“Rifling with a single-point cutter is slow and costly but imposes little stress on the blank,” John Krieger explained. Cylinder stop - A device to stop cylinder rotation in proper alignment with the barrel of a revolver. Some people don't like the looks because it is impossible to get the square corners on the lands and grooves. 3crows said: No, Remington built Marlin . Rifling consists of spiral grooves cut into the inside of a barrel of a gun. 1. 45 to . Read more about our single-point cut-rifling here. Marlin started using Microgroove rifling in the early 50's and before that they used Ballard rifling. 0001" per pass. For. Texas. There are four ways to produce the grooves: Cut rifling. Barrels: Cut Rifling vs. Other common methods include cut rifling, hammer forging, and broach rifling. To make a rifled barrel, normally a hole is deep-drilled in a steel bar. The lands of polygonal rifling look like bulges rising from the bore. Cut rifling is more precise and makes a difference for those. and later a "hook cutter"). . We start with 4150 chrome-moly or 416R stainless steel double stress relieved bar stock, bore with the renowned Barnes gun drill, ream with an industry-standard Pratt & Whitney reamer, and then hand lap each barrel to our high-precision standards. Rifling Twist:. With a gain twist barrel the bullet cannot go to sleep. These days, specialized equipment is used to insert a cutter in the drilled-and-reamed bore of the billet in order to cut and remove a small amount of steel with each pass of the cutter. I don’t have a more accurate date for Kollner. The cutter makes a full length pass in the direction the bullet travels and the machine indexes to the next point to cut the next groove. The cutter is adjusted to cut one- to two-thousandths of an inch of metal on each pass. Also from just some recent testing by a bullet maker/ammo maker a few months ago is they do believe that they found that the 5R rifling helps the flight of the bullet in the transonic range vs a 4 groove barrel that was also being tested the bullet had a disturbance in the. Button rifling is simpler and faster than cut rifling and usually less expensive. For a pistol, broach or button does an equally fine job. Rifling begins by mounting the barrel in the machine and setting the desired direction and rate of twist. Cut rifling and 5R are more time consuming and although more accurate. 4. , a receiver only. The Model 444 was introduced with a 12. See Figure 103 & 104. Randy Gregory of Medford, Wi. A long rod pulls a small hook in a hard-steel, bore-diameter cylinder, removing about 0. The Broughton 5c rifling looks alot like the rifling in a glock no sharp edges. Adding rifling to a bore that is sized for smoothbore use will likely impart little spin to the projectile and cause a lot of fouling from gas flowing between the projectile and the bore. « Reply #1 on: June 14, 2008, 03:21:54 AM ». doing this. The insert has a screw that locks the cutter rod in place. Mar 24, 2011. Chambering the Shilen I could tell by the chips on the reamer it was a softer blank. Scrape cutters are tools that are used in the process of rifling a barrel. impressed into the metal as the negatives of minute imperfections found on the rifling cutter’s surface ; these markings will be unique to each gun made - thus the marking will be individualizing characteristics to a single gun. Rifles and handguns have rifled barrels, that is, spiral grooves have been cut the length of the interior or bore of the barrel (Figure 2. ) Or, hammer forging can be used to form rifling. With this type of cutter, it is possible to set the depth of cut very precisely by rotating the bolt on the left side. Lawton did cut rifling, and also produced the worst barrel regardless of rifling method my gunsmith ever had in his shop with 33 years gunsmithing experience. At a practical level there is no difference as to the "extreme high quality, accuracy, and durability (lifespan)" of barrels made by CHF versus button rifled for AR15 type barrels. Rifling begins by mounting the barrel in the machine and setting the desired direction and rate of twist. The cutter can be of a single hook type or of a broached type. Rifling can be broached, single point cut, buttoned, hammer forged, or ECM( Electrochemical machined). Cut rifling . The sides of the grooves are parallel, but the sides of the lands are not and the 5R carries this to an extreme. Legit print (The Springfield 1903 Rifles by Brophy, pg. Precihole's Button Rifling machines incorporate the latest features to form precision grooves in small caliber weapon systems. I've also had a number of Rock Creek tubes on other rifles. Take your rotary cutter apart. The cost of the blank, of drilling the hole and of reaming and lapping are all extra. Rifling. Which rifling technique involves the use of cold-working to harden the interior of the barrel and permits the use of. The pressure exerted by a burning charge of powder in the chamber of a gun. Kolbe (past owner of Border Barrels) covers all the important processes: steel selection, hole drilling, hole reaming, and rifling (by various means). A good cut-rifled barrel will retail for $400 and up, while quality button-rifled barrels may start at $150. [Jeff Rodriguez] has been busy testing a feasible DIY method for rifling a barrel and has found some success using salt water, a power supply, wire, and 3D printed parts to create. Cut rifling and broach rifling both involve removing metal from the inside of the barrel, which produces “grooves” that lie in between uncut areas know as “lands. 005 to . It is ground to match most common right hand rifle twists inch or metric. Also no barrel maker can measure for residual stress in the material. 58 and . Patent 3,100,358 for what was named MicroGroove Rifling, which was a departure from the standard "Ballard," or cut rifling. The only cut rifled 1911 barrels I am aware of are Lissners. Inner surface of barrel of a gun leaves its class characteristic markings on a bullet passing through it; these markings are peculiar to each type. Broaching uses multiple cutting surfaces (cutters) mounted on the same axis to progressively remove metal. 500 Mag Rifling. You can see this in the image above . Broach Rifling: Very. Avoid the temptation to make your hook too agressive. * Cut-rifled barrels are drilled, then reamed to bore diameter. 104. Brophy's book on Marlins. 308. The whole stress relieving process takes 42 hours. Both methods can make junk or make match winning barrels. Minuteman. This required multiple iterative passes of a cutting head for each groove (at first this was done with a "scrape cutter", and later a "hook cutter"). Pick the blade carefully and put it on the holder. Button rifling which is much faster is the result of pulling or pushing a button with projections on. 308-inch bullets instead of . The quality of the barrels turned out by this method was very good, but it is a time-consuming process that slowed down production (the scrape cutter rifling process took about an hour to complete. Most of the weapons the firearms examiner will encounter have been rifled by one of these two methods, and mostly by the second. Check out the GROOVES above. depth of . The rod should spin freely in its handle, and the jag and patch should fit snugly in your barrel. Correct me if I'm wrong, but what made 5R famous was its enhancement over other geometries of cut-rifling . A bullet traveling down a 12-inch barrel with a 1:14” rate of twist will still be spun at the 1:14” rate. That is why . Cut Rifling Cut rifling is the oldest method of rifling a gun barrel. It was a success. This rifling proved itself over and over for decades on the national target match circuits. Cut rifling creates spiral grooves in the barrel by removing steel using some form of cutter. At the same time, the expansion of the fired cartridge. due to the superior throughput of hammer forging and button rifling. This process is done after there's a hole in the barrel blank. Rifling is only cut to about . grooving. Button rifled barrels are usually softer hardness wise to push / pull the button thru the bore. Cutter is made to SAAMI specs. usually much shallower than conventional cut rifling. Their single-point cut-rifling process delivers the most consistent and accurate results. This is the technique that puts the minimum amount of stress into a rifle barrel. It is best for barrels that do not require deep rifling grooves. The carbide button tool is attached to a rod of high tensile steel, and the other end of the long rod is attached to a. Some other rifling buttons are combo buttons that have both a rifling button and a finishing button or sizing button. . The answer is yes, it is worth sharpening a circular saw blade. The simplest types of rifling buttons merely cut the grooves into the barrel. Maybe . Very few hammer forged. This hook has to be pulled through the barrel’s bore on multiple passes before the process is complete. Back trench the cut along the inside of these lines. 2. The work hardening of the barrel steel caused by the button results in a bore surface that is denser than a cut surface. SPECS: 22 call land/groove diameter: . #2. Kr. #1. #14 · Aug 14, 2021. buttoned rifling actually forge the grooves and they are smooth because the button if lubricated and. We. In a cut barrel the twist rate is conrolled by turning the cutter as it passes down the barrel. This is why . Most custom barrel makers cut the rifling into their barrels, as opposed to button rifling which more or less cold forges the rifling. The scrape method was used for round ball barrels since they needed deeper grooves when. It's more susceptible to button slip (twist rate error) and displacing the material work hardens it and creates internal stresses. 308") so it would seem that it wouldn't take too much to make rifling but it is kinda important that it is twisted just right, that is the difficult part. Drilled barrel bores is still very much a thing. They charge more for it because it takes substantially longer to produce due to the way the rifling is imparted to. All of our barrels are manufactured using single-point cut-rifling and each and every barrel we make is thoroughly inspected and held to the same premium match grade standards, whether its an ammunition test barrel, a custom bolt action barrel or a ready-to-install finish chambered AR15. !f you look what is used. Occasionally during this process something goes wrong. As previously stated it is hard to get extra deep rifling to seal, and not burn up the patch. Hammer forging is also known as the "Appel process" or cold forming. Single-point rifling. As we noted in the previous post, Cut Rifling produces very accurate results, but it is very slow to manufacture as the rifling is cut little by little. Some folks think cut rifling can wear quicker due to the sharp interior surfaces. As a result, it is most commonly seen in . Cut Rifling, along with Button Rifling machines are for smaller calibers from 0. In order to produce rifling similar. If the chip is not the full width of the groove, it means there is a nick in the cutting edge, or your cut is not deep enough. This has been the old standby in terms of rifling because it nearly never. to the ratchet rifling shown above, you would have to "re-cut" the tops of the lands, I don't know of any barrel maker. Why because they don’t understand the tooling for cut rifling is one. The cut-rifling method removes metal from the surface of the bore to create the grooves using a single-bladed, hook-type cutter. A gun drill is basically a 1 axis machine with a special high pressure cooling/lube system. I used a Weaver brand picatinny scope base for a. I cut the shoe recess, 1-3/8 inch long about 1/2 way through the rod. There is a slightly higher bullet velocity in polygonal rifling and they are easier to clean than conventional/cut rifling. I personally think the whole cut rifled vs button rifled thing is over done and the merits of cut rifling and the downfalls of button rifling are often exaggerated. Now we will study a more modern technique called Broach Rifling. The barrel is accurate and has precision cut rifling with a twist rate of 1:10. It produces moderate amounts of stress in the steel, which can be stress-relieved and straightened. This rifling-machine post will still be here when you come back). This required multiple iterative passes of a cutting head for each groove (at first this was done with a "scrape cutter", and later a "hook cutter"). It would pretty easy to make a good low cost cutter using a CNC plasma with the pipe cutter attachment, and a half a day on the Bridgeport. Fairly sharp , (but not too sharp as to cut the patches) lands grip the best. Conversely, the scrape cutter has mu l ti-point cutters inset into the opposed sides that can scraped a minimal of two opposed grooves to all grooves at a time. A broach is merely a long tool with multiple cutting elements on it. Gun barrels are the most critical part of a quality firearm, and our products are hand-made by craftsmen experienced in both machine tooling and competitive shooting. The grooves are usually parallel in barrels while the sides of the lands are not. However, this situation will change as many firearms now being made are being rifled by newer methods which have the advantage of being. You wee left with a long spru that has to be manually cut off. Choose Options. With this high-tech method, strips of desired shape are placed inside the bore while the whole assembly is submerged in a salt solution. Pratt and Whitney then created rifling machines that would use a hydraulic ram to force a shaped carbide "button" ( actually a short rod) through the barrel. #10. The rifling itself is formed by four common methods. At a practical level there is no difference as to the "extreme high quality, accuracy, and durability (lifespan)" of barrels made by CHF versus button rifled for AR15 type barrels. The cutter removes approximately . This makes it expensive. Inspect the cutter for any damage or worn parts and ensure that all parts are in. Ballard rifling featured fewer grooves but they were more deeply cut into the barrel. This may be changing with the advent of contoured (5R) cut riflings. Invented in N uremberg around 1520, the cut-rifling technique creates spiral grooves in the barrel by removing steel using some form of cutter. On the phone he said I had a good reputation locally for turning out nice machine work and asked me if I wanted to learn the art of drilling, reaming, cut-rifling, & lapping barrels. This greatly improves the accuracy of the bullet over longer distances. Barrels are rifled using a left or right twist. What is Button Rifling? In button rifling, the “button” is actually a tool made of tungsten carbide. Osprey Barrel Works is a premier brand, 416RR CReS precision rifle blank. That’s in the tooling. Cut Rifling Machines (also known as Single Point Cut Rifling) cut spiral grooves in the barrel by machining steel using a hook cutter. If needed, hammer forging can form the chamber and throat as well as a fully profiled outer surface. The broach is a piece of steel alloy that provides strength. Button rifling introduces stress because it doesn't cut, it just literally pushes all the metal it doesn't. Couple 2x4s, some screws, a small stick of round bar, some clamps, and a cutter head that I'll machine. This plug should never be removed from the bore until its work is finished. Are you meaning to say that they use a button to form their rifling? Because a button doesnt cut and your claim they they use a button to cut is objectively incorrect. Notice there are two headspace reference dimensions for the chamber. Removes metal from the surface of the bore using a single-bladed hook cutter. A mandrel is pushed or pulled through the bore and displaces material into the shape of rifling. The cut-rifling method. The rifling process is a key part of barrel manufacturing, resulting in lands (bore) and grooves that create a spiral down the length of the barrel. Cut rifling is using the exact same cutter in order to impart the spiraling grooves present within rifling. with the catch being that we were always talking about cut-rifling. 60. Twist rate is also spot-on, on cut rifled tubes. Square bottom CUT rifling to . He used stress-relieved steel for all his barrels. Back trench the cut along the inside of these lines. “A single-point cutter imposes little stress on the blank,” John Krieger says. For. The discs are produced by milling away parts of a larger diameter stock piece, leaving the discs standing upright on the support rod. Don. S. 32 and . The GROOVES are a bigger diameter than The Caliber or Bore. It is threaded at the muzzle to 5/8 by 24 for the use of a muzzle brake or a suppressor but comes with a threaded cap. 22 caliber barrels or pellet guns. This sets us separate from the other barrel maker's out there that drill with a stationary drill with the barrel rotating. Broached rifling. They use a wooden rifling bench,with about a 3" diameter maple cylinder with the rifling grooves cut into it with hand tools. Ballard rifling came about during the years Marlin made Ballard rifles. An ordinary Glock pistol. During the search for rifling cutters I have found a lot information about rifling machines ( old and modern ). (Here’s where cut barrels jumped a way up on my list from button sticks. Building on a savage action, have an additional post in competition forum but figured I'd ask the barrel question here Guess wondering the accuracy difference one could expect out. 300 Blackout Barrels for 2022 Faxon Firearms . Please allow 3-5 business days from order placement to shipment to allow us time to contour. RIFLING CUTTER (SCRAPE TYPE) TO DEEPEN EXISTING GROOVES IN BARREL USING EXISTING RIFLING IS GUIDE. The smooth-bore barrels are attached to a rifling lathe after forging. The curved surface of the cutter holder opposite the working edge bears against the side of the barrel for support and alignment. Here's a breakdown of the 3 main types of rifling, Cut rifling, button rifling, and cold hammer forged, and what we believe are the benefits. The rifle is also available with an optional 20″ or 18″ barrel length as well as a muzzle brake if you so desire, but the recoil of this rifle is easily manageable. Rifling Buttons are Precision Carbide Tools for forming the rifling grooves and resizing the bore in gun barrels. 35 Remington microgroove rifled barrel. 6. It stands apart from most modern barrels’ six lands configuration. Equipping the barrel with the spiral grooves that spin-stabilize a bullet is the essential operation that defines an entire category of firearms. The most common is “button” rifling, where a roundish “button” with edges cut for grooves is pushed or pulled through a barrel to create the necessary pattern. When these marks are on the lands "only" it is from the drilling process before the final reaming to get the proper bore size. In a 50 caliber rifle, the cutter is ground to an exact radius to create a round shape that is a circle. Polygonal rifling. Although our machines are state-of-the-art, the process itself is the oldest and slowest method of rifling a barrel. Hammer-forged rifling starts with a reusable mandrel that carries the reverse image the entire length of the bore and uses it to produce the desired rifling profile. engineering. 010. As I recall, the scrape method took about an hour per barrel, whereas the button took 45 sec. Cal. The seller says, "its an early 70s gun, with ballard type rifling" Well, I for sure knew better, and should have not done it, but took his word and then looked at the actual rifling later. Rifling broach. It is best for barrels that do not require deep rifling grooves. 1. It will only cut the rifling leade. Cut Rifling – This is an older, more traditional method that isn’t commonly used today. Cut rifled tubes can be made a few Rc points harder which should help in longevity. Forged rifling. Click Arrow to Watch Krieger Barrels Video:Rifling broach. The ideal is to have the correct groove diameter, . This video shows the process of cut-rifled barrel-making by one of the world's best barrel manufacturers. All barrels are prelapped/honed before rifling and finish lapped after rifling. Today, four- and six-groove barrels are the most popular. The grooves cut around the shank of many of today’s bullets solve the problems associated. 0001” of material at each pass, thus requiring. Marlin appears a bit better designed - any thoughts pro / con ?The rifling head is a hollow cylinder, and is made of high-carbon steel with a slot for the cutter cut lengthwise, about two inches long, on one side. Drill and reamer marks are not removed by button rifling as they are with cut. The Castle 110 is fitted with a router that cuts the. A rifling button is kinda like a tailpipe expander. 4' stick of 4" SCH-40 PVC with a strip of something wrapped around it like a barber pole. You will find button and cut rifling in those arena's. The work hardening of the barrel steel caused by the button results in a bore surface that is denser than a cut surface. IMHO the real difficult part would be mastering how to. Scrape Cutter. How does button rifling compare to cut rifling? Button rifling is generally considered more cost-effective than cut rifling as it requires less time and labor. Brophy's book on Marlins. 005 to . e. You would not likely be controlling depth of cut in the groove via CNC (possible, but with exceedingly small mechanisms), so what you are talking about is one axis making the carriage travel and another axis making the tool rotate and a program telling how much rotation per travel -. It is essentially a negative image of the barrel, i. There are four ways to produce the grooves: Cut rifling. Bear Creek Arsenal. No additional stress on the barrel - no stress relief step is required. Regarding thoughts on 5r, an odd number of lands/grooves creates less stress on the bullet as it passes down the barrel and if memory serves correctly it also allows for better or more uniform gas seal with less stress on the bullet than even rifling count- add to that the. might as well throw canted lands and button/cut rifling into the mix. 218/. On my 3 groove barrel you can clearly see the leading edges of the lands being eaten away at. The lathe pushes a single cutter, attached to a long rod, through the bore, carving each land and groove. Using a small 1/8" chisel, carefully remove the wood from the inside the mortise to a depth of about 1/32" to 1/16". Button rifling is done by pulling a solid carbide forming die (referred to as a button) through the drilled and reamed barrel bore. Stress Relieve Oven with automated loading system. The cutter rests in the cutter box, a hardened steel cylinder made so it will just fit. The first was Vienna gunmaker Gaspard Kollner. Cut rifling is single point broach rifling, you are. The button tool is attached to a rifling head, which is in turn attached to a long rod of high tensile steel and the other end of the long rod is attached to a. The big bore . 6 x 0. We want a snu 2 fit. Only way I could get "blue" on the patch,. This required multiple iterative passes of a cutting head for each groove (at first this was done with a "scrape cutter", and later a "hook cutter"). The cut-rifling method removes metal from the surface of the bore to create the grooves using a single-bladed, hook-type cutter of groove width that is pulled through the cold barrel. Cut Rifling: The oldest method of rifling a barrel, the process removes metal from the bore using a single-blade, hook-type cutter. The cutter is adjusted to cut one- to two-thousandths of an. Before 1950 all Marlin barrels were made by drilling the bore, and then cutting the rifling one groove at a time on a sine-bar machine. Origin action hawk hill 6. 9-inch long barrel is made for the Glock 19 using super durable 416R Stainless Steel. The only exception to this rule is Forsyth style rifling with wide grooves, and narrow lands. After the rifling has been cut, clean the barrel of the gun and the rifling cutter carefully. There are two main rifling types, standard and polygonal. ) a hardened steel button can be used to make rifling, c. Custom Prefits - Ospreys. Also, a high level of skill is required to maintain the tooling. A real cut rifling machine is getting closer to a real 3 axis machine. Fig. In its traditional form, cut rifling may be described as a single-point cutting system using a “hook” cutter. 5 cm barrel 24 inch barrel (cut rifling hand lapped) this time lapua brass, CCI 450 primers, IMR4451 (41. This change in cutter geometry, along with several changes made to the machines themselves, have made the act of cut. Krieger cut-rifled barrels have set numerous world records and are favored by many top shooters. Do this preferably from the breech end to avoid damaging the barrel’s crown. The most common cut rifling method used in. This is why I always go back to a cut barrel being better than a button barrel. However, it introduces no additional stress to the barrel and tolerances can be kept tight. 5R is an improvement over conventional rifling by changing the shape and configuration of the lands and grooves. PC barrels are now button rifled and made by T/C. No need to worry about to hard to cut, or annealing after button rifling. Button rifling injects more as the 'button' pulled through the bore swaging the rilfing into a previously smooth surface. I am looking to build up a lever . Button rifling. How many grooves does a hook cutter make with one swipe? 1. 0001-inch per pass. The broach is fed down the barrel with a rotation that matches the twisting ground in the tool, with each progressive tooth increasing the depth of the cut. I was just pointing out that button rifling does induce more stress in a barrel than cut rifling, if that. The first barrels that were rifled were made by either forming the bore around a mandrel ( Damascus barrels) or , much later on, drilling the bore through a solid bar stock blank, and then cutting the rifling one groove at a time. Here's a breakdown of the 3 main types of rifling, Cut rifling, button rifling, and cold hammer forged, and what we believe are the benefits. A broach has mulitple cutters on it. Button barrels the twist is mostly controlled by the shape of the button and the twist rate can vary depending on many variables. The elliptical gears were to speed up the return of the cutter [the rifling rod passed thru the barrel with a scrape cutter and a tapered "needle" to raise same]. Unlike the above-mentioned barrel makers who usually specialize in one rifling method (either button or single cut rifling), Rock Creek offers either rifling solution. The cutting tool is attached to a cutter box, which. Pistols with polygonal rifling have smaller bore diameters than pistols with traditional rifling. . 6K fps. It takes a LOT of effort to pull a . You may be surprised to learn that cut-rifling is probably the oldest method of rifling a barrel. In addition, the article describes a new (and somewhat radical) method, Cation Rifling, which employs acid to etch. As previously mentioned, different types of steels are. During the 20th century, new swaging methods such as button. One of the main purposes of Microgroove rifling was to help the bullet seal off the bore better to keep the expanding gas behind the bullet, and. The drawbar attaches to the worm wheel and to the rifling cutter with precision tapered cross pins. For background, current thought is to build a 600 yard f classer, right now looking at a 260 AI or variant thereof. Generally, blades that cost $50 or more are worth sharpening while it is better to replace cheaper,. There are two main rifling types, standard and polygonal. Single Point Cut Rifling. While the number of companies offering reboring has decreased considerably in the past few decades, the few remaining in the U. Conventional rifling, while effective, can be improved upon in two ways. Hammer forging also work hardens the rifling. Like all old technologies, cut rifling is slow and requires a high level of skill to make and maintain the tooling. The rifling is always putting a fresh bite on the bullet as it goes down the bore of the barrel. The barrel also has a flush crown cut, which. 300" that makes the American . Cut Rifling – This is an older, more traditional method that isn’t commonly used today. The Different Methods of Barrel Rifling. 62 – 1/66 – 1/72. Images of Cut-Rifling process courtesy Accurate Shooter Rifling is usually expressed as a twist rate; that is the length required to complete a full revolution along the horizontal access. The Foam Shop is committed to reducing the waste that ends up in our local landfills. Barrel Twist Rate – is the inches a bullet needs to travel in order to make a complete revolution. Even though a button rifled barrel typically gets restressed relieved again after button rifling there are no guarantees. I have a late Remington SBL and a Ruger SBL and at the range they shoot neck and neck. To make a rifled barrel, normally a hole is deep-drilled in a steel bar. Cut Rifling Cut rifling is the oldest method of rifling a gun barrel. The rifling process is a key part of barrel manufacturing, as rifle and pistol barrels require rifling to shoot accurately. 35 Remington microgroove rifled barrel. Describe polygonal rifling: Polygonal rifling is formed by hammering the barrel from the outside and is used to describe bores with unconventional rifling. A rifling broach is a long rod with a series of cutter discs perpendicular to the axis of the rod. this single point cut rifling process requires a single cutter to make 120 individual cuts to accurately rifle each bore. To date, Criterion’s button rifled barrels have set. The quality of the barrels turned out by this method was very good, but it is a time-consuming process that slowed down production (the scrape cutter rifling process took about an hour to. 45 / 70 as a close support Scout rifle. 30-30 rifles had MG rifling. Fig. "Up until a couple years ago the PC 500 mags did indeed have Lothar Walther polygon rifling. com. 630″~1. We proudly create rifle barrels for F-Class competitors,. Tooling – gundrills, reamers, rifle buttons. Rifling twist rate can be changed. When running properly a carbide cutter is capable of rifling 10-20 barrels before resharpening. Cut rifling creates the spiral grooves in the barrel by removing steel with the use of a “hook cutter”. Starting with a pilot section, a rifling broach has multiple rings of cutters whose axial cross-sections match the rifling layout. There’s a long-standing debate in the firearm industry about which rifling methodology provides the best performance. Lawton did cut rifling, and also produced the worst barrel regardless of rifling method my gunsmith ever had in his shop with 33 years gunsmithing experience. Gun barrels are the most critical part of a quality firearm, and our products are hand-made by craftsmen experienced in both machine tooling and competitive shooting. Invented in Nuremberg around 1520, the cut-rifling technique creates spiral grooves in the barrel by removing steel using some form of cutter. Even if scrape cutter rifling requires less time to produce grooves, both processes are time-consuming and incompatible with large-scale manufacture since the cutter may require several sharpening or even replacement (Biasotti, 1981; Bonfanti, 1997).