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October 30th, 2014
Can sustained rapid-fire shooting with no cool-down period wear out a quality barrel more quickly? The answer is “Yes” according to Forum member LCazador, who recently did an interesting comparison test with two .243 Win barrels. He started off with two, identical, match-grade HV taper stainless barrels. Both were NEW at the start of testing, and LCazador shot the same load through each: 95gr match bullets with 38 grains of Hodgdon Varget. After giving both barrels the same, gentle 20-round break-in, 300 rounds were then fired through each barrel — in very different ways. Barrel condition and wear were monitored with a borescope.
Barrel One — Slow Fire, Cool Down Periods, Cleaning Every 50 Rounds
At the end of the 300-round test, Barrel One looked brand new. There was none of the severe fire cracking found in Barrel Two. This barrel was shot no more than 10 times without a cool down and firing was done at a much slower pace. Cleaning for this barrel was done every 50 shots.
Barrel Two — Fast Firing, No Waiting, Cleaning Every 100 Rounds
The second barrel, which received hard use and minimal cleaning, was severely damaged with severe fire cracking at the leade and throat. As a result, the barrel had to be re-chambered. This barrel was shot 100 rounds at time without cleaning and was shot up to 20 times in succession without a cool down.
Don’t let your barrel get too hot, and keep it clean. One afternoon can ruin a barrel!
 Monitoring Barrel Wear with Borescope
Some folks worry too much about what their borescopes reveal — many barrels do not have to be “squeaky clean” to perform well. In fact some barrels run better after ten or more fouling shots. However, a borescope can be very helpful when your barrel starts losing accuracy for no apparent reason. Forum member FdShuster writes:
“A borescope is a positive way of backing up your suspicions when the rifle starts to throw an occasional (soon followed by more frequent) wild shot. Using the scope is also an excellent way to determine that the cause is barrel wear and not simply a need for a concentrated cleaning session to remove built up copper and more importantly, carbon fouling.
I’ve had a few barrels that gave every indication of being shot out. But I ‘scoped them out and found the cause to be nothing more than requiring a good cleaning. They then returned to their usual performance. There’s no guessing involved when you are able to get ‘up close and personal’ using the scope. The borescope also provides an excellent view of the all-important condition of the crown. My borescope is one of the most valuable investments I’ve ever made.”
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July 2nd, 2014
 Want to shoot better scores at your next match? Here’s a smart, inexpensive do-it-yourself project from the good folks at Criterion Barrels. For less than one dollar in materials, in just a few minutes you can create a handy, effective mirage shield, custom-fitted to your favorite rifle.
All precision shooters should be familiar with mirage, a form of optical distortion caused primarily by variations in air temperature. Savvy shooters will use mirage as a valuable tool when gauging wind speed and direction. Natural mirage is unavoidable, but there are many techniques designed to limit its influence in long-range marksmanship.
A form of mirage can be produced by the barrel itself. Heat rising from the barrel may distort sight picture through your optics, leading to erratic results. Mirage caused by barrel heat can be reduced dramatically by a simple, light-weight mirage shield.
How to Make a Mirage Shield
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A mirage shield is an extremely cost-effective way to eliminate a commonly-encountered problem. Making your own mirage shield is easy. Using old venetian blind strips and common household materials and tools, you can construct your own mirage shield for under one dollar. |
Materials Required:
1. Vertical PVC Venetian blind panel
2. Three 1”x1” pieces adhesive-backed Velcro
3. Ruler or tape measure
4. Scissors or box cutter
5. Pencil or marker |
1. Measure the distance from the end of the receiver or rail to the crown of the barrel.
2. Using a pencil and ruler, measure the same distance and mark an even line across the blind.
3. Cut across the line using scissors or a box cutter, shortening the blind to the required length. (Remember, measure twice, cut once!)
4. Expose the adhesive backing on the loop side of the Velcro. Center and apply the Velcro strips on the barrel at regular intervals.
5. Expose the adhesive backing of the fuzzy side of the Velcro.
6. Place the blind on the upper side of the barrel. Apply downward pressure. Once the Velcro has secured itself to the barrel, separate the two sides. Proceed to mold both sides of the Velcro to fit the contour of their respective surfaces.
7. Reaffix the blind. Barrel related mirage is now a thing of the past!
How to Remove and Re-Attach the Mirage Shield
Removal of your mirage shield is accomplished by simply removing the blind. You can un-install the Velcro by pulling off the strips and then gently removing any adhesive residue left behind using an appropriate solvent. (Simple cooking oil may do the job.) Caution: With fine, high-polish blued barrels, test any solvent on a non-visible section of the barrel. Before storing the gun, re-oil the barrel to remove active solvents and residual fingerprints.
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October 2nd, 2013
Less weight plus better heat dissipation — Sound good? Here is an innovative barrel technology that promises worthwhile performance benefits for hunters or match shooters. Lothar Walther (LW) has developed a new bi-metal barrel system that cuts weight dramatically while promising significantly-enhanced heat dissipation.
Walther’s Ultra-Lightweight Barrels combine steel with lightweight alloys. This results in a significant weight reduction without the use of carbon fiber, epoxy binders, or other heat-retaining materials. Beginning as an LW50 stainless blank, the barrel is precision-machined to remove excess weight. An outer casing of light-weight alloys is machined and the two are fitted together without adhesives. Basically you end up with the steel inner barrel inside a larger-diameter fluted aluminum outer barrel (see diagram). This gives you the ‘best of both worlds’ — light weight for ease of carry, and thick diameter for rigidity and enhanced heat dissipation. Near the action, the barrel remains all-steel.
The barrels come pre-chambered in your choice of caliber/cartridge, from .22LR up to .338 Lapua Magnum. Walther chambers the barrel — but a gunsmith is still required to finish the shoulder so that the headspace is set correctly for your action. These barrels are not inexpensive. A typical bi-metal Walther Barrel runs $850.00 – $875.00, for barrel lengths from 22″ to 30″. Threading for a muzzle brake or suppressor (if desired) is normally included in that price.
 We haven’t tested one of these bi-metal composite barrels, but the potential for significant weight savings is obvious — aluminum is a lot lighter than steel. What’s more, a metals expert we contacted said that a bi-metal system employing fluted aluminum over steel, if assembled properly, could dissipate heat much better than steel alone (given the same diameter). Stainless steel has a thermal conductivity factor of 16. Aluminum has a thermal conductivity factor of 250.*
Our expert also pointed out that some other composite barrel systems on the market actually increase heat retention because they place insulating materials next to the inner steel barrel. (Carbon, Fiberglass, and Epoxy are all considered “insulating substances” as they have very low thermal conductivity*.) The LW system of aluminum over metal should avoid this mistake, our expert believes. Lothar Walther says: “Unlike solid steel barrels, this barrel sheds heat fast. VERY FAST!”
Half the Weight of Conventional Barrels
How much weight can you save? With a 1.200″ shank diameter and a muzzle diameter of 0.850″, the LW Ultra-Lightweight Barrel is less than half the weight of a standard varmint barrel of the same size. Walther claims its UltraLight Barrel can be “carried for long distances and stand up to heavy firing.” This, LW says, makes these barrels “perfect… for varmint and tactical uses”.
Pre-Chambered Ultra-Lightweight Barrels Available in .22 to .338 Calibers
Lothar Walther offers Ultra-Lightweight barrels in a full range of calibers from .22LR to .338. Each Ultra-Lightweight Barrel comes complete with chamber, crown, and breech threads. These barrels are fluted by the factory. If you order a LW Ultra-Lightweight barrel, Lothar Walter provides the services of a specialist trained in building guns with these barrels. To order one of Lothar Walther’s bi-metal barrels, CLICK HERE or contact Lothar Walthar at the address below:
Lothar Walther Precision Tools, Inc.
3425 Hutchinson Rd. – Cumming, GA 30040
Phone: 770-889-9998 | Fax: 770-889-4919
E-Mail: lotharwalther [at] mindspring.com
Website: www.lothar-walther.com
*Thermal conductivity is the quantity of heat transmitted through a unit thickness in a direction normal to a surface of unit area, due to a unit temperature gradient under steady state conditions. The factor values are based on this formula: W/(m.K) = 0.85984 kcal/(hr.m. °C). Here are thermal conductivty values for common materials: Aluminum, 250; Brass, 109; Steel (Carbon 1%), 45; Stainless Steel, 16; Carbon, 1.7; Brick dense, 1.3; Concrete (medium) 0.7; Epoxy, 0.35; Fiberglass, .04.
Story tip from EdLongRange. We welcome reader submissions.
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June 10th, 2012
It’s vitally important to keep your ammo at “normal” temps during the hot summer months. Even if you use “temp-insensitive” powders, studies suggest that pressures can still rise dramatically when the entire cartridge gets hot, possibly because of primer heating. It’s smart to keep your loaded ammo in an insulated storage unit, possibly with a Blue Ice Cool Pak if you expect it to get quite hot. Don’t leave your ammo in the car or truck — temps can exceed 140° in a vehicle parked in the sun.
 Insulated Case Does Double-Duty
Standard plastic coolers work fine, but if you don’t want to borrow the family’s food carriers, consider this Norchill insulated Cooler Bag. When not used to keep your ammo cool, the 7″ wide x 12″ high x 14″ long small Norchill Bag doubles as a gear carrier. Norchill bags feature dual-temp insulation and a waterproof inner liner. With side-zip compartments, Norchill Cooler Bags are more versatile than typical plastic coolers. These Norchill cooler bags are soft, collapsible and can be rolled up to fit into your carry on luggage. When not in use for ammo, they can be used to as a suitcase, or carry bag for cameras, optics, and electronic gear.
Norchill Bags come in three sizes and a variety of colors. Price starts at $39.99 for the small bag (12-can capacity) is $39.99. The 10″x12″x18″ medium bag has double the capacity (24 cans) and costs $49.99. There is also a jumbo 48-can capacity bag, 13″x13″x21″. But this is probably more capacity than you’d ever need.
 To learn more about how ambient temperature (and primer choice) affect pressures (and hence velocities) you should read the article Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author uses a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.
For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per F° for the Varget load. If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.” |
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October 18th, 2010
Monitor Barrel Heat with Pocket InfraRed Gauges
You never want to run the barrel of a precision rifle too hot. Excessive barrel heat kills accuracy, increases copper fouling, and can cause rapid barrel throat wear. Over the years people have devised various means to cool their barrels — from electric fans to dunking in tubs of ice water.
 But how do you know if your barrel is too hot? Consider a “non-contact” thermometer that reads your barrel’s “infrared signature”. The Kintrex or Actron pocket-sized, non-contact IR thermometers are ideal for shooters at the range or in the prairie dog fields. Both are handy and inexpensive — costing about twenty bucks (on sale).
Pen-Sized Kintrex
Just 3.2″ long, and weighing a mere 1.3 ounces, the waterproof Kintrex IRT0401 (IP67) is small enough to carry in your pocket, and will easily stow in any range bag/box. The unit measures from -67 to 428 °F (-55 to 220 °C). Kintrex is a respected manufacturer that also makes larger hand-held IR thermometers for industrial and shop applications. Priced at just $21.11 on Amazon.com, the tiny Kintrex is one gadget that every serious shooter should have. Given the cost of replacing barrels these days, can you afford NOT to have a temp gauge for your match or varmint barrel?
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Actron PocketTherm for just $18.22
The compact Actron CP7875 PocketTherm Infrared Thermometer is on sale right now on Amazon.com for just $18.22. Roughly 4″ x 1.5″ in size, it is slightly larger than the Kintrex, but still small enough to carry in a pocket. It features an angled head and may be easier to hold than the Kintrex for some users. It works instantly with intuitive one-button operation, measuring temp ranges from -27º to 428º F (-33º to 220º C). Rated battery life is 20-25 hours. The backlit display is easy to read. However, you need to place the Actron PocketTherm close to the “target”. Most larger “industrial” spot thermometers (both laser and infrared), have beam ratios from 6:1 to 10:1, allowing them to measure a 1″ circle at 6″-10″. The CP7875 has a 1:1 ratio, so it measures a 10″ circle at 10″ distance. To get an accurate temp on a barrel, you must hold the thermometer within an inch or so. That’s not a big deal when measuring barrel heat, but the beam ratio may limit the usefulness of the PocketTherm for other tasks.
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January 4th, 2010
You never want to run the barrel of a precision rifle too hot. Excessive barrel heat kills accuracy, increases copper fouling, and can cause rapid barrel throat wear. Over the years people have devised various means to cool their barrels — from electric fans to dunking in tubs of ice water.
But how do you know if your barrel is too hot? Consider a “non-contact” thermometer that reads your barrel’s “infrared signature”. The $20.00 Kintrex pocket-sized, non-contact IR thermometer is ideal for shooters at the range or in the prairie dog fields.
Just 3.2″ long, and weighing a mere 1.3 ounces, the waterproof Kintrex IRT0401 (IP67) is small enough to carry in your pocket, and will easily stow in any range bag/box. The unit measures from -67 to 428 °F (-55 to 220 °C). Given the low cost and compact size, we highly recommend you get one of these units.
KINTREX IRT0401 Compact Waterproof (IP67) Infrared Thermometer
Kintrex is a respected manufacturer that also makes larger hand-held IR thermometers for industrial and shop applications. Priced at just $19.95 on Amazon.com, the tiny Kintrex is one new gadget that every serious shooter should have. Given the cost of replacing barrels these days, can you afford NOT to have a good temp gauge for your match or varmint barrel?
If you have more room in your range kit, and want a larger unit with longer battery life for daily shop duty, we recommend the Kintrex IRT0421. A top-selling tool, this $47.08 unit has a full-sized pistol grip and features laser targeting for ultra-precise temp-gauging. It records temps from -76 °F all the way up to 932 °F (-60 to 500 °C). Black & Decker also offers the versatile TLD100 IR thermometer, which can be used for thermal leak detection in the home as well.
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