of the Model A-5 shotguns. Remington Arms produced approximately 300,000 of its Model 11, and Savage Arms produced thousands of the Model 720, with very little variance from the original design, under license from the F.N. factory. These shotguns are but three of Brownings legacies, and because of the numbers that were produced, you may run across them in your gunsmithing adventures.
Well be dealing primarily with the Browning Auto-5 here, but all the procedures for disassembly and parts replacement apply to the Remington Model 11 and the Savage Model 720.
When working on the Auto-5 or any other firearm, the rules of common sense and safety should always be followed. Be sure the firearm is unloaded and the magazine tube empty. Find out about the problems with the firearm. The more information you have the better off you are.
Complete disassembly of these firearms is a prerequisite to thorough cleaning and, of course, blueing.
The first thing youll want to do with the A-5 is pull the bolt handle all the way back so that the action locks back, bolt open. Unscrew the magazine end cap at the fore-end tip. If the magazine cap has been powered on, wrap an old piece of leather belt around the magazine cap and use vise grips to loosen it. The forearm wood slides forward coming off with the barrel, recoil spring and friction rings.
With the shotgun in a vise with protected jaws, trigger guard up, remove the lock screw for the stock screw at the rear of the bottom tang, then remove the stock screw. If the stock is a little stubborn, a few whacks with a rubber-faced dead blow hammer at the rear face of the receiver may convince it to release. Once the stock is removed, depress the carrier latch button while holding the bolt handle with your off hand and ease the bolt forward. Try not to let the bolt go flying forward because that might damage the front of the ejection port.
Returning the gun to the vise, remove the trigger plate lock screws, then the front and rear trigger plate screws on the left side of the receiver. On the Remington and the Savage models, the front trigger-plate screws are actually pins, but they do have lock screws. These pins can be drifted out once the lock screws are removed. The whole trigger group can now be removed. On the older model A-5 Brownings (before 1958), the Remington Model 11 and the Savage Model 720, the carrier spring is mounted on a stud on the receiver wall. With the newer A-5s, the carrier spring is integral to the trigger plate assembly.
The rear end of the receiver tang holds the action spring tube containing the action spring plug, action spring, and the action spring follower. To relieve tension on the spring, drift out the cross pin with a 3/32-inch punch. Pushing the pin with one hand, hold some tension on the action-spring plug with your other hand so the plug, spring and follower dont go flying out a window. A .45-caliber bore brush dipped in solvent will scrub the crud buildup inside the action spring tube quite nicely.
On the Savage 720, the end of the action spring tube is threaded into the rear of the receiver tang. There are two flats on the end of this tube
The carrier assembly consists of six parts, and normally, disassembly is not necessary. The carrier assembly has a screw and lock screw on the right and left side of the receiver. These carrier screws should be identified as to which side they came out of. If they are switched at reassembly, the lock screws will probably not line up properly. All of the older Brownings were marked on the tip of the right screw going into the receiver for replacement identification. If you are blueing and the screws are not marked, it will save some time to do so for reassembly.
Removing the bolt assembly is the next step. For this step in takedown, I suggest placing the magazine tube in the protected jaws of your vise with the right side of the receiver facing up. Close the vise with enough pressure to hold the magazine tube firmly, but dont overtighten.
Use the breech block link to slide the bolt in the receiver so the locking block latch pin lines up with the half hole along the bottom edge of the ejection port. While keeping the latch pin aligned with the half hole, take a 3/32-inch punch and drive out the latch pin from the left side of the receiver. When the punch is withdrawn, the locking block latch and spring on the bottom of the bolt will be free. Watching for it to pop up and out, remove both at this time.
While pulling rearward on the bolt handle, use the link to push the bolt forward to remove the bolt handle. The bolt assembly will now come out the front of the receiver. Unless you are blueing the metal, the magazine cutoff, along with its spring, can be left in place at the left front of the receiver. If the magazine tube is damaged and being replaced, the magazine cutoff screw will have to be backed off to remove the magazine tube.
To remove the cartridge stop, place the receiver in your padded vise with the bottom facing up. The older Brownings, the Remington Model 11 and the Savage 720 all have a slotted-head pin threaded from the top of the slot down about 1/8 inch, which holds the cartridge stop in place. Newer Brownings use a roll pin. If you find a roll pin holding the cartridge stop in place, a 3/32-inch punch will drive the pin down into the receiver for removal. There are two variations in the cartridge stops. Those made for the Remington Model 11 from 1905 until 1931 use a different style than those used after 1931, so watch for the difference if replacing one of these.
The carrier latch assembly is removed much the same as the cartridge stop. Check to see if it has a slotted head screw or a roll pin, and disassemble in the same manner as the cartridge stop.
When removing the magazine spring retainer, the Menck corkscrew tool helps contain the spring inside the magazine tube. When released of tension, this spring seems to go on longer than one of my old uncles jokes.
The trigger assembly can normally be cleaned and oiled without disassembly. If it must be taken down completely, place the hammer in the cocked position with the safety on. With a small-bladed screwdriver, get underneath the safety sear and depress the follower and spring so the safety sear can be pushed forward off its pin. Watch for the follower and spring to come quickly out of its hole. If you were able to contain them, remove the follower and safety spring.
Place the safety in the fire position. With your left hand, hold the hammer to keep it from coming forward and pull the trigger at the same time easing the hammer forward with your left hand. With a 1/8-inch punch, drive out the hammer pin and remove the hammer. The mainspring screw can now be removed at the trigger guard tang. Newer models have a small crosspin that goes through the tang and above the trigger spring. An 0.060-inch-diameter punch will handle removal of the crosspin.
When removing the trigger spring, the safety ball can easily be lost, so watch for the little ball to try and get
Drive out the trigger pin with a 3/32-inch punch, remove the trigger and then the safety. Check the safety for burrs and reinsert it into its hole in the trigger plate, making sure it slides back and forth freely. If it sticks in either direction look for high shiny spots on the safety and polish these spots smooth. With the safety in its hole in the trigger plate, put the trigger and trigger pin back in place and make sure the trigger pivots smoothly on the pin.
With tweezers or small needle-nose pliers, install the safety ball into the socket for it. To install the trigger spring, depress the spring with a punch and then install the crosspin. On the older models, the trigger spring slides in the grooves in the trigger plate tang forward until the screw hole in the rear aligns with the hole in the lower tang. Check the feel of the safety movement. If it moves too freely, the center leg on the trigger spring will need to be bent downward to increase the pressure on the safety ball. If the safety moves excessively hard, the center leg on the trigger spring will have to be bent up a bit. Replace the mainspring and the screw for it. Place the hammer and hammer pin in place in the trigger housing. Check to see that the hammer pivots freely on the hammer pin. With the hammer in the cocked position, install the safety sear, spring and plunger. Make sure the lower end of the safety sear has rotated into the proper position.
If the trigger cant be pulled after assembly, it is possible that the top part of the safety sear that strikes the inside of the link is too short or that the link may be bent. If this is the case, replace the safety sear and reshape or replace the link. With the hammer cocked, disengage the safety sear with your thumb. Push the safety to the ON position. Pulling the trigger as hard as possible, the hammer should not fall. If the hammer falls, the safety is worn or the rear of the trigger that should contact the safety is short. In either case, replace the safety or the trigger.
Upon inspection of the carrier assembly, look to see that the two legs which extend to the rear have not become misaligned. Place a steel straight edge along the outside of the carrier legs to see if they are parallel with the lifting portion of the carrier. If they are out of alignment, place the front of the carrier in a vise and with a brass hammer tap them into shape. The carrier screw holes should be in perfect alignment. To check these holes, an 0.185-inch pin or the shank end of a No. 13 drill should slide freely back and forth through both without any binding. If the holes are misaligned, one of the carrier legs will have to be bent so they are once again in line.
To disassemble the breech block, drive out the firing-pin stop pin from left to right with a 1/8-inch punch. The firing pin can now be removed. Check to see that the spring is straight, not broken or starting to crystallize. If it looks doubtful, replace it. Rotate the locking block and link forward and out of the breech block. Unless the link is badly damaged, there is no need to disassemble it from the locking block. If the link is replaced, the link pin must be staked in place to prevent side movement that could jam and damage the action.
To remove the right or left extractors, drive either of the retaining pins from the bottom of the breech block to the top with a 3/32-inch punch. There is an old and a new style extractor.
This gap should be about 0.015 to 0.030 inch. If the gap is wider than 0.030 inch, the extractor may drop the cartridge or fail with extraction. To correct this condition, tap the hook of the left extractor inward. Insert the dummy round and again tilt down, but without exerting pressure to the left extractor. If it does not release, the hook on the left extractor is too sharp or is bent too far inward and is creating excessive hook. If the hook feels too sharp, use a fine file or a hard Arkansas stone to remove the sharp edge.
If the left extractor does not move outward by pressure applied to the hook end, check the extractor spring to see if it is jammed between the extractor and the bolt body in the extractor spring hole. With coiling pliers, turn the last coil on each end of the spring in so the ends of the spring will not bind in the spring hole.
Check the firing pin for straightness and the tip for roundness and burrs. If all is well, install the firing pin and spring, the firing-pin stop pin going in from right to left. Make sure the rounded, polished end of the firing pin stop pin is situated toward the right side of the breech block.
Inspect the disassembled receiver for cracks, burrs and or other abnormalities. Flush the receiver out with cleaning solvent and if you have compressed air, blow the receiver dry. If you notice an imprint in the rear of the breech block, the action spring has become weak and should be replaced. This could also be caused by the improper setting of the recoil mechanism. If the owner doesnt have a copy of the proper settings of the friction rings for the loads being used, get him a copy of one.
If the action-spring tube is cracked or broken, replace it. If it has been bent and then straightened, the tube should be reamed with a 0.413-inch (letter Z) reamer so that the spring has no problem with drag. Check the inside top surface of the receiver for rub marks, shiny spots where the blueing has worn off. If noticeable lines exist, the link should be replaced.
The carrier latch can be checked with a straight edge along the side that faces the inside of the receiver. Make sure the carrier latch tipthe part that actually contacts the cartridge face rimhas the right angle. There should be a 1/16-inch gap at the hump on the carrier latch. The rear end of the carrier latch should always be left as it comes from the factory. In the event of extreme wear and rounding of the rear edges of the carrier latch, a very slight amount of metal can be removed to square it up.
But a word of caution here, excessive clearance between the carrier and the carrier latch will result in feed problems.
Stock and Forearm Repairs
Inspect the tang screw hole in the stock to see if it has become elliptical from recoil battering. If the hole has become excessively elongated, there is no other recourse than drilling it out with a 3/8-inch bit, plugging with a hardwood dowel, and drilling a new tang screw hole.
You see quite a few of these shotguns with cracked forearm wood. If the crack is not excessively oil soaked, it can be epoxied and clamped for repair. Ive noticed A-5 stocks and forearms usually do not have any finish applied inside the forearm or in the cavity beneath the buttplate. This will usually cause the wood to absorb moisture, swell and crack. If this is the case, advise the owner of the potential. ★