Barrel Sleeving A New Way

Barrel sleeving is performed for different reasons. The leading reason is the cost saved in converting a lighter weight barrel to a quality target weight barrel. Accuracy potential is thereby improved. As a rifle is fired the barrel undergoes a series of vibrations which can have an untoward effect on accuracy. The resultant shock waves cause a barrel to oscillate causing bullets to deviate from the group. Lighter barrels tend to vibrate more.

Adding stiffness to the barrel has a tendency to change the moment about a barrel’s axis point, with a reduction of vibration or harmonics. This has been precisely proven by mounting an accelerometer at the barrel muzzle. Another reason for sleeving barrels is improved heat dissipation. An improvement in heat distribution and dissipation appears to be present in those barrels I have sleeved.

However, the leading advantage of sleeving a barrel has been conclusively borne out, in those I have sleeved, as improved accuracy in all cases. Barrel Sleeving Materials Barrel sleeving is a gunsmithing procedure involving machining and application of special sleeve/barrel bonding material. The steel material used for this method of barrel sleeving can vary in diameter as well as tube wall thickness. This will be determined by the size of the barrel being sleeved and the overall finished barrel outside diameter.

All barrels I have sleeved were standard weight or lightweight barrels 22 to 24 inches in length. Barrels had finished outside diameter at just under an inch without taper. Sleeve wall thickness can vary as determined by availability of steel pipe or tubing and is easily controlled by lathe turning. The material I chose to bond the sleeve to the barrel is J-B Industro Weld, chosen for its extremely high steel-like strength and adhesive bonding qualities, as well as viscosity controllability in its application.

The material has an impressive tensile strength of 3,960 PSI, shear strength of 15, compression resistance to 10,733 PSI and temperature tolerance to 600 degrees F. Barrel Sleeving Work In this treatise I will describe my most recent barrel sleeving project on a 24 inch standard weight Model 700 Remington barrel in caliber .300 WSM. As a sleeve, I started with a 1.050 inch diameter seamless steel pipe with 0.115 inch wall thickness and 0.820 inch inside diameter.

The pipe was later turned to 0.990 inch finished diameter, quite similar to a Remington Model 40X barrel. The original barrel weighed 2 pounds 13 ounces, resulting in a sleeved barrel weight of 4 pounds 8 ounces, closely matching a heavy target barrel of same length. In fitting the sleeve to the barrel, it must be measured and marked where

From top, one of the two Model 40X Remington actions used to test the Model 700 standard weight 7mm Magnum barrel prepared for sleeve, barrel sleeve and muzzle centering disk. the juncture of the barrel and sleeve diameters coincide. At this point the two parts will join evenly to eliminate a jog. The barrel shank is then turned so the sleeve will fit over the turned surface where barrel and sleeve diameters come together.

However, to avoid turning an excessive amount off the barrel I bored the sleeve out to a wall thickness of 0.070 inch to match the turned barrel surface. The sleeve is tried for fit over the newly turned surface until it slips freely over the barrel shank, allowing for bonding material between surfaces. The overall barrel is roughened for better metal-to-metal adhesion.

Barrel/Muzzle Centering Disk Having fitted the barrel at the breech end, it can be cut to length in preparation for making the barrel muzzle centering disk. The barrel is cut about an eighth of an inch short of the sleeve mouth, leaving a space for the recessed disk to center it. While it serves as a barrel muzzle centering disk, the sides of the disk interface the space between the inner sides of the sleeve and the outer diameter of the barrel. Be sure to leave some space all around for the J-B bonding material.

This is also the best time to polish the front surfaces of the disk. Bonding Sleeve And Barrel Prior to the bonding process, filler holes are drilled along the bottom Shown in the center is the special recessed muzzle centering disk used to precisely align the barrel and sleeve together. A series of filler holes and a syringe were used to administer the liquid material while totally preventing any voids or stresses within the system. of the sleeve.

These 1/4 inch holes are spaced about 2.5 inches apart beginning about six inches forward of the barrel/sleeve joint. A plastic two-ounce (60 cc) syringe with a 1/4 inch tip is used to inject the bonding material into the sleeve. Be sure to place a muzzle seal in the bore before working with bonding material. Applying the bonding material is uncomplicated following these

directions. Mix up about four ounces of J-B Industro Weld in a small vessel that you can pour from and that can be warmed. I used a cutdown aluminum soda can. As the J-B bonding material is being mixed, keep it quite warm so that it can actually be poured. Working time of this liquid material is about 25 minutes, somewhat less at warmer temperatures. Coat the turned area of the barrel and about six inches of the bottom of the sleeve and slip the coated parts carefully together.

Be sure the holes are at the bottom of the barrel, which must be pre-determined. At this point I place the chamber vertically in a padded vise with the muzzle up, then temporarily place the muzzle centering disk in position so the barrel will be perfectly centered. Fill the two-ounce syringe about half full and, from the bottom hole upwards, force bonding material into each hole until it oozes from the hole above it. Remove the syringe tip and place tape over each filled hole as you work your way upward.

Re-fill the syringe as needed until barrel sleeve is full. Remove the barrel centering disk, coat the contact sides of the disk and inside the remaining sleeve with bonding material, and press disk firmly into position. Thoroughly clean all excess bonding material from around the barrel centering disk and muzzle crown. Take a deep breath and step back to admire your work. Keep the barrel upright and warm for at least 24 hours. I don’t shoot a sleeved barrels for at least 48 hours.

Barrel is at perfect center with centering disks also serving as a protective muzzle crown. From left, .300 WSM and 7mm Rem. Mag. bores. 300 WSM target barrel made from a standard weight Model 700 Remington barrel. The barrel closely resembles and equals performance of a barrel costing more than $500. Conclusions Converting a good quality, standard-weight barrel into a target or varmint barrel is likely to improve rifle accuracy and will save money in the process. Always select as good a barrel as you can find.

The sleeving process, outlined herein, has improved accuracy in each of the four standard weight barrels I have converted. Two of these barrels easily parallel the performance of premium target barrels that would have cost upwards of $500 to install for much less. AG