“Koenig” (or König) means “king” in German. That is indeed appropriate for Doug Koenig, 18-Time Bianchi Cup winner, who is now starting to conquer the rifle world as well. Koenig, considered by many to be the best action pistol shooter on the planet, proved he’s an ace with rifles too, as he recently won two PRS matches in Production Division. Koenig, Captain of Team Ruger, was shooting a Ruger Precision Rifle (RPR), chambered in 6mm Creedmoor. Notably, Production Division limits rifles to $2000.00 for the gun ($4000.00 overall with scope). You can buy an RPR for around $1100.00 typically ($795.00 at GrabAGun), so Koenig was shooting against competitors with rifles that cost nearly twice as much. That’s impressive.
Koenig Wins Production Class at two Spring PRS Matches
Koenig took home a pair of Production Division titles at this year’s WAR Rifles Shootout and MAP Spring Shootout Precision Rifle Series (PRS) matches.
With a final score of 128.00 and a time of 58.51, team captain Doug Koenig took first place in Production Division at the WAR Rifle Shootout PRS match in Mount Victoria, MD. The WAR Rifle Shootout has a challenging 22-stage course of fire. Along with winning Production Division, Koenig also finished twelfth overall. “The tough course of fire and 15-25 mph winds at the War Rifle match were brutal, but my Precision Rifle, equipped with a Leupold VX-3i LRP and loaded with Hornady ammunition, continued to perform,” said Koenig.
Koenig then secured another Production Division win at the MPA Spring Shootout held at the Arena Training Facility in Blakely, GA with a final score of 173.00 and a time of 58.89. “The MPA match had some long shots out to 800-1356 yards, but my factory rifle got the job done and helped me win my third production class title in a row. That proves you don’t need to spend a fortune to get started in PRS competition.”
According to PRS standards, Production Division rifles are not permitted to be altered or improved in any way from the original factory configuration, and the retail price may not exceed $2,000.
Pre-Fit Barrel Options for the Ruger Precision Rifle
While PRS Production Division competitors like Koenig must stick with factory barrels, there’s no law that says you can’t upgrade your own RPR that’s not used in PRS matches. A barrel swap is probably the single best hardware upgrade you can make. A new custom barrel will improve inherent accuracy and shot-to-shot consistency. Krieger Barrels offers Pre-Fit barrels for the RPR in many popular chamberings including 6XC, 6mm Creedmoor, .243 Win, 6.5 Creedmoor, 6.5 PRC, and .308 Win. These “Drop-In Ready” barrels come finish-chambered and threaded to fit the Ruger action, with factory-spec muzzle threads. The Ruger barrel attachment system allows correct headspace with a pre-chambered barrel. Krieger explains: “Thanks to Ruger’s proprietary barrel nut design, a competent gunsmith will be able to swap out your barrel using an AR15 barrel wrench and proper headspace gauges.”
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Put the same load in a variety of barrels (with the same length and chamberings) and you’ll see a wide variance in muzzle velocity. In fact, it’s not unusual to see up to 100 fps difference from one barrel to the next. We demonstrated this with a comparison test of Lapua factory ammo.
Chron Testing Lapua Factory Ammo
At our Southern California test range some years ago, we chronographed Lapua 105gr 6mmBR factory ammo in three different 8-twist barrels of similar length. The results were fascinating. Lapua specs this ammo at 2790 fps, based on Lapua’s testing with its own 26″ test barrel. We observed a speed variance of 67 fps based on tests with three aftermarket barrels.
Barrel Velocity Variance
Brand ‘S’ and Brand ‘PN’ were pre-fit barrels shot on Savage actions. Brand ‘K’ was fitted to a custom action. All test barrels were throated for the 100-108 grain bullets, though there may have been some slight variances in barrel freebore. With a COAL of 2.330″, the rounds were “jumping” to the rifling in all barrels.
Among the four barrels, Brand ‘PN’ was the fastest at 2824 fps average — 67 fps faster than the slowest barrel. Roughly 10 fps can be attributed to the slightly longer length (27″ vs. 26″), but otherwise this particular barrel was simply faster than the rest. (Click Here for results of 6mmBR Barrel Length Velocity Test).
IMPORTANT: Results Are Barrel-Specific, Not Brand-Specific
These tests demonstrate that the exact same load can perform very differently in different barrels. We aren’t publishing the barrel-makers’ names, because it would be wrong to assume that ‘Brand X’ is always going to be faster than ‘Brand Y’ based on test results from a single barrel. In fact, velocities can vary up to 100 fps with two identical-spec barrels from the SAME manufacturer. That’s right, you can have two 8-twist, 26″ barrels, with the same land-groove configuration and contour, from the same manufacturer, and one can be much faster than another.
Don’t Demand More Than Your Barrel Can Deliver
We often hear guys lament, “I don’t get it… how can you guys get 2900 fps with your 6BRs and I can only get 2840?” The answer may simply be that the barrel is slower than average. If you have a slow barrel, you can try using more powder, but there is a good chance it may never run as fast as an inherently fast barrel. You shouldn’t knock yourself out (and over-stress your brass) trying to duplicate the velocities someone else may be getting. You need to work within the limits of your barrel.
Factory Ammo Provides a Benchmark
If you have a .223 Rem, 6mmBR, .243 Win, 6.5×47 Lapua, 6.5 Creedmoor, 6.5×55, .308 Win, 30-06, or .338 LM Rifle, we recommend you buy a box of Lapua factory-loaded ammo. This stuff will shoot great (typically around half-MOA), and it can give you a baseline to determine how your barrel stacks up speedwise. [Editor’s NOTE: The original test was conducted in 2008. The velocity of current-production Lapua factory ammo might be higher or lower, so your results may vary.]
When you complete a new 6mmBR rifle, it’s definitely smart to get a box of the factory ammo and chronograph it. That will immediately give you a good idea whether you have a slow, average, or fast barrel. Then you can set your velocity goals accordingly. For example, if the factory 6BR ammo runs about 2780-2790 fps in your gun, it has an average barrel. If it runs 2820+ in a 26″ barrel (or 2835 fps in a 28″), you’ve got a fast tube.
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You’ve probably heard of cut-rifling, but did you know this process was invented in Germany nearly 500 years ago? Read on to learn more about how a cut-rifled barrel is made…
The cut-rifling process, used by leading barrel-makers such as Bartlein, Border, Brux, Krieger, and Obermeyer, can yield a very high-quality barrel with a long useful life. Cut-rifled barrels have been at the top in short- and long-range benchrest competition in recent years, and cut-rifled barrels have long been popular with F-Class and High Power shooters.
You may be surprised to learn that cut-rifling is probably the oldest method of rifling a barrel. Invented in Nuremberg around 1520, the cut-rifling technique creates spiral grooves in the barrel by removing steel using some form of cutter. In its traditional form, cut rifling may be described as a single-point cutting system using a “hook” cutter. The cutter rests in the cutter box, a hardened steel cylinder made so it will just fit the reamed barrel blank and which also contains the cutter raising mechanism.
Above is a computer animation of an older style, sine-bar cut-rifling machine. Some machine features have been simplified for the purposes of illustration, but the basic operation is correctly shown. No, the cut-rifling machines at Krieger don’t use a hand-crank, but the mechanical process shown in this video is very similar to the way cut-rifling is done with more modern machines.
Read About Cut-Rifling Process at Border-Barrels.com
To learn more about the barrel-making process, and cut-rifling in particular, visit FirearmsID.com. There you’ll find a “must-read” article by Dr. Geoffrey Kolbe: The Making of a Rifled Barrel. This article describes in detail how barrels are crafted, using both cut-rifling and button-rifling methods. Kolbe (past owner of Border Barrels) covers all the important processes: steel selection, hole drilling, hole reaming, and rifling (by various means). You’ll find a very extensive discussion of how rifling machines work. Here’s a short sample:
“At the start of World War Two, Pratt & Whitney developed a new, ‘B’ series of hydraulically-powered rifling machines, which were in fact two machines on the same bed. They weighed in at three tons and required the concrete floors now generally seen in workshops by this time. About two thousand were built to satisfy the new demand for rifle barrels, but many were broken up after the war or sold to emerging third world countries building up their own arms industry.
Very few of these hydraulic machines subsequently became available on the surplus market and now it is these machines which are sought after and used by barrel makers like John Krieger and ‘Boots’ Obermeyer. In fact, there are probably less of the ‘B’ series hydraulic riflers around today than of the older ‘Sine Bar’ universal riflers.
The techniques of cut rifling have not stood still since the end of the war though. Largely due to the efforts of Boots Obermeyer the design, manufacture and maintenance of the hook cutter and the cutter box have been refined and developed so that barrels of superb accuracy have come from his shop. Cut rifled barrel makers like John Krieger (Krieger Barrels), Mark Chanlyn (Rocky Mountain Rifle Works) and Cliff Labounty (Labounty Precision Reboring)… learned much of their art from Boots Obermeyer, as did I.” — Geoffrey Kolbe
Video find by Boyd Allen. Archive photos from Border-Barrels.com. In June 2013, Birmingham Gunmakers Ltd. acquired Border Barrels. Dr. Geoffrey Kolbe has set up a new company called BBT Ltd. which produces chamber reamers and other gunsmithing tools and gauges. (Thanks to L. Holland for the Kolbe update).
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“At the start of World War Two, Pratt & Whitney developed a new, ‘B’ series of hydraulically-powered rifling machines, which were in fact two machines on the same bed. They weighed in at three tons and required the concrete floors now generally seen in workshops by this time. Very few of these hydraulic machines subsequently became available on the surplus market and now it is these machines which are sought after and used by barrel makers like John Krieger and ‘Boots’ Obermeyer. In fact, there are probably less of the ‘B’ series hydraulic riflers around today than of the older ‘Sine Bar’ universal riflers.” — Geoffrey Kolbe, Border Barrels.
How Krieger Builds Barrels
This video shows the process of cut-rifled barrel-making by Krieger Barrels, one of the world’s best barrel manufacturers. Krieger cut-rifled barrels have set numerous world records and are favored by many top shooters. The video show the huge, complex machines used — bore-drilling equipment and hydraulic riflers. You can also see how barrels are contoured, polished, and inspected.
Click Arrow to Watch Krieger Barrels Video:
For anyone interested in accurate rifles, this is absolutely a “must-watch” video. Watch blanks being cryogenically treated, then drilled and lathe-turned. Next comes the big stuff — the massive rifling machines that single-point-cut the rifling in a precise, time-consuming process. Following that you can see barrels being contoured, polished, and inspected (with air gauge and bore-scope). There is even a sequence showing chambers being cut.
Here is a time-line of the important barrel-making processes shown in the video. You may want to use the “Pause” button, or repeat some segments to get a better look at particular operations. The numbers on the left represent playback minutes and seconds.
Krieger Barrel-Making Processes Shown in Video:
00:24 – Cryogenic treatment of steel blanks
00:38 – Pre-contour Barrels on CNC lathe
01:14 – Drilling Barrels
01:28 – Finish Turning on CNC lathe
01:40 – Reaming
01:50 – Cut Rifling
02:12 – Hand Lapping
02:25 – Cut Rifling
Based on the questions we get on a daily basis on our 800 (Customer Support) line, twist is one of the most misunderstood subjects in the gun field. So let’s look deeper into this mystery and get a better understanding of what twist really means.
When you see the term 1:14″ (1-14) or 1:9″ twist, just exactly what does this mean? A rifle having a 1:14″ twist means the bullet will rotate one complete revolution every fourteen inches of the barrel. Naturally a 1:9″ turns one time every nine inches that it travels down the barrel. Now, here’s something that some people have trouble with. I’ve had calls from shooters thinking that a 1:14″ twist was faster than a 1:9″ because the number was higher with the 1:14″. The easiest way to remember this is the higher the number, the slower the twist rate is.
Now, the biggest misconception is that if a shooter has a .223 with a 1:8″ twist, his rifle won’t stabilize a 55gr bullet or anything lighter. So let’s look at what is required. The longer a bullet is for its diameter, the faster the twist has to be to stabilize it. In the case of the .223 with a 1:8″ twist, this was designed to stabilize 80gr bullets in this diameter. In truth the opposite is true. A 1:8″ will spin a 55gr faster than what is required in order to stabilize that length of bullet. If you have a bullet with good concentricity in its jacket, over-spinning it will not [normally] hurt its accuracy potential. [Editor’s Note: In addition, the faster twist rate will not, normally, decrease velocity significantly. That’s been confirmed by testing done by Bryan Litz’s Applied Ballistics Labs. There may be some minor speed loss.]
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.
Think of it like tires on your truck. If you have a new set of tires put on your truck, and they balance them proper at the tire shop, you can drive down a street in town at 35 MPH and they spin perfect. You can get out on the highway and drive 65 MPH and they still spin perfect. A bullet acts the same way.
Once I loaded some 35gr HP bullets in a 22-250 Ackley with a 1:8″ twist. After putting three shots down range, the average velocity was 4584 FPS with an RPM level of 412,560. The group measured .750″ at 100 yards. This is a clear example that it is hard to over-stabilize a good bullet.
Twist-rate illustration by Erik Dahlberg courtesy FireArmsID.com. Krieger barrel photo courtesy GS Arizona.
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M-K IIA2 GEN2 Tactical Trigger from The Wisconsin Trigger Co.
Gear Review by Johnny Fisher
Do you shoot an AR-platform rifle? Here’s an excellent trigger upgrade option that has recently returned to the marketplace. The Wisconsin Trigger Company (WITC) has resumed production of the legendary Milazzo-Krieger M-K II trigger for the AR-platform rifles. Not merely marketing a replica of the original Milazzo-Krieger design, Wisconsin Trigger now offers an enhanced, drop-in version called the M-K IIA2. An easy install, the Milazzo-Krieger trigger drops in with no special tools or machining required (and no modification of the safety selector switch).
For those who are looking for an extremely crisp AR15 trigger that closely mirrors the “feel” of a finely tuned M1 / M14 trigger, this trigger might be the solution. The first stage is exceptionally clean and smooth due to a proprietary diamond-grinding process. I felt that the first stage travel was longer than a Geissele, but many guys will prefer that. Upon reaching the very noticeable and defined “wall” of the second stage, a further increase of pressure provides the instantaneous snap one looks for in a high-quality trigger — complete with a total absence of anything resembling creep or slop.
If you follow the instructions in the box and watch WITC’s informative how-to videos, installation of this trigger is extremely straightforward, requiring no special tools or fitting.
As supplied straight from the factory, the first stage requires about 2.25 pounds of take-up before encountering “the wall” of the second stage. For this purpose of this review and to ensure “making weight” in CMP Service Rifle Competitions, the (white) 5-lb. disconnector spring was used. The weight of the second stage came in right at an extremely repeatable 5 lb. 3 oz. (averaging +/- 1.5 oz.) for a ratio of about 40/60 between the two.
Upon release of the hammer, the disconnector reset is decidedly short. National Match shooters in particular will appreciate the very short but easy-to-recognize trigger reset during rapid-fire strings.
Tuning the Trigger Before Installation
As with most National Match-grade triggers on the market, the Millazo-Krieger utilizes proprietary pins that come supplied with this unit. They must be used for final installation and are purposely oversized to a specific diameter for a very snug fit. This is to ensure the trigger and hammer rotate solely on the pins, as opposed to the pins eventually rotating inside the receiver. It is best to use standard sized mil-spec trigger and hammer pins for the setting of tensions (trigger weight) before final installation to help avoid undue wear to the receiver pin holes. Final adjustment of second-stage pull weight must be done BEFORE final installation.
It is recommended to first set the amount of desired disconnector engagement by performing a very simple process that is detailed in the included installation instructions from the TOP of the trigger. The swapping out of disconnector springs and final tuning of the second stage can then be done, but only from UNDERNEATH a disassembled trigger.
The disconnector tensioning springs are easily swapped out by removing the spring plug from the bottom of the trigger housing that exposes the spring pocket. After inserting the desired weight spring, the spring plug must be installed at least flush with the bottom of the trigger housing. Installing it deeper will add trigger pull weight on the second stage. Installing it too shallow will interfere with trigger movement.
Transferable Warrnty:
The Wisconsin Trigger Company offers a full lifetime warranty to all unaltered parts of its triggers. This lifetime warranty is fully transferable when the trigger is sold to a new user! When have you heard of an AR component manufacturer with a transferable warranty — we’re impressed.
Not just a retailer, John Scandale of Keystone Accuracy is a distributor of these triggers. He currently has many in stock and for sale at a very special introductory price.
What Comes in the Box:
The $265.75 trigger kits come complete with everything you need: Trigger unit assembly, trigger return spring, full strength hammer spring, two proprietary oversized trigger & hammer pivot pins and three disconnector tensioning springs (3.25 lb., 4.5 lb., 5.0 lb.). Also included is a comprehensive installation manual, a color-coded disconnector spring selection chart, some promotional items, and the lifetime warranty card.
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SHOT Show offers a unique opportunity to see a host of new products AND reconnect with old friends in the shooting world. We met with our friends John Krieger (Krieger Barrels), Ian Kelbly (Kelblys.com), Dave Kiff (PT&G), and Eric Stecker (Berger Bullets). On SHOT Show Day One we saw many interesting items, including a new $1500.00, 15-60x52mm comp scope from Vortex and the amazing Bix’n Andy Elypse action. That 15-60X Vortex should prove a great choice for F-Class competition and the Elypse “raises the bar” for lightweight benchrest actions.
Everyone involved in long-range target shooting should check out this New Vortex “Golden Eagle” 15-60x52mm scope. It offers a 4X zoom ratio with 60X max magnification, with an affordable street price of around $1500.00. That undercuts the competition from other major brands by hundreds of dollars. Two reticle options will be offered, a fine cross-hair and one with MOA-based hold-over lines. We’ll provide a more complete report soon….
Howa — Mini-Action Bolt Gun
We finally got our hands on the Mini-action Howa, a very nice little rifle. I immediately noticed that the bolt is extremely smooth — really nice. The HACT 2-stage trigger is excellent — just about perfect for a varmint rifle. The action is nearly an inch shorter than a conventional “short action” so bolt movement is shorter. The rifle is currently offered in .204 Ruger and .223 Remington, and Howa may release a .222 Remington, 6.5 Grendel and 7.62×39 version in the future. Street price on this rifle is around $600.00. I give this rifle two thumbs up, way up. I want one.
Kelbly’s — New Composite GRS Stocks
Kelbly’s is the North American distributor for GRS stocks from Norway. For 2016 GRS has introduced advanced composite stocks. These share the ergonomic design of GRS wood stocks, but offer greater strength, rigidity, and durability. If you are looking for an advanced composite-matrix stock for hunting and tactical applications, you should check out this new GRS. We were very impressed.
Bix’n Andy — Titanium Elypse Action
This may be the most sophisticated benchrest action ever created. The new Bix’n Andy Elypse action will be offered in both stainless and Titanium (shown above). The action features an elliptical profile and a drop port. The trigger, sold separately, is superb, absolutely superb. There are many unique features, such as the flared loading port ramp and easy-change bolt handle. This is truly the Rolls-Royce of precision actions.
Shilen — AR and Savage Drop-in Barrels
We visited the Shilen booth and chatted with Wade Hull, Shilen’s President. Wade explained that Shilen now offers a variety of Drop-in Barrels for Savages as well as “large-format” ARs (AR10 type rifles in 308-family chamberings). Wade also noted that Shilen has streamlined its production process, so wait-time on chambering work has been reduced significantly.
Stocky’s Stocks — New 3D-Printed Prototype Stock
3D Printing and Rapid Prototyping has come to the gunstock world. Stockys Stocks showed off a high-tech 3D-printed prototype of its new tactical stock with removable cheekpiece. We also checked out Stocky’s impressive Long Range composite stocks. Very strong, and very rigid, these stocks feature a CNC-milled aluminum bedding block. These are a stunning value for just $199.99.
RAS Tuners — Combo Tuner + Muzzle Brake
Tuners work — though it may take a bit of time and effort to dial in your tune. The RAS Tuner system combines a sensitive tuner with a removable muzzle brake. There are systems for ARs as well as bolt guns. The inventor of the RAS says he has seen significant reductions in group size.
Tactical Solutions — High-Bling Rimfire Rifles and Pistols
If bling is your thing, then Idaho-based Tactical Solutions has you covered. This company offers a wide variety of firearms including .22 LR rimfire target pistols and rifles. The rifle in this photo is configured with a permanent barrel extension that makes it ATF-compliant. But the actual barrel is threaded below the barrel extension so you can add a suppressor and still have a short overall-length “fun gun”.
Hygenall — LeadOff Products
Anyone who does a lot of shooting may be exposed to lead residues. Lead is a tough substance to remove from human skin. We chatted with the scientists who created these LeadOff products and were quite impressed. The product uses sophisticated chemistry to “grab and remove” the lead molecules on your skin. This product has earned health agency certifications.
Champion — Plinking Targets for Fun Shooting
Among all the “Operator-ready” Black Rifles and Tactical gear, it was nice to see a display dedicated to the simple fun of shooting. As kids, we all started our shooting careers plinking with a BB Gun or a simple rimfire rifle. Champion makes a variety of reactive targets that are great for plinking.
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Here’s something you’ve probably never seen before — a liquid-cooled benchrest rifle. No, this is not just a crazy experiment. This gun, built by Joel Pendergraft, produced a 10-shot, 3.044″ group that is still listed as the International Benchrest Shooters (IBS) 1000-Yard Heavy Gun record. Using this water-cooled 300 Ackley Improved, Joel shot the record group in April 2009 at Hawks Ridge, NC. This monster features a 12-twist, 4-groove Krieger barrel. Joel shot BIB 187gr flat-based bullets in Norma brass, pushed by a “generous amount” of Alliant Reloder 25 and Federal 210M primers.
This 3.044″ 10-shot group was a remarkable accomplishment, breaking one of the longest-standing, 1000-yard World Records.
Pendergraft was modest after his notable achievement: “What makes this so very special is to be able to celebrate the accomplishment with all of my shooting friends[.] A good friend once said that records are shot when preparation and opportunity meet. I feel blessed to have personally had the opportunity. The preparation we can individually work on and achieve but the opportunity only comes to a few. Those of you that compete in long range competition will know what I mean.”
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Have you ever wondered how a cut-rifled barrel is made? This process, used by leading barrel-makers such as Bartlein, Border, Brux, Krieger, and Obermeyer, can yield a very high-quality barrel with a long useful life. Cut-rifled barrels have been at the top in short- and long-range benchrest competition in recent years, and cut-rifled barrels have long been popular with F-Class and High Power shooters.
You may be surprised to learn that cut-rifling is probably the oldest method of rifling a barrel. Invented in Nuremberg around 1520, the cut-rifling technique creates spiral grooves in the barrel by removing steel using some form of cutter. In its traditional form, cut rifling may be described as a single-point cutting system using a “hook” cutter. The cutter rests in the cutter box, a hardened steel cylinder made so it will just fit the reamed barrel blank and which also contains the cutter raising mechanism.
Above is a computer animation of an older style, sine-bar cut-rifling machine. Some machine features have been simplified for the purposes of illustration, but the basic operation is correctly shown. No, the cut-rifling machines at Krieger don’t use a hand-crank, but the mechanical process shown in this video is very similar to the way cut-rifling is done with more modern machines.
Read About Cut-Rifling Process at Border-Barrels.com
Read About Cut-Rifling Process at Border-Barrels.com
To learn more about the barrel-making process, and cut-rifling in particular, visit FirearmsID.com. There you’ll find a “must-read” article by Dr. Geoffrey Kolbe: The Making of a Rifled Barrel. This article describes in detail how barrels are crafted, using both cut-rifling and button-rifling methods. Kolbe (past owner of Border Barrels) covers all the important processes: steel selection, hole drilling, hole reaming, and rifling (by various means). You’ll find a very extensive discussion of how rifling machines work. Here’s a short sample:
“At the start of World War Two, Pratt & Whitney developed a new, ‘B’ series of hydraulically-powered rifling machines, which were in fact two machines on the same bed. They weighed in at three tons and required the concrete floors now generally seen in workshops by this time. About two thousand were built to satisfy the new demand for rifle barrels, but many were broken up after the war or sold to emerging third world countries building up their own arms industry.
Very few of these hydraulic machines subsequently became available on the surplus market and now it is these machines which are sought after and used by barrel makers like John Krieger and ‘Boots’ Obermeyer. In fact, there are probably less of the ‘B’ series hydraulic riflers around today than of the older ‘Sine Bar’ universal riflers.
The techniques of cut rifling have not stood still since the end of the war though. Largely due to the efforts of Boots Obermeyer the design, manufacture and maintenance of the hook cutter and the cutter box have been refined and developed so that barrels of superb accuracy have come from his shop. Cut rifled barrel makers like John Krieger (Krieger Barrels), Mark Chanlyn (Rocky Mountain Rifle Works) and Cliff Labounty (Labounty Precision Reboring)… learned much of their art from Boots Obermeyer, as did I.” — Geoffrey Kolbe
Video find by Boyd Allen. Archive photos from Border-Barrels.com. In June 2013, Birmingham Gunmakers Ltd. acquired Border Barrels. Dr. Geoffrey Koble continues to work for Border Barrels, which maintains operations in Scotland.
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Forum member Eric has built an innovative specialty pistol for long-range benchrest. The gun is chambered in 6.5-284 and built for IBS 1000-yard shooting. Eric originally built the gun with a 3″-wide fore-end, then decided to go with a 6″-wide offset design since the IBS no longer restricts Light Gun Forearms to three inches. Eric explained: “After building the 3″-wide stock I looked at the IBS 1000-yard benchrest rules and found out that there was not a width limit and rails were allowed for a Light Gun stock. I set out to design a 6″ version. I was thinking it should be offset also to help control torque and track straighter. I had a new 6.5mm, 1:8.5″ twist, 1.250″ HV-contour Krieger barrel. I chambered the barrel for 6.5-284 and bedded the stock.”
Eric feeds his pistol Sierra 142gr MatchKings with a load of 51.0 grains of H4831sc. Estimated muzzle velocity with this load is 2900 fps — respectable speed from the short barrel. The gun tracks remarkably well, with very little torque effect, as you can see in the video below.
After initial testing, Eric added a muzzle brake to the barrel. This tamed the recoil considerably. To learn more about Eric’s long-range 6.5-284 pistol, visit our Shooters Forum and READ this POST. To see more videos of the pistol in action (with muzzle brake), visit Eric’s PhotoBucket Album.
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Krieger Barrels Inc. is a family-run business. Founder John Krieger now works with two of his sons in the business, Andrew (“Andy”) and Mark. At SHOT Show 2014 we had a chance to chat with John and Andy. John told us that he is very proud to work with his two sons. He said that Andy, who has a degree in engineering, brings an important skill set and a new level of scientific expertise to the business. On his part, Andy says that his father is a “great boss… and the best teacher you could have”. Meet this father and son barrel-making team in this short video.
John Krieger and Andrew Krieger
How does Krieger Barrels produce such a great product year in and year out? It takes a lot of highly-skilled labor and some serious machinery to produce outstanding cut-rifled barrels. To illustrate the barrel-making process, Krieger has produced a fascinating video, filmed at Krieger’s production facility in Richfield, Wisconsin. This video shows the process of single-point, cut-rifled barrel-making start to finish. If you love big, powerful machines, you’ll enjoy this video. Its really quite amazing to see all that’s involved in the production of cut-rifled barrels.
How Krieger Barrels Are Made (MUST-WATCH video — one of the best we’ve ever featured).
For anyone interested in accurate rifles, this is absolutely a “must-watch” video. Watch blanks being cryogenically treated, then drilled and lathe-turned. Next comes the big stuff — the massive rifling machines that single-point-cut the rifling in a precise, time-consuming process. Following that you can see barrels being contoured, polished, and inspected (with air gauge and bore-scope). There is even a sequence showing chambers being cut.
Here is a time-line of the important barrel-making processes shown in the video. You may want to use the “Pause” button, or repeat some segments to get a better look at particular operations. The numbers on the left represent playback minutes and seconds.
Sometimes you’ll get a barrel that doesn’t stabilize bullets the way you’d anticipate, based on the stated (or presumed) twist rate. A barrel might have 1:10″ stamped on the side but it is, in truth, a 1:10.5″ twist or even a 1:9.5″. Cut-rifled barrels, such as Kriegers and Bartleins, normally hold very true to the specified twist rate. With buttoned barrels, due to the nature of the rifling process, there’s a greater chance of a small variation in twist rate. And yes, factory barrels can be slightly out of spec as well.
Before you purchase a bunch of bullets and set off to develop loads it’s wise to determine the true twist rate of your new barrel. Sinclair International, in its Reloading Press Blog provides a simple procedure for determining the actual twist rate of your barrel. Read on to learn how….
How Twist Rate Affects Bullet Stability
Most of you know that the twist of the rifling in the barrel is what puts spin on the bullet. As a bullet is pushed down the barrel and compressed into the rifling, the bullet follows the path or twist of the rifling. The combination of velocity and bullet spin is what stabilizes the bullet. Finding the twist rate for your barrel will help you in selecting appropriate weight bullets for your firearm. Remember, the general rule is that the faster the twist rate for a given caliber, the longer the bullet (of that caliber) you will be able to stabilize. (Generally speaking, a longer bullet will also be a heavier bullet, but the bullet geometry dictates the needed twist rather than the weight per se.)
Determining Barrel Twist Rate Empirically
Twist rate is defined as the distance in inches of barrel that the rifling takes to make one complete revolution. An example would be a 1:10″ twist rate. A 1:10″ barrel has rifling that makes one complete revolution in 10 inches of barrel length. Rifle manufacturers usually publish twist rates for their standard rifle offerings and custom barrels are always ordered by caliber, contour, and twist rate. If you are having a custom barrel chambered you can ask the gunsmith to mark the barrel with the twist rate.
Sinclair’s Simple Twist Rate Measurement Method
If are unsure of the twist rate of the barrel, you can measure it yourself in a couple of minutes. You need a good cleaning rod with a rotating handle and a jag with a fairly tight fitting patch. Utilize a rod guide if you are accessing the barrel through the breech or a muzzle guide if you are going to come in from the muzzle end. Make sure the rod rotates freely in the handle under load. Start the patch into the barrel for a few inches and then stop. Put a piece of tape at the back of the rod by the handle (like a flag) or mark the rod in some way. Measure how much of the rod is still protruding from the rod guide. You can either measure from the rod guide or muzzle guide back to the flag or to a spot on the handle. Next, continue to push the rod in until the mark or tape flag has made one complete revolution. Re-measure the amount of rod that is left sticking out of the barrel. Use the same reference marks as you did on the first measurement. Next, subtract this measurement from the first measurement. This number is the twist rate. For example, if the rod has 24 inches remaining at the start and 16 inches remain after making one revolution, you have 8 inches of travel, thus a 1:8 twist barrel.
This rifling illustration was created by Danish graphic artist Erik Dahlberg. It is published here courtesy FireArmsID.com, an excellent website for forensic firearms examiners.
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Barrel Velocity Variance
Transferable Warrnty:
Sometimes you’ll get a barrel that doesn’t stabilize bullets the way you’d anticipate, based on the stated (or presumed) twist rate. A barrel might have 1:10″ stamped on the side but it is, in truth, a 1:10.5″ twist or even a 1:9.5″. Cut-rifled barrels, such as Kriegers and Bartleins, normally hold very true to the specified twist rate. With buttoned barrels, due to the nature of the rifling process, there’s a greater chance of a small variation in twist rate. And yes, factory barrels can be slightly out of spec as well.
