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November 20th, 2012
 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 ten times, this basic calculation gives us a cost per shot of $0.51 (fifty-one cents):
Bullet $0.33 (Berger 105 VLD) Grafs.com
Primer $0.02 (Tula/Wolf SmR magnum) PVI
Powder $0.08 (Reloder 15 @ $19.15/lb) PVI
Brass $0.08 (Lapua @ $82.30/100, 10 reloads)
Total = $0.51 per round
NOTE: 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 than $0.51.
$1.00 Per Shot True Cost? Yikes!
OK, we’ve seen that it costs about $0.51 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 2000-2600 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 custom barrel costs $540.00 total to replace. This includes $300.00 for the barrel itself, $200.00 for chambering/fitting (conservative number), and $40.00 in 2-way shipping costs. 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 $0.27 per shot. However, extending barrel life from 2000 to 3000 rounds only saves you $0.09 per round. The longer you keep your barrel the more you save, but the savings per shot decreases as the round count increases.
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 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.
October 23rd, 2012
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, 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.
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).
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, 6BR, .243 Win, 6.5×47 Lapua, 6.5×55, .308 Win, 30-06, or 300 WM 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. When you complete a new 6BR rifle, it’s wise 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.
August 30th, 2012
Even if you don’t shoot competitively, you can benefit from having a mirage shield on your barrel. The shield helps prevent barrel heat from “cooking” the air in front of your scope, which can distort the view you see through the optic. Barrel heat creates a mirage effect that can blur the target image and actually shift your apparent aiming point up and down. Competitors know that a mirage shield helps them shoot smaller groups and better scores. Mirage shields can likewise benefit Varmint shooters on those hot summer groundhog and prairie dog expeditions.
Make a Mirage Shield from Discarded X-Ray Film
Forum member Fabian from Germany, whose Sako 6BR was featured as a Gun of the Week, has devised a clever and inexpensive mirage band option. Fabian is a radiologist by trade. He notes that many X-ray machines require a daily test film for calibration. These are normally just discarded in the trash, so you can get them for free.
Fabian explains: “I’m a radiologist, so I handle medical x-ray films every day. Modern X-ray machines use laser-based printers and they need to print a test-film every day. One x-ray film is about 43×35 cm (16.9″ x 13.7″). Made from polyester, the films are very stable and only 0.007″ inches thick. They are light-weight, semi-transparent, and very stable. Using normal scissors, you can easily cut four mirage shields from a single sheet of film. Then glue on some velcro to attach to your barrel. Try it, you will not be disappointed.”
More Do-It-Yourself Ideas
Other forum members have made mirage shields out of common, inexpensive materials such as old venetian blinds, thin plastic edging strips, and even cardboard reinforced with strapping tape. There’s no “magic material”. However many shooters have found that wider shields (extending well past the barrel sides) work better than narrow shields, particularly in hot weather.
Mirage Shields with Printed Designs
If you prefer to purchase a mirage shield, Shotmaster 10X offers a wide variety of shields starting at just $5.00 for a plain white 18″ shield. Patterned shields (including camo designs) are priced by length: $8.50 (18″), $9.50 (20″), $11.00 (24″). All Shotmaster shields come with two (2) velcro patches with self-stick adhesive.
July 27th, 2012
 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.
June 5th, 2012
Scientists at the Oak Ridge National Laboratory (ORNL) have developed a system that uses lasers and fiber optics to measure very small changes (deflections) in a rifle barrel. These deflections are recorded with laser sensors, and then algorithms are used to compute the resultant changes in bullet trajectory. Using computer-calculated trajectories, the digital sighting system’s “virtual” reticle automatically adjusts to compensate for barrel deflection, as well as changing environmental conditions. The microprocessor-controlled digital reticle can adjust to 1/1000th of a Minute of Angle (MOA). That makes it far more precise than any conventional riflescope reticle.
ORNL Barrel Sensor with Compensating Reticle
Shown below is a laboratory prototype of Oak Ridge National Laboratory’s Reticle Compensating Rifle Barrel Reference Sensor. This system precisely measures the deflection of the barrel relative to the sight and then electronically makes the necessary corrections. The system was developed by a team led by Oak Ridge National Laboratory’s Slobodan Rajic, shown in the photo.
 The Reticle Compensating Rifle Barrel Reference Sensor takes the guesswork out of shooting by shifting the burden of knowing the relative position between the barrel and the weapon sight axes from the shooter to an electronic sensor. The system precisely measures the deflection of the barrel relative to the sight and then electronically realigns the moving reticle, or crosshairs, with the true position of the barrel, or bore axis.
“When a weapon is sighted in, the aim point and bullet point of impact coincide,” Rajic said. “However, in the field, anything that comes into contact with the barrel can cause perturbation of the barrel and induce errors.”
With modern high-caliber rifles boasting ranges of up to two miles, even very small barrel disruptions can cause a shooter to miss by a wide margin. That makes this technology indispensable from a marksman’s perspective, Rajic said.
From a technological standpoint, the approach is straightforward. ORNL starts with fluted barrels (the flutes play a key role). With the ORNL technology, glass optical fibers are placed into the flutes. The sensor system contains a laser diode that sends a signal beam into the optical fibers parallel to the bore axis of the barrel.
“The optical fibers are designed to split the laser beam twice, sending one beam along the top of the rifle barrel and another light beam along the side of the barrel,” Rajic said. “Thus, we can measure both the vertical and horizontal barrel deflection.”
Through a combination of algorithms, optics and additional sensor inputs, the system can take into account distance and other factors affecting the bullet trajectory. Ultimately, the whole optical/laser/digital system provides the shooter with crosshairs that automatically adjust for conditions in real time.
A Compensating Reticle with 1/1000 MOA Precision
Skeptics of electronic sighting systems have complained that the resolution of a digital rifle-sight is too crude to allow precise aiming. There simply aren’t enough pixels on a viewscreen to allow ultra-precise aiming at long-range targets, shooters have said. In fairness, the existing commercially-available digital rifle sighting systems HAVE been crude — with a lo-rez screens like you might find in a portable GPS.
Well you can forget all that. ORCL has achieved a break-through in digital sighting. The bar has been raised — by an order of magnitude. The resolution of ORNL’s digital, sensor-informed Compensating Reticle is 125 times better than that of traditional target reticles, which can normally be adjusted by one-eighth Minute of Angle (MOA) (at best). Now get this — the ORNL sensor can sense angular displacement and shift the reticle by 1/1,000th of a minute of angle. While this system is expensive, and designed (at this point) for the military, this technology could eventually benefit sport shooters. A decade from now, we would not be surprised if long-range civilian shooters commonly use electronically-enhanced optics, with digital reticles that automatically compensate for bullet drop (and maybe even windage).
ORNL scientists are also working on technology that could yield much more precise and accurate plots of bullet trajectories. We will no longer have to rely on “guesstimated” data inputs, and certain assumptions about bullet drag factors. Rajic and colleagues are developing a laser-based, bullet tracking system that would record plot the bullet’s actual flight path while the bullet is in the air. In other words, this tracking system would be able to plot the bullet’s true trajectory from muzzle to target. That is much differerent than current ballistic “solvers” which merely draw a predicted arc based on muzzle velocity, wind and temp inputs, and a reference BC value.
Oak Ridge National Laboratory is a multi-program science and technology laboratory managed for the U.S. Department of Energy by UT-Battelle, LLC. Over 3000 scientists and engineers at ORNL conduct basic and applied research and development to create scientific knowledge and new technology in key areas of science, energy, the environment, and national security.
May 10th, 2012
NOTE: This article was released in May 2012. That is over TEN YEARS AGO. The items are no longer offered with such pricing.
M1 Garand barreled receivers (item RM1SABRWB) are now available from the CMP for $350.00 plus $12.95 shipping. Combine one of these with an $82.00 walnut M1 Garand replacement stock from Boyds’ Gunstocks and you’ll have a handsome and affordable rig. (But sights, trigger group, op rod, gas system, and other key components must still be acquired.) These are Grade B receivers with “service grade” or “high quality service grade” barrels. The CMP notes that: “Receiver may have minor pitting / frosting above and below below the wood line and has been refinished. Bolt includes: extractor, extractor spring & plunger, ejector, ejector spring and firing pin.”
March 15th, 2012
Get ready for the 7th Annual Shilen Swap Meet. Rain or shine, the Swap Meet will be held from 8:00 am to 3:00 pm on Saturday, April 7th, in the Shilen parking lot (Ennis, TX). The event is open to “all comers” — both buyers and sellers. There are NO fees or costs. Anyone can set up a table or just back their truck up and drop their tailgate. There will be gun stuff everywhere — buy and sell as much as you like. And there will be FREE FOOD — complementary chili, frito pie, water, tea, or coffee.
Shilen does request advanced notice from Swap meet attendees, especially folks selling shooting gear: “Please call (972) 875-5318 if you plan on attending so we can have a rough head count. If you want to put up a table please call, fax or email us and let us know. We will add you to the list of vendors.”
Big Discounts on Barrels
Shilen’s ‘Swap Meet Barrels’ will be BACK. These are first-quality barrels built for customers who requested a specific contour, twist rate, or caliber, but later changed their minds. Shilen let these customers modify their orders, but some of these custom-ordered barrels remain in inventory. These pre-ordered “orphan” barrels will be sold at deeply discounted prices at the Swap Meet. NOTE: All warranties still apply; these are NOT lower quality or factory seconds.
Factory tours will be given. During the morning tours, the drill, ream and rifle machine will be operating. Schedule so far is that factory tours (with RUNNING machines) will be offered at 8:00 am, 8:30 am, 9:00 am, 9:30 am, 10:00 am, 10:30 am, 11:00 am and 11:30 am. Tours will continue in the afternoon, but no machines will run then.
February 24th, 2012
 Larry Racine is a respected gunsmith based in New Hampshire. He is also a two-time member of the U.S. Palma Team, and a five-time New Hampshire State Highpower rifle champion. Larry, who runs LPR Gunsmithing, has developed a brilliantly simple means of switching rifle barrels with an ordinary spanner or open-end wrench. With this set-up you can switch barrels in the field in seconds without the need for a barrel vice.
For most barrels, Larry mills a hex with six flats on the end of the barrel. This allows a shooter to change barrels quickly at home or on the line with a simple box-head wrench or a socket wrench. Larry says: “You don’t even have to take the barreled action out of the gun. Just set the buttstock on the ground, between your feet, put a wrench on it, hit it with the palm of your hand — and off comes the barrel.” For barrels fitted with a muzzle brake, Larry has a slightly different system. He mills two flats behind the brake so you can use an open-end wrench to do the job.
With either a hex on the end, or two flats for a brake-equipped rifle, the system works with any medium- to heavy-contour barrel with a muzzle-diameter of at least 0.700″. This will even work for high-power rigs using clamp-on sights or bloop tubes. Larry explains: “A lot of us here in New England use clamp-on front sights. The barrel will be turned to 0.750 for the sight, with the hex on the end. A bloop tube can go right over the end, no problem.”
Larry has used this system over the past few years to win a number of matches. In one 600-yard 3 by 20 prone match, Larry used three different barrels, with three different chamberings, on the same Savage rifle. Larry changed the barrels on the line.
Larry was able to do this because the system has little to no loss of zero from one installation of a given barrel to the next installation of that barrel. This lets the shooter start the match with confidence that the first sighter will be on paper. Larry reports that the simple system works great: “To date we have used this system on Savage, Remington, Winchester, RPA, and Nesika actions.”
Racine’s system is very affordable. If Larry does the chamber work on your barrel he charges $45.00 extra to mill a hex or two flats on your barrel. If you only want the hex or flats done, Larry charges $55.00. For more info, visit LPRGunsmith.com or call Larry at (603) 357-0055.
January 5th, 2012
 Magnum Research has released a new semi-auto .22LR rifle, the MLR22AT, that should be good for plinking, walk-around varminting, and rimfire gun games. MSRP for the MLR22AT will be $562. The rifles will start shipping in spring 2012.
The MLR22AT features a .22LR Benz target chamber optimized for semi-automatics. The black anodized receiver is CNC-machined from a 6061-T6 aluminum forging. The MLR22AT has an approximate weight of 4 ¼ lbs, barrel length of 17 inches, and OAL of 35.5 inches. This rifle utilizes the 10/22 trigger group and Ruger 10/22 rotary magazines — that means you have a wide choice of aftermarket upgrades.
The MLR22AT features a lightweight, ambidextrous thumbhole tupperware (polypropylene) stock. The stock material incorporates fiber stiffeners, but we still bet this stock is too flexy. Magnum Research claims the comb is high enough to shoot with optics. We just wish the fore-end was stiffer and came with a sling swivel stud for mounting a Harris bipod. Then this compact rifle would be good for rimfire tactical matches as well.
Graphite-Sleeved Barrel is Light, Stiff, and Runs Cool
The most trick feature on this rifle is the graphite-sleeved bull barrel, a Magnum Research exclusive. The barrel’s patented uni-directional graphite fibers, parallel to the bore axis, produce a lightweight barrel with exceptional stiffness. (Magnum Research claims the barrel has six times the stiffness of steel.) The graphite construction definitely saves weight — this barrel tips the scales at just 13-16 ounces, depending on barrel length. Magnum Research also claims the composite barrel dissipates heat up to 43% faster than steel. Sounds good, but heat isn’t as much of an issue with rimfire barrels, as compared to centerfire tubes.
September 16th, 2011
Here’s a little known fact that may startle most readers, even experienced gunsmiths: your barrel wears out in a matter of seconds. The useful life of a typical match barrel, in terms of actual bullet-in-barrel time, is only a few seconds. How can that be, you ask? Well you need to look at the actual time that bullets spend traveling through the bore during the barrel’s useful life. (Hint: it’s not very long).
Bullet-Time-in-Barrel Calculations
If a bullet flies at 3000 fps, it will pass through a 24″ (two-foot) barrel in 1/1500th of a second. If you have a useful barrel life of 3000 rounds, that would translate to just two seconds of actual bullet-in-barrel operating time.
Ah, but it’s not that simple. Your bullet starts at zero velocity and then accelerates as it passes through the bore, so the projectile’s average velocity is not the same as the 3000 fps muzzle velocity. So how long does a centerfire bullet (with 3000 fps MV) typically stay in the bore? The answer is about .002 seconds. This number was calculated by Varmint Al, who is a really smart engineer dude who worked at the Lawrence Livermore Laboratory, a government think tank that develops neutron bombs, fusion reactors and other simple stuff.
On his Barrel Tuner page, Varmint Al figured out that the amount of time a bullet spends in a barrel during firing is under .002 seconds. Al writes: “The approximate time that it takes a 3300 fps muzzle velocity bullet to exit the barrel, assuming a constant acceleration, is 0.0011 seconds. Actual exit times would be longer since the bullet is not under constant acceleration.”
We’ll use the .002 number for our calculations here, knowing that the exact number depends on barrel length and muzzle velocity. But .002 is a good average that errs, if anything, on the side of more barrel operating life rather than less.
So, if a bullet spends .002 seconds in the barrel during each shot, and you get 3000 rounds of accurate barrel life, how much actual firing time does the barrel deliver before it loses accuracy? That’s simple math: 3000 x .002 seconds = 6 seconds.
 Gone in Six Seconds. Want to Cry Now?
Six seconds. That’s how long your barrel actually functions (in terms of bullet-in-barrel shot time) before it “goes south.” Yes, we know some barrels last longer than 3000 rounds. On the other hand, plenty of .243 Win and 6.5-284 barrels lose accuracy in 1500 rounds or less. If your barrel loses accuracy at the 1500-round mark, then it only worked for three seconds! Of course, if you are shooting a “long-lived” .308 Win that goes 5000 rounds before losing accuracy, then you get a whopping TEN seconds of barrel life. Anyway you look at it, a rifle barrel has very little longevity, when you consider actual firing time.
People already lament the high cost of replacing barrels. Now that you know how short-lived barrels really are, you can complain even louder. Of course our analysis does give you even more of an excuse to buy a nice new Bartlein, Krieger, Shilen etc. barrel for that fine rifle of yours.
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