Basic Gunsmithing Videos from MidwayUSA

Larry Potterfield, owner and founder of MidwayUSA, has created some basic gunsmithing videos that are worth watching. These show some key aspects of rifle metal-working, such as crowning a barrel. Be aware that these videos are really just teasers — they don’t illustrate most of the critical preparatory steps a skilled gunsmith will do, such as leveling his lathe precisely, and indicating the barrel very, very carefully. Nonetheless, there are some good, basic tips in the videos, which should be informative for all shooters, whether they do their own smithing or not. Please note that benchrest smiths may employ more advanced methods.

VIDEO One: Cutting and Crowning a Barrel (Radiused Crown)

VIDEO Two: Threading and Chambering an Octagon Barrel

VIDEO Three: Trueing the Bolt Face on a Mauser 98

Barrel “Depreciation” and the True Cost of Shooting

How much does it cost you to send a round downrange? Ask most shooters this question and they’ll start adding up the cost of components: bullets, powder, and primers. Then they’ll figure in the cost of brass, divided by the number of times the cases are reloaded.

For a 6BR shooting match bullets, match-grade primers, and 30 grains of powder, in brass reloaded a dozen times, this basic calculation gives us a cost per shot of $0.46 (forty-six cents):

Bullet $0.30 (Berger 105 VLD) MidwayUSA
Primer $0.03 (Wolf SmR magnum) Wideners
Powder $0.08 (Reloder 15 @ $18.85/lb) Powder Valley
Brass $0.05 (Lapua priced at $63/100, 12 reloads) Brunos

Total $0.46 per round

$1.00 Per Shot True Cost? Yikes!
OK, we’ve seen that it costs about $0.46 per round to shoot a 6BR. Right?

Wrong! — What if we told you that your ACTUAL cost per round might be closer to double that number? How can that be? Well… you haven’t accounted for the cost of your barrel. Every round you fire down that tube expends some of the barrel’s finite life. If, like some short-range PPC shooters, you replace barrels every 700 or 800 rounds, you need to add $0.60 to $0.70 per round for “barrel cost.” That can effectively double your cost per round, taking it well past the dollar per shot mark.

Calculating Barrel Cost Per Shot
In the table below, we calculate your barrel cost per shot, based on various expected barrel lifespans.

As noted above, a PPC barrel is typically replaced at 700-800 rounds. A 6.5-284 barrel can last 1200+ rounds, but it might need replacement after 1000 rounds or less. A 6BR barrel should give 2200-3000 rounds of accurate life, and a .308 Win barrel could remain competitive for 4,000 rounds or more.

The table below shows your barrel cost per shot, based on various “useful lives.” We assume that a barrel costs $500.00 total to replace. This includes $300.00 for the barrel itself, $160.00 for chambering/fitting, and $40.00 in 2-way shipping costs. Yes, you may have a smith that works for less, but these are typical costs shooters will encounter when ordering a rebarreling job.

The numbers are interesting. If you get 2000 rounds on your barrel instead of 1000, you save $0.25 per shot. However, extending barrel life from 2000 to 3000 rounds only saves you $0.08 per round.

NOTE: We assume component costs of $0.46 per round based on our 6BR example. If you shoot a larger caliber that burns more powder, and uses more expensive bullets and/or brass, your total cost per round will be higher.

How to Reduce Your TRUE Cost per Round
What does this tell us? First, in figuring your annual shooting budget, you need to consider the true cost per round, including barrel cost. Second, if you want to keep your true costs under control, you need to look at ways to extend your barrel life. This can be accomplished in many ways. First, you may find that switching to a different powder reduces throat erosion. Second, if you’re able to slow down your shooting pace, this can reduce barrel heat, which can extend barrel life. (A varminter in the field is well-advised to switch rifles, or switch barrels, when the barrel gets very hot from extended shot strings.) Third, modifying your cleaning methods can also extend the life of your barrel. Use solvents that reduce the need for aggressive brushing, and try to minimize the use of abrasives. Also, always use a properly fitting bore guide. Many barrels have been prematurely worn out from improper cleaning techniques.

Salt-Bath Nitriding for Barrels — Whidden is Impressed

Many shooters expend considerable time and effort to coat their bullets with friction-reducing compounds such as Boron Nitride (HBN), Molybdenum Disulfide (Moly), and Tungsten Disulfide (WS2 or ‘Danzac’). Many of these same shooters believe that coated bullets permit longer strings of fire between barrel cleanings. Also, there is some evidence that coated bullets may extend barrel life (though this remains controversial).

What if you could enjoy all the benefits of coated bullets without the effort? When you think about it, why not apply the anti-friction coating to the barrel itself, rather than the bullets? That is the thinking behind salt-bath nitriding of barrels. This nitriding process creates a very slick, very hard surface coating on the steel in the bore. The coating is only 10-20 microns thick (so it doesn’t cause pressure problems). But that coating is enough to reduce friction, and just possibly, extend useful barrel life.

John Whidden, well-known long-range shooter and 2008 Camp Perry Long-Range Champion, recently had one of his Broughton 6mm match barrels nitrided by Joel Kendrick. Joel does the salt-bath nitriding for MMI TruTec. Whidden reports he “is happy as he can be with the barrel” after the nitriding process. After nitriding, the stainless Broughton 5C barrel was “every bit as accurate as before, and noticeably easier to clean”, according to John. Also, John reports that he did NOT have to change his load after the barrel was nitrided (which left it with a handsome black, semigloss finish). Whidden says, “after cleaning, the barrel takes about 3-4 rounds to settle in… that’s the same as before.” This barrel shot very well before nitriding, and after nitriding, John used it successfully at Camp Perry in the 2009 Wimbleton Cup competition.

Overall, John tells us “Everything looks good. No accuracy loss, and easier cleaning.” He is pleased enough that he has sent more barrels to Joel Kendrick for nitride processing. John also said that he’s heard that nitrided barrels in some of the big caliber rifles, such as the .338 Lapua Magnum, are showing “significantly enhanced” barrel life.

To learn more about salt-bath nitriding for barrels, or to place a processing order with MMI-TruTec, email joelkndrck [at] aol.com, or call Joel at (704) 616-6442. Joel, a past 600-yard Shooter of the Year, is very knowledgeable about both shooting and the nitriding process. He can give you well-informed answers to your questions. Price for nitriding depends on quantity — call Joel for pricing details.

Handy Excel Formula Predicts Useful Barrel Life

How long will a barrel last before the accuracy “goes south”? There are so many variables involved (powder type, bore diameter, bullet coatings etc.) that it’s hard to predict. You might say “Well, my buddy has a .243 and he got 1500 rounds before the throat was shot out” — those kind of comparisons can be useful, but they’re not very scientific, and they won’t help much if you’ve got a gun in a new chambering (such as the 6.5×47) for which long-term test results are lacking.

Is there a more reliable way to predict barrel life — one that will work for a broad range of calibers? Well, Forum member MikeCr has developed an Excel spreadsheet that accounts for a number of variables, and gives a pretty good estimate of useful barrel life, whether you’re shooting a .223 Rem or a 338 Lapua Magnum. Mike’s program predicts barrel life using five variables: 1) Bullet Diameter; 2) Powder Charge weight; 3) Powder Heat Potential (KJ/kg); 4) Pressure (in psi); and 5) Bullet Coating (yes/no). Mike provides a table with Heat Potential ratings for most popular powder types. The user needs to know the pressure of his load. This can be estimated with QuickLOAD.

You can download the lastest version of Mike’s spreadsheet below. You’ll need Excel or an Excel viewer to open the file.

Click to Download Spreadsheet: Barrel Life Spreadsheet (Latest Version)

Shown below is Mike’s Spreadsheet, with variables for a 6BR shooting 105gr “naked” bullets with 30.3 grains of Hodgdon Varget powder. The formula predicts 2401 rounds of barrel life. That corresponds pretty well to what we’d expect for a 6BR — about 2500 rounds.

Mike observes: “There has been alot of discussion lately related to cartridge design and resulting barrel life. This is a really important factor to consider amongst a myriad of choices. Barrel life is controversial, and subjective. There are no clear-cut standards for comparison. But a few years ago, I put together a spreadsheet based on Bart Bobbit’s rule of thumb. It worked pretty good, only occasionally failing some tests when validated against posted barrel lives.

According to Ken Howell, I had to account for pressure. And Henry Child’s powder temperature testing provided another piece needed. So, I’ve tweaked it here and there to pass more tests. From 223rem to 300 UltraMagnum. Another element added, but turned off is shot interval. I would need way more tests to lock in on this. But everyone knows, the faster you shoot, the worse the barrel life.

Anyway, another factor hard to define is ‘accurate’ barrel life. This cannot be quantified without standards. Barrels are replaced when expectations are no longer met. I feel that a [barrel] passes peak potential in a finite period due to throat erosion. But that don’t mean it’s toast, if it still shoots well enough. It’s just as likely that many of us never see that peak potential anyway. It’s a slippery thing. Point-blank BR competitors will toss a barrel when it leaves the 1s. I could get another 4000 rounds from it, and be content with its performance, I’m sure.”

NOTE: Mike says: “This spreadsheet may show a lower barrel life than you prefer. But it pretty well spotlights cartridges to stay away from if you plan much time at the range or in dog town.”

Editor’s Comment: We want to stress that Mike’s spreadsheet is a helpful tool, but it is not a definitive “take-it-to-the-bank” indicator of barrel life. Mike cautions that predicting barrel life involves so many different factors (including how hot the barrel is run), that the task is a bit like predicting tread life on car tires. Still, the spreadsheet is very helpful. It can certainly put shooters on notice that some chamberings (such as the 6-284) are likely to be a barrel burners. That can help you make a smart decision when choosing a chambering for your next rifle.

TECH TIP: How to Determine Your Barrel’s Actual Twist Rate

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 heavier the bullet you will be able to stabilize.

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.

Erik Dahlberg illustration courtesy FireArmsID.com.

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.

Tony Boyer Shares Secrets in PS Interview — READ IT!

Tony Boyer is, without question, the greatest short-range Benchrest for Group shooter who has ever lived. In a rare interview for the August 2009 issue of Precision Shooting magazine, Tony shares many of his “secrets of success” with his friend (and fellow benchrester) James Mock. James also interviews Tony’s wife Faye, a superb shooter in her own right.

This Boyer interview is now, for a limited time, available online. CLICK HERE to READ INTERVIEW. Every short-range and mid-range benchrest shooter should read this article word for word, at least twice. Tony reveals insights that may surprise you, and will certainly enlighten you. You may be surprised that Tony is now shooting a .268″ neck.

And in the article Tony challenges many commonly-held ideas. For example he doesn’t think vertical is mostly load-related: “Most shooters think that vertical groups are caused by too light a powder charge. This may be true, but more often than not, the rifle has more to do with this than the load. If the rifle is muzzle heavy, this can cause vertical. Also, the way the action is set in the stock can cause vertical as can handling problems…such as shouldering the rifle.”

Barrel Quality is All-Important
What is the main secret to Benchrest accuracy? Throughout the interview, Boyer stresses the importance of barrel quality. Tony can quickly identify barrels with winning potential. He has “developed a system that takes no more than 30 rounds to determine if it is going to shoot”. Tony needs that kind of efficiency because he burns through barrels very quickly: “Contrary to what many say, I rarely shoot a barrel more than 600 rounds in competition. I can remember only one barrel that exceeded 1200 rounds.”

When asked if there was one paramount “secret” he could share to help new shooters, Tony replied: “If you have the means, buy as many barrels as possible. A great barrel is the real secret of this game. There are barrels out there that shoot better than they should. They have been given the name ‘hummer’. I can assure you that they exist.”

Shocking Video of Catastrophic Barrel Failure

In the shooting sports, safety always has to be your number one priority. Even if you have a safe load, if the barrel is obstructed in any way, such as with mud in the barrel, a squib bullet, or a bore-sighting tool left in the barrel, the barrel can blow up, pealing back like a banana skin. Serious injury or even death can result. Below is an amazing video showing a catastrophic barrel failure caused, presumably, by a barrel obstruction — probably mud or dirt. You can see the barrel blow apart, starting at time mark 0:25 seconds.

The rifle is a Browning stainless A-Bolt, caliber unknown. We don’t know for sure, but the barrel probably became obstructed when the shooter allowed the gun to rest muzzle down on the ground, so some mud collected in the bore. Below, we’ve grabbed five frames from the key section of the video. You can see the barrel split into two segments. This shooter, who was NOT wearing eye protection, was uninjured. He is is lucky that the action held and no metal shards blew backwards.

John Krieger on the Art and Science of Barrel-Making

John Krieger is widely recognized as one of the wizards of barrel-making. Krieger cut-rifled barrels are widely recognized as among the best you can buy. You’ll find Krieger barrels winning in all major disciplines, from “point-blank” benchrest to 1000-yard prone matches. John Krieger, and his staff of highly-skilled employees, are strongly committed to quality manufacturing and customer satisfaction. When asked to describe his “business philosophy”, John stated: “Everybody in the company has one concern. That’s just to make the best barrels we can make — hopefully the best barrels that have ever been made — and to try and keep (as much as humanly possible) every customer happy.”

During the NRA Annual Meeting, we had a chance to chat with John Krieger. John shared his views on a variety of technical topics, ranging from gain twist rifling, to advances in steel quality and manufacturing methods. John answered questions about barrel contours, barrel fluting, and stress relieving. John also provided some sage advice on how to protect your barrel’s crown during the cleaning process.

New, Highly Effective Bore Cleaner from Barrett

Barrett Rifles, of 50 BMG fame has released a new, high-strength non-ammonia bore cleaner that really works. We know what you’re saying… that the last thing we need is yet another “miracle” bore cleaner. However, we’ve received reliable reports from fellow shooters that Barrett’s new Heavy Bore Cleaner does an amazing job on copper. One shooter told us he had cleaned his barrel with Sweets and then followed with Barrett’s new product and a lot more fouling and copper came out. Another told us that he had to switch to a nickel-plated jag because the Barrett solvent was so effective on copper.

We don’t know the Barrett chemistry, but it does NOT contain petroleum distillates or ammonia. It IS biodegradable and non-flammable. Barrett claims: “In a two-step process, our bore cleaner first dissolves copper, then chemically binds it to the solution to remove it from the bore. It also works to remove carbon and residue and even neutralizes corrosive salts.”

We’re always skeptical when we hear about new cleaning compounds. But the reports on this product, so far, have been uniformly excellent. If you have a rifle that copper-fouls badly, you may want to check out the new Barrett Heavy Bore Cleaner. Currently it is available only in a large 16-ounce bottle that costs $24.95. Purchase from the Barrett Store or other online vendors.

Check Your Crown’s Condition with a Q-Tip

The last half-inch or so of your barrel is absolutely critical. Any damage (or abnormal wear) near the crown will cause a significant drop-off in accuracy. Here are ways you can check the end of your barrel, using a common Q-Tip.

Use Q-Tip for Barrel Inspection
To find out if you have a burr or damage to your crown, you can use an ordinary Q-tip cotton swab. Check the edges of the crown by pulling the Q-tip gently out past the edge of the crown. If you have a burr, it will “grab” the cotton and leave strands behind.

Larry Willis has another way to use a Q-Tip: “Here’s a neat trick that will surprise you with how well it works…

Just insert a Q-Tip into your barrel (like the picture below), and it will reflect enough light so that you can get a real good look at the last half inch of rifling and the crown of your barrel. In most cases you’ll find that this works much better than a flashlight. Since then, I’ve used this method about a jillion times. Q-Tips are handy to keep in your cleaning supplies anyway. This is a good way to judge approximately how well you are cleaning your barrel when you’re at the range. It’s also the best way to examine your barrel when you’re in the field.”

Larry Willis is the inventor of Innovative Technologies’ Belted Magnum Collet Resizing Die. Larry explains how this die works, and offers other reloading tips on LarryWillis.com.

Melonite Surface Treatment for Barrels, Bolts, and Actions

Ace trigger-puller Joel Kendrick, a former IBS 600-yard Shooter of the Year, has been working on a MELONITE® nitrocarburizing process for surface-hardening barrels and other gun parts. The main advantage of Melonite barrel treatment is that it reduces friction in the bore and lessens bore surface wear, potentially extending barrel life. Melonite-treatment of a bore creates a new compound layer in the top 10-20 microns of the surface, creating a very hard, slick surface. Joel has found that this surface is so slick that carbon does not easily adhere, so the barrel is easier to keep clean. Real-world tests have shown that Melonite barrel treatment definitely reduces internal barrel friction. Joel notes that, after processing, barrels deliver 50 to 100 fps LESS velocity with the same load, a reliable indicator of reduced friction. (Likewise, you’ll get less velocity when switching from naked to moly-coated bullets.) Butch Lambert has tried some Melonite-treated barrels, and he reports: “I have had Joel Kendrick do three barrels for me in Melonite. I polished them first and the finish is like a deep polished black-bluing. One Krieger has 5000 rounds on it and it is shooting just as well as when new. It has been an incredible barrel. It has no throat erosion. It has developed a bunch of pinprick looking spots in the throat, but doesn’t seem to hurt anything. The finish is so hard you can’t thread it. I have not put one of the LV barrels on yet and the heavy is a great shooter and doesn’t have many rounds on it. My experience has been great, but a more extensive test is needed.”

Salt-bath nitrocarburizing by Melonite process has been applied in a wide range of industries throughout the world for many decades. It is used to improve the wear resistance, the fatigue strength, and corrosion resistance of components made from steel, cast iron, and sintered iron materials. The Melonite process is used as an alternative to other surface engineering processes such as case hardening.

Joel tells us: “I have been experimenting with this Melonite process for the last five years. I have been testing nitrocarburized barrels on my F-class and Long Range equipment since 2005 with good results. What will it cost? Joel expects Melonite treatment will cost under $100.00 per barrel, but the final pricing structure hasn’t been set yet. There will be volume discounts for gunsmiths and manufacturers.

There are many potential applications of Melonite processing for shooters, Joel believes. In addition to barrels, bolts, actions, internal components, and even reloading equipment can be surface-hardened with the Melonite process. After processing, the surface compound layers formed consist of iron, nitrogen, carbon and oxygen. Due to its microstructure, the compound layer does not possess metallic properties. Depending on material used, the compound layer will have a Vickers hardness of about 800 to 1500 HV, and a layer depth of 10 to 20 micorons. That’s so hard that conventional reamers won’t work well on a Melonited surface, so the barrel must be chambered BEFORE Melonite processing.

Lower Friction, Less Throat Erosion, Longer Barrel Life
Joel believes there are many benefits to Melonite barrel processing. The barrels he has treated and tested have shown reduced fouling, less throat erosion, and extended useful barrel life. Melonite-treated Chrome-moly barrels will have improved corrosion resistance as well. But are there negatives? According to Joel, “with stainless barrels, Melonite processing may reduce corrosion resistance slightly. Also, the treatment process makes the surface so hard that re-chambering is not practical — so this is something you do to already-chambered barrels.”

What about accuracy? Joel says: “Melonite barrel treatment should have no effect, positive or negative, on accuracy… except to the extent that your barrel may retain its best accuracy longer since it won’t wear out as fast.”

To learn more about the Melonite nitrocarburizing process and its application to shooting products, contact Joel Kendrick, joelkndrck [at] aol.com, or call (704) 616-6442.

Bill Myers’ Indexable Rimfire Action

Virginia’s Bill Myers is recognized as one of the top rimfire smiths in the country. We featured one of his “Spec Rifles” in a recent Gun of the Week story. Built on a blue-printed Suhl 150-1 action, Bill’s Buginga-stocked benchrest rig proved to be a winner right from the start.

Bill is a creative thinker, and his own exhaustive testing has convinced him that barrel indexing can enhance accuracy in rimfire benchrest guns. Myers does acknowledge that, particularly with a very good barrel, the advantages of indexing may be subtle, and extensive testing may be required. Nonetheless, Myers believes indexing can improve rimfire accuracy.

The Challenge of Barrel Indexing
With a conventional barrel installation, employing a shoulder with a threaded tenon, it is difficult to index the barrel. Even with a cone breech that eliminates the problem of extractor cuts, you’d have to use shims to alter the barrel index position, or otherwise re-set the shoulder each time you screwed the barrel in further.

Bill has come up with a masterful solution to barrel indexing. He designed and built his own prototype custom action that clamps the barrel rather than holding it with threads. The front section of the action is sliced lengthways, and then clamped down with three bolts. A special bushing (the gold piece in photos) fits between the barrel and the action. By using bushings of different inside diameters, Bill can fit any barrel up to an inch or so diameter, so long as it has a straight contour at the breech end. To mount the barrel, Bill simply places the fitted bushing over the barrel end-shank, then slips the “sleeved” barrel into the front end of the action. Tighten three bolts, and the barrel is secure.

Indexing with the Myers’ Clamping Action
To index the barrel, Myers simply loosens the three clamping-bolts and rotates the barrel in the action. Because there is no thread to pull the barrel in or out, the headspace stays the same no matter how much the barrel is rotated. In other words you can rotate the barrel to any position on the clockface and the headspace remains unchanged.

Right now Bill has no plans to start building his own indexable rimfire actions for sale. However, he is involved in serious experimentation with barrel indexing, in cooperation with Gene Beggs and others. Over the course of the next year we may see a “semi-production” action offered that incorporates aspects of Bill Myers’ indexable, barrel-clamping receiver. For more information, contact Bill Myers, wzmyers [at] comcast.net, (540) 778-1782.