to fit barrel.
ful not to set the clamp up too tightly on a shotgun barrel if it is a new barrel, or a barrel you are going to use again, as you may crush it. But when setting it up on a high-power rifle barrel, oil the threads on the bolts holding the two parts of the clamp together, and pull the nuts up tightly with a long-handled socket-wrench,
Removing a round barrel from bolt-action receiver, using Parmalee pipe wrench on barrel.
A shotgun barrel has a fairly straight taper from the breech, so the clamp can be fitted back close to the receiver, but on a high-power rifle it has to be fitted several inches ahead of the receiver, on the straight-tapered portion of the barrel.
Most shotgun barrels and many high-power rifle barrels, including the Springfield and Krag barrels, can usually be removed from their receivers with a Parmalee wrap-around type pipe-wrench. This wrench can be purchased from plumbing supply houses—the size that comes for girths for y2" and J4" pipe is the correct one. Two or three thicknesses of emery-cloth in the receiver in making one complete revolution in the threads. After the barrel is chucked in the lathe, bring the facing tool lightly against the end of the barrel, or against the barrel shoulder, and set the micrometer carriage stop against the forward end of the lathe carriage. Next, back off the micrometer stop the required number of thousandths of an inch for one revolution of the barrel, less the amount required to make the marks on receiver and barrel meet. It is easy to determine this amount, if the lathe has a protractor collar on the spindle, graduated in degrees. In this case, place the barrel, with the receiver screwed up on it, in the lathe chuck and bring a sharp-pointed tool in the tool rest up to either the mark on the barrel or on the receiver and take the reading from the protractor collar, then revolve the lathe spindle until the other mark is at the tool point and read the protractor again. The difference in degrees is then figured for what part of the full circle of 360 degrees it is, and this is then reduced to thousandths of an inch by dividing the number of thousandths of an inch that the barrel moves in a full revolution by this number. This number of thousandths of an inch is then deducted from the number of thousandths of an inch the barrel moves in a full revolution, and the answer is the amount the micrometer stop is to be backed away from the lathe carriage.
A thread must be machined from the rear end of the barrel, on such barrels which have a blank section at the rear machined to a diameter of the root diameter of the thread. Sometimes, a section the width of a thread must be machined to thread-bottom depth ahead of the front end of the thread, but sometimes the threads are machined out of the front end of the receiver far enough back so that this is not necessary.
If the rear end of the barrel is slotted for an extractor, this slot must be deepened. This is easily done while the barrel is still in the lathe, using an electric tool post grinder, with a grinding wheel narrow enough to enter the extractor slot. It may also be done on the milling machine or, if necessary, it can be done by hand, with files.
The foregoing method of bringing a barrel to its proper place in the receiver when it screws past the register mark can only be used if a chambering reamer for this caliber is on hand because, of course, after shortening the barrel at the breech end the chamber must be deepened the same amount.
If no chambering reamer is available and there is no rush about the job, the gun may be returned to the factory for rechambering, after the barrel has been firmly screwed up to its proper place. If, however, the gun is needed at once, instead of shortening the barrel so that it can be seated one turn deeper in the receiver, a steel shim must be placed between the barrel shoulder and the part of the receiver against which this shoulder bears, so that the barrel screws up tightly at the register mark. If shim stock of steel the proper thickness for this job can be obtained, this is the best thing to use, but if this is not obtainable in proper thickness or width, some other thin stock must be used. When using this steel shim, lubricate it either with oil or collodial graphite to prevent it tearing under the twisting pressure.
There is another method which I saw used which worked perfectly, yet I would not recommend it. A man was up at a mountain ranch with a Luger pistol, the barrel of which loosened up, and when he screwed it up tightly, it went past the register mark. There was no thin steel available there, nor anything else to use as shim stock, but the rancher had some dry, powdered litharge and glycerine with which to mix it. The man with the Luger, mixed a rather stiff paste of this, applied it to the threads of the barrel and receiver, are covered with powdered rosin on the cloth side, wrapped tightly around the barrel with the emery side out, and the wrench is then placed over this in the right direction to tighten when unscrewing the barrel. It is often necessary to add a foot or two of pipe to the wrench handle to give the power necessary to loosen the barrel. Enfield barrels cannot be unscrewed with this wrench. The clamp must be used on these latter, quite often the receiver must be heated and also must be tapped on the bottom with a hammer.
After the old barrel has been removed, clean out the threads in the receiver with an old tooth-brush, or a new one from the ten-cent store, dipped in gasolene. Also, clean the threads on the new barrel with brush and gasolene, to remove the heavy oil and any dirt that may have collected upon them. Oil the threads of the new barrel with a light oil that is acid free, and screw the barrel into the receiver as far as it will go by hand. Place the barrel in the vise or, in the case of a round barrel, in the barrel clamp, with the meeting-mark of the barrel upright, and screw the receiver up to placc with the monkey-wrench. If you cannot make the receiver screw quite up to the mark on the barrel, unscrew it from the barrel and, using a large, flat, dead-smooth file or a large carborundum stone, dress off the front of the receiver slightly and, after cleaning it, screw it onto the barrel again.
Repeat this process until you can screw the receiver up to its proper position. If, however, the receiver screws up too far on the new barrel, the proper procedure is to place the barrel in the lathe, face-off the end of the barrel and the barrel shoulder far enough so that the barrel can make another complete turn, less the amount required to make the marks on receiver and barrel meet. Knowing how many threads to the inch are on the barrel, it is easy to figure just how many thousands of an inch the barrel will move and screwed the barrel up to the mark. He heated the barrel and receiver ring slightly to hasten drying and laid the gun in the sun until the following day, when he again put it into use and had no more trouble with it. I had occasion to replace this barrel with a new one the following year, it was the tightest Luger barrel I have ever removed and I have changed a number of them.
Shotgun barrels of the take-down type have an adjustment by which they can be kept at the register marks, but sometimes a solid-frame type goes past the mark in fitting a new barrel and the steel shim may be used in this case or, as the threads are fine, the necessary amount may be filed from the end of the receiver to bring the register marks together.
Revolver barrels do not screw up to their proper places, as rifle and shotgun barrels usually do, but must be fitted. The threads on the barrel are usually oversize and must be lapped into the frame threads with fine grinding compound. The barrel may be held in hardwood blocks, grooved out to fit closely and lined with powdered rosin. These blocks are placed in the vise around the barrel and the vise is drawn up tightly, a small amount of valve-grinding compound is placed on the barrel threads and the frame is screwed onto the barrel by hand. Screw up the barrel as tightly as possible without jamming it, then reverse it a revolution or two and then screw it up again a little farther than before. Work it back and forth in this way a few times, then remove the frame from the barrel and add a little more grinding compound, repeating this procedure until the barrel shoulder is screwed up tightly against the face of the frame. Unscrew it again and wash out all grinding compound, then oil the threads with light, acid-free oil and screw the frame onto the barrel, this time using a hammer handle, or other piece of hardwood, through the cylin der opening in the frame to screw it up tightly but be careful not to spring the frame.
If you happen to be a fool for luck, the barrel may be in the right place, or so close to it that it can be forced there, but as most of us are honest men it will probably be as far from the proper place as possible. In this case, measure the distance from the rear face of the frame to the rear end of the barrel, then remove the barrel from the frame, after estimating as closely as possible what part of a full revolution the barrel must
Revolver barrel clamped in grooved wood blocks in vise jaws, in order to unscrew frame from barrel.
Revolver barrel clamped in grooved wood blocks in vise jaws, in order to unscrew frame from barrel.
take to bring it to its proper position in the frame. Count the barrel threads and figure how many thousandths of an inch the barrel will move back when screwcd to its proper position, and deduct this amount from the measurement you made of the distance from the rear face of the frame to the rear end of the barrel.
Place the cylinder in the frame and measure the distance the front end of the cylinder is from the rear face of the frame, and deduct from this the distance from the rear face of the frame to the end of the barrel when the barrel will be in its proper place in the frame. Add to this .0025" for clearance and cut this amount from the rear end of the barrel, in the lathe. Cut the barrel shoulder back the required number of thousandths of an inch to allow the barrel to screw up to place, and remove any burr from the rear end of the barrel with a round, tapered oil-stone or fine carborundum stone. Now, screw the frame onto the barrel again, and if your measurements are correct, the barrel will come to the proper place in the frame and have the correct clearance at the front end of the cylinder. If the barrel does not quite come to place, a small amount may be removed from the front face of the frame, where the barrel shoulder bears. Check the clearance of barrel from cylinder with a thickness gauge, checking each chamber, because now and then a high spot shows up on a cylinder and this must be dressed off.
Sometimes it is desired to fit a factory barrel to some action other than the one for which it was designed. When the threaded end of the barrel is larger than the threaded opening in the receiver to which it is to be fitted, it is necessary to place the barrel in a lathe and turn down the breech end to the proper diameter and length to fit the receiver, and then thread it with the same thread as the receiver.
Some actions use the regular U. S. form of vee-thread, while others, such as the Springfield, Krag and Enfield, use the square form of thread. In this square form of thread, the thread-cutting tool must be the same width at the front edge as the groove in the receiver thread, and the thread tool, when viewed from the front, must incline to the right for a right-hand thread and to the left for a left-hand thread, at the same angle as the lead of the thread, so that the thread tool will clear the sides of the thread below the cutting point of the tool. The nose of the thread tool must also have clearance ground on the sides from top to bottom, leaving the top edge the widest part. The cutting edge of the tool must be straight and parallel to the axis of the lathe, and the top of the cutting tool should slope back or down from the cutting edge.
Cuts should be very light at each pass of the tool and the cutting edge should be just slightly above the center line of the lathe. The cutting edge of the thread tool should be oil-stoned until it is very smooth and sharp, and should be examined after each pass to see that the corners are not dulled.
In fitting a square thread, .001" clearance should be left at both top and bottom of the thread. This is done by machining the blank to be threaded .002" smaller in diameter than the bottom of the threads in the receiver, and cutting the groove of the thread on the barrel .001" deeper than the depth of the receiver thread.
The lathe should be thrown out of gear before the thread tool reaches the end of the cut (but do not release the half-nuts of the lathe carriage from the lead screw to do this) and the lathe is then turned by hand until the tool reaches the end of the cut. This is necessary because of the broad edge of the cutting tool, for it is not possible otherwise to stop the tool right at the end of the cut and the shock at the end of the tool, if it is not stopped at the end of the cut, may cause it to dig in and displace either the tool position or the work. This is not necessary in cutting a vee-type thread, as this is a shear type of cut and the low speed at which the lathe is driven while thread cutting will enable the vee-type cutter to continue to cut without being displaced or displacing the work if you miss the stopping point by a degree or two.
In cutting left-hand threads, the cutter is started in the work at the shoulder end and, before beginning the threading operation, a groove the full depth of the thread to be cut should be cut at this point for either the square or the vee form of thread, so that the threading tool can be placed in this groove each time to start cut.
In fitting rifle barrels to actions other than those for which they are designed, it will be necessary to cut out the original extractor groove in the end of the barrel, if it has one, unless the position of the extractor groove for the action to which you are fitting the barrel comes at the right place. As cutting off enough of the barrel to remove the extractor groove usually means shortening the chamber, a chambering reamer must then be used to lengthen it enough to give proper seating depth to the cartridge.
If the barrel to be fitted is smaller than the receiver to which you wish it to fit, the receiver may be bushed or, more properly, the barrel at the breech end may be built up large enough to thread for the receiver. This may be done by turning down the threaded end of the barrel to remove the threads upon it and to bring it to some standard fractional-inch size for which you have a die. Carry this size down the barrel farther than the distance the barrel is to screw into the receiver to which you are fitting it, so that a new shoulder may be made on the piece of steel that you screw onto the barrel to enlarge it.
After threading the barrel with a die, drill and tap a piece of steel to screw onto it that will be large enough to thread for the receiver and to leave a substantial shoulder at the end of the thread. Clean the die-cut threads on the barrel with gasoline, to remove all oil from them and do the same with the tapped threads in the piece of steel, then tin both of these threads with solder and screw the steel piece onto the barrel as tightly as possible, keeping both parts hot so that the solder remains soft. After the barrel is cool and the solder well set, a new end is machined on it the proper size to thread for the receiver, and the front end of the steel piece fitted to the barrel is brought down in a taper to barrel contour at that point
Barrel blanks are fitted to actions in the same manner as has been described for fitting factory barrels to actions other than those for which they were designed. In chucking either a blank or a barrel for threading to fit an action, the blank or barrel is centered by the bore or chamber and not by the outside of the blank, as the bore may be slightly off-center. This can usually be done closely enough by eye or, if you wish, the dial
Hardened steel plugs or mandrels, ground on ccntcrs, to insert in muzzle and chamber of rifle barrel when it is to be machined on ccntcrs in a lathe.
Hardened steel plugs or mandrels, ground on ccntcrs, to insert in muzzle and chamber of rifle barrel when it is to be machined on ccntcrs in a lathe.
gauge may be used to check the centering of the bore. When the blank is machined on centers and threaded, the bore is, of course, centered by the lathe centers, and the breech end may be faced off square with the thread if it is out of true, by using a narrow facing tool ground to an angle to go between the end of the barrel and the slope of the center point. A special tail stock center is sometimes used for this job that has had part of one side ground away for a distance back from the point, either flat or in a groove, so that the point of the facing tool will go to the bore or chamber opening. This is not neccssary however, as with a regular center in place the barrel end may be faced from the outside toward the center and when the point of the facing tool touches the lathe center, the center may be very slightly withdrawn, the barrel will raise slightly on the point of the
tool and the small remaining fin will be cut off smoothly. Leave the facing tool in position after this occurs and stop the lathe before withdrawing the tool.
In fitting barrels to actions in which the end of the barrel comes against the face of the breech-block, as it usually does for rimmed cartridges, a Starrett micrometer head with lock-nut can be used as a micrometer depth-gauge by fitting the head into a steel block that will reach across the front end of the receiver ring, The
hole through the block for the micrometer head must be at right-angles to the face of the block and the lock-nut must be recessed so that it is below the surface of the block, yet holds the head in place in the block without tightening on the spindle.
Some actions for rimless cartridges have a rear shoulder in the receiver for the rear of the barrel to bear against, such as the Mauser has, and in this case the distance between the rear shoulder and the front edge of the receiver ring is measured in the same way as described for rimmed eases.
Other actions for rimless cartridges, such as the Springfield, have no rear shoulder, and the length of the portion of the barrel extending back into the action is measured on an old barrel or may be taken from the front end of the receiver to the face of the bolt, while the bolt is locked in place.
Some barrels, notably the .22 long-rifle, are very touchy concerning the contact between the barrel shoulder and the receiver, and have to be spotted-in to get a perfect contact. The front of the receiver is
lightly coated with prussian-blue and the barrel is then screwed up tightly against it, then when the barrel is removed from the action the high spots on the barrel shoulder are coated with the blue. These high spots are then carefully worked down with a very fine file of the Swiss pattern and the barrel tried in the receiver again, the performance being repeated until the contact between barrel shoulder and receiver is perfect.
The recess in the breech end of the barrel for rimmed cartridges controls the head spacing of the cartridge. This may either be cut with a facing-type cutter, with a pilot in the barrel or, if the barrel is held in a chuck in the lathe spindle, it may be cut with a lathe tool at the time the rear end of the barrel is faced off.
In case the thickness of the standard rim for the cartridge in question is not known and there is no gauge available, measure the rim thickness of a number of cartridges with a micrometer and, taking an average of these, cut the recess to that depth for the rim of the cartridge. The micrometer carriage stop should be used on the lathe for this operation, so that it may be done to the correct number of thousandths of an inch.
Barrels or barrel blanks may be cut down to a smaller diameter in the lathe, if care is used. Ordinary sporting-weight barrels should not be turned down to a smaller diameter, as these are properly designed by the factory or the arsenal to be as light as possible. If it is desired to smooth up the outside of them, this can be done in the lathe, with the barrel on centers, either by filing or with an electric tool post grinder. Center plugs should be made for both the breech and the muzzle, of tool-steel, hardened and then ground on centers. The tailstock may be offset so that the tool post grinder may be used to make a cut the full length of the taper of the barrel, but it is better to leave the centers in their true center position and use a lathe with a taper attachment, resetting it each time the grinder travels the length allowed by the taper attachment.
In turning down barrel blanks or heavy barrels the back rest cannot be used to support the barrel, due to the taper of the work, therefore, as the barrel must be supported to keep it from vibrating under the cut, a
Principle of detecting crooked barrels. Left view shows shadow cast by a straight barrel—other two show shadows cast by crooked barrels.
short straight portion is turned upon the barrel and the steady rest is set up at this point to support it. It may be necessary to make two or three different positions to set this steady rest along the length of the barrel and after each short portion between the tail stock and the steady rest is finished, the rest is moved to another
Facing back a barrel shoulder in the lathe. using micrometer carriage stop. This micromcter carriage stop, which you see fastened to the lathe bed, measures tiie travel of the lathe tool carriage along ihc bed, in thousandths of an inch, so that the shoulder of the barrel is cut back the exact distance necessary to allow the barrel to screw up to its proper placc in the receiver.
position along the barrel and another portion of the barrel is finished. The barrel is equipped with center plugs and the lathe centers are left in the true center position and a lathe equipped with a taper attachment is used to machine the barrel. Light cuts must be taken, so as not to spring the barrel, and the centers must be carefully watched to see that the barrel does not heat from the turning operation and become tight enough between centers to spring it. After machining the bar-
The modern» overhead press for straightening rifle barrels.
rei it should be checked for straightness, as the removal of very much metal from its outer surface may release strains in the barrel that will cause it to spring out of true. A wire is stretched across a window and the barrel is pointed toward it and held in a rest so that is may be revolved while watching the shadow cast by the wire in the bore. If the shadow is a true line, the barrel is straight but if there are breaks in it and part of the line of the shadow is to one side of the balance of it, the barrel is crooked.
Some barrel makers claim the barrel should not be straightened, as when it becomes heated later, in firing, it may come back to its crooked position. Others claim it should be straightened. This straightening process is now almost entirely done in an overhead press, while the barrel is pointed toward the window with the wire stretched across it and the shadow in the bore that is cast by the wire is watched during the straightening. This overhead press has two stationary fingers several inches apart and between these a third finger with screw adjustment comes against the barrel from the opposite side. The crooked portion of the barrel is placed between the two stationary points, or fingers, and the barrel is turned until the outsprung portion of the crooked part of the barrel is against the movable finger. This movable finger is then used to spring the barrel back to a straight position. As the barrel has some spring in it, it must be sprung past center, so that when it springs back it will be straight.
Old method, using lead blocks and lead hammer to straighten rifle barrels.
The other method of straightening a barrel is to lay it upon two lead blocks, having the crooked portion between the blocks with the crook upward, and it is then struck with a lead hammer to straighten it. This requires considerable more skill than the press method. Skill is also required to properly locate the crooked portion of the barrel to know where to straighten it.
In filing barrels upon the outside to get a smooth finish, a twelve or fourteen inch file of an inch or more
in width should be used. This file should be either of the second cut or about a #2 cut in the Swiss pattern pillar-type file. The lathe should turn in the next to the lowest speed on open belt. To prevent the file picking up cuttings of the barrel between its teeth (known as
Striking or draw-filing a barrel to remove circular tool marks.
pinning) and scratching the surface of the barrel, the file should be chalked with common chalk. Clean the file often and rechalk it.
Striking a barrel, before polishing it, is done by holding a flat file in both hands, one at either end, across the barrel at a right-angle to the axis of the barrel, then moving it back and forth lengthwise of the barrel. This is often done to remove the circular tool marks on the barrel. The barrel is given its final polishing, before being buffed, with carborundum cloth while the barrel is turning at high-speed in the lathe. This removes all file marks.
Buffing a barrel for final finish may be done on a muslin buff, an inch or more thick, by applying emery paste in brick form to the buff, which will more or less impregnate the surface of the buff with the emery or carborundum in the brick. If you desire a wider range of grain size of carborundum than can ordinarly be obtained in these emery bricks, the buffing wheel may be coated with the stick-type belt dressing by holding the end of a stick of it against the buff while it is revolving and carborundum grains of any size you desire may then be rubbed into the surface of the buff, the belt dressing causing a large part of it to stick.
Another type of buffing wheel is made of thin pieces of chrome-tanned leather, enough pieces being used to make a wheel an inch or more thick. These pieces of
Muslin and leather buffing wheels and their use in buffing gun barrels.
leather are fastened together, either by sewing or with rivets, to within about one-half inch of the outer diameter of the wheel. This leaves the wheel with a yielding face, which will follow the barrel contour better than a solid face would do. The face, or properly the
Front sight band attached by a cross pin with half its diameter in the top of the barrel. Rear sight, dovetailed barrel band, attached with set screw underneath.
edge of the wheel, is coated with glue and while this glue is still soft the wheel is rolled on carborundum powder spread evenly on a paper laid on a flat surface so that the wheel takes an even coating of the carborundum grains. Usually carborundum grains of #120 to FFF size are used on either type of buff. Buffs should be eight inches in diameter and turn at a speed of at least 1750 R.P.M.
Cuts for sights in barrels, especially barrels of sporting weight, should be avoided as they cause uneven vibrations of the barrel, which causes inaccuracy.
Various methods of attaching forearm and rear sight bands to rifle barrel with screws.
Sights mounted on the barrel should be mounted on barrel bands. These barrel bands can be held in place on the barrel with light cross pins, as are the sights of the Springfield service rifle; or the rear sight band, if an open rear sight is desired, may be held in place by leaving a heavy portion on the bottom of the band inside the forearm and running a headless set-screw, tapped into this heavy portion, through the band and into a slight depression in the bottom of the barrel, made by the point of a drill. If, due to the construction of the rifle there is not room to leave a heavy portion on the bottom of this rear barrel band, a set-screw may be run in flush on the top in the bottom of the dovetail slot for the open sight, although this is not as .good practice as putting it through the lower side of the band as it tends to lift the upper part of the band away from the barrel.
Forearms of single-shot rifles may be held to the barrel with a band and screws running through the forearm, through the heav}' portion of the bottom of the band and into a depression made in the bottom of the barrel with a drill point. These forearms may also be held to the barrel with a screw tapped directly into the barrel, in which case the screw should be carefully cut
for length so that it bottoms in the hole in the barrel, thus filling the hole completely, which will help prevent uneven vibrations of the barrel.
In cutting off the muzzle end of barrels, they may be sawed off with a hack-saw and then finished up true in the lathe, or they ma}' be cut off in the lathe. After the cutting-off operation, the muzzle may be shaped up with a lathe tool, but if the inner or bore part of the muzzle is shaped up with a lathe tool be sure that the bore runs dead true or opposite sides will be of uneven length. The muzzle may also be finished, or crowned, by a crowning tool having a pilot that enters the bore and rides on top of the lands. The cutter is made of flat tool-steel, shaped to produce the crown on both the inside and outside of the muzzle at one operation. This cutter passes through a slot in the shank of the pilot and is held in place with two flush pins. The edge is relieved on opposite sides from the cutting edge. It may be operated by hand, in a drill chuck in the lathe, or in a drill press. It is turned slowly and should be kept lubricated with cutting oil.
Barrel Thread Sizes of Various Rifle Actions
Name of Action Diameter Per Inch Type
Single Shot Action 821' 16 Vee
Winchester #3 Heavy
Single Shot Action 935' 16 Vee
Ballard Single Shot 950' 18 Vee
Single Shot Ilammerless 945' 16 Vee
Stevens Ideal #44
Single Shot Action 8125' 20 Vee
Stevens Ideal #44 K"
Single Shot Action 875' 16 Vee
Remington Single Shot
Navy Action, Pistol 850 12 Square
American Krag Action 980" 10 Square
Norwegian Krag Action 1.056' 12 L.H. Square
Springfield Action 1,040' 10 Square
Enfield Action (Model 1917) 1.118' 10 Square
Mauser Model'98 Action 1.100' 12 Vee
Winchester Model 54 Action 1' 16 Vee
Was this article helpful?
There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.