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August 24th, 2013
 One of the easiest ways to build a portable target stand is to use PVC pipe and connectors. Utah .308 Shooter “Cheese” has created a simple yet sturdy target frame, and he’s shared his design so you can build a similar frame easily and at low cost. The components are wood furring strips, 2″-diameter PVC pipes (and connections), and a 2’x3′ sheet of cardboard. The PVC base can be glued together, or, for easier transport and storage, you can leave some or all of the connections free. “Cheese” tells us: “I didn’t glue any of it together so I could disassemble it, shove it in a bag and take it anywhere.”
“All the parts are just pushed together and not glued. That way I can break it down and carry it all in a bag. Also, if a buddy (not me!) happens to shoot the stand, I can easily replace just the damaged piece. The last 6 inches of the furring strips are wittled-down a bit so they can be pushed into the upright pipes with a little friction. The cardboard is 2 x 3 feet, and I use a staple gun to attach it to the furring strips. Then I just staple the target onto the cardboard and go at it.
Of course you can modify the dimensions as desired. I chose the black ABS pipe over white PVC simply for cost — black ABS is a little cheaper. You can also glue some or all of the parts together, it’ll just be larger for transporting. In windy conditions, the thing likes to come apart. Duct tape might work well.
For weight, I thought about filling the two end pipes with sand and gluing test caps on each of their ends. The test caps still allow the pipes to slip into the elbows.”
Add Anchors or Internal Weight for Stability
On a very windy day, a PVC stand can shake or even topple over. There are a couple solutions to this. Some people fill the PVC pipe sections with sand to add weight, or you can put short sections of Re-BAR inside the long legs. One GlockTalk forum member noted: “I built [a frame] almost identical to this. I also take four pieces of wire coathanger bent into an inverted “U” shape to anchor the frame to the ground. It is so light that wind will knock the stand over [without anchors].”
Assembly Diagram with Dimensions
The photo below shows all the components of the base, with dimensions. The overall maximum assembled dimensions are roughly 26″ wide, 41″ deep, and 66″ tall (the cardboard is 2 x 3 ft).
You can find photos of a similar home-made PVC target stand (with a slightly different rear section) on the Box of Truth website. This also employs a PVC tubing base with wood uprights. We’ve also seen all-PVC target stands, but we’ve found that it is easier to attach the cardboard to wood strips than to PVC pipe. Also, if the upper section is wood, you can fit different height targets, while using the same base.
August 22nd, 2013
 Building your own portable shooting bench is a great do-it-yourself project. You can build a sturdy bench for well under $100 in materials. Compare that to some deluxe factory-built benches which may cost $500.00 or more.
FREE Bench Plans on the Web
You’ll find a wide assortment of home-built shooting bench designs (both portable and fixed) on the internet. Renovation Headquarters has links to FREE Plans and building instructions for fourteen (14) different shooting benches. There are all-wood shooting bench designs as well as benches that combine a wood top with a metal sub-frame or legs.
CLICK HERE for Shooting Bench FREE Plans Webpage
Among Renovation HQ’s fourteen featured shooting benches, here are five designs we liked:
Reader Jim Jewell has used the eHow bench design shown above. He recommends it highly. Jim reports: “A colleague and I built two of the eHow permanent wood, sturdy benches for our Pt. Phillips Rod and Gun Club in PA, which had outdated benches. I want to tell you that these benches are very stable and a real bargain. The benches cost precisely $100.00 each using the bill of materials and pressure treated wood. The bill of materials, with careful cutting, using a Chop saw, resulted in almost no scrap wood if carefully measured and cut. The plans are terrific and the benches are great platforms for bench-rest shooting. I made only one modification — I left a 6″ wing on both sides of the table to mount a spotting scope. Further we added a base of dry QuickCrete or similar fast setting concrete mix material. Add it dry, make sure the table is level and fill in the 6″ hole. The hole and QuickCrete add maximum stability. The QuickCrete sucks moisture from the ground, hardens in situ, and adds stability to the bench.
I can’t recommend this design highly enough. It is dirt cheap for clubs on a budget, goes together quickly, the table is very stable and there is no waste if you make precise measurements and cuts. A bag of QuickCrete is enough for two tables adding about $2.00 to the cost of each table. We plan on building new tables for the whole club for under $1000. After about a year, with a completely water-free wood in the bench I recommend a coat of Thompson’s Water Seal and these benches should last a long time.”
Heavy Wood Bench That Converts to Three Sections for Transport
In addition to the fourteen benches mentioned above, here is an interesting break-down bench design. Call it a “semi-portable” bench. The legs and frame are made from stout 4×4 post segments so the bench is fairly heavy. However, this bench can break down into three (3) sections for easier transport to and from the range. Dado-cut channels assure proper top alignment. This might be a good choice if you plan a multi-day excursion to a location without fixed benches. This three-leg bench design can be made from easy-to-locate materials. Note: The dimensions of this bench are are larger than typical fixed benches to accommodate 50 BMGs and other big rifles. CLICK HERE for more details.
Do you like the bench in the illustration at the beginning of this story (top right)? This is a prototype design by Chris Byrne of the Anarchangel Blog. For more details, CLICK HERE.
August 21st, 2013
If you have a match, hunting, or tactical rifle that needs a little more “stiction” in the grip or fore-arm areas, particularly in wet or humid conditions, consider adding a non-slip coating to the stock. This is easily done with inexpensive materials. R+D Precision has a simple do-it-yourself procedure for adding texture to your stock. Be forewarned — this is basically a permanent addition to your stock, so you might want to practice first. Also the application of the bedding compound will change the color of the stock, so you may want to re-finish the stock.
Marking the Area to Texture with Steel-Bed or Similar Material
Tape off the area you want to put the texture. Spread a very thin coat of the Steel-Bed on the stock, just enough to cover the area. This can be done using Marine-Tex or Steel-Bed. Other products could be used but Steel-Bed is proven, and it’s what R+D prefers for the job.
Best Method for Applying Texture
Here is the secret to adding texture: Using the tongue depressor that is in the kit or something similar, BOUNCE the flat part of the stick on the still-wet bedding to get the textured effect. Once the bedding has dried for about an hour, and still kind of tacky, remove the tape, pulling at a sharp angle to leave a nice sharp edge. If the bedding has a sharp raised area where the tape was, wet your finger and rub along the edge and it will knock off the edge but still give that nice sharp transition.
Click HERE for more photos.
August 20th, 2013
Burris Signature Rings with polymer inserts are an excellent product. The inserts allow you to clamp your scope securely without ring marks. Moreover, using the matched offset inserts you can “pre-load” your scope to add additional elevation. This helps keep the scope centered in its elevation range while shooting at long range. Additionally, with a -20 insert set in the front and a +20 insert set in the rear, you may be able to zero at very long ranges without using an angled scope base — and that can save money. (To move your point of impact upwards, you lower the front of the scope relative to the bore axis, while raising the rear of the scope.)
Insert Elevation Values and Ring Spacing
People are sometimes confused when they employ the Burris inserts. The inset numbers (-10, +10, -20, +20 etc.) refer to hundredths of inch shim values, rather than to MOA. And you need the correct, matched top/bottom pair of inserts to give you the marked thousandth value. Importantly, the actual amount of elevation you get with Burris inserts will depend BOTH on the insert value AND the spacing between ring centers.
Forum member Gunamonth has explained this in our Shooters’ Forum:
Burris inserts are [marked] in thousandths of an inch, not MOA. To know how many MOA you gain you also need to know the ring spacing. For example, with a -20 thou insert set in the front and a +20 thou insert set in the rear, if the ring spacing is 6″, the elevation change will be approximately +24 MOA upwards.
Here’s how we calculate that. If you have a 2 X 0.020″ “lift” over a distance of 6 inches (i.e. 0.040″ total offset at 0.5 feet) that’s equivalent to 0.080″ “lift” over 12 inches (one foot). There are 300 feet in 100 yards so we multiply 0.080″ X 300 and get 24″ for the total elevation increase at 100 yard. (Note: One inch at 100 yards isn’t exactly a MOA but it’s fairly close.)
Here’s a formula, with all units in inches:
Total Ring Offset
——————– X 3600 = Change @ 100 yards
Ring Spacing
(.020 + .020)
—————– X 3600 = 24 inches at 100 yards
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NOTE: Using the above formula, the only time the marked insert offset will equal the actual MOA shift is when the center to center ring spacing is 3.60″. Of course, you are not required to use 3.60″ spacing, but if you have a different spacing your elevation “lift” will be more or less than the values on the inserts.
July 2nd, 2013
 Many parts of the country are experiencing a heat wave right now. It was 117° F in Las Vegas yesterday. Unfortunately, this is “prime time” for shooting matches, so competitors may have no choice but to shoot in very hot weather. When ambient temperatures soar into the 100s, you need to be especially careful about barrel heat. Bad things can happen if your barrel gets too hot. First, with some barrels, the point of impact (POI) will shift or “walk” as the barrel heats up excessively. Second, even if the POI doesn’t change, the groups can open up dramatically when the barrel gets too hot. Third, if the barrel is very hot, the chamber will transfer heat to your loaded cartridge, which can lead to pressure issues. Finally, hot barrels wear out faster. This is a very real concern, particularly for varmint shooters who may shoot hundreds of rounds in a day. For this reason, many varminters switch among various guns, never letting a particular barrel get too hot.
How do you monitor your barrel temperature other than guessing by “feel”? BAR-L Benchrest strips visually display heat readings from 86 to 140 degrees F. Think of these strips as compact, unbreakable thermometers. These adhesive-backed strips can be used to monitor barrel heating. Put a strip on the side of the barrel and the barrel’s temp will be indicated by a stripe that changes from black to green. These strips are easy to read. The green box displays the current temperature of the barrel in both °F and °C. We recommend using the Benchrest strip (86F to 140F), shown in the middle. There is also a “General Purpose” strip that reads to 196 degrees (bottom row).
Installation: Before placing the temp strips on your barrel, clean and degrease the barrel with alcohol for better adhesion. Once in place, the plastic-covered strips should provide years of service. Note, we do not recommend use with high-polished blued barrels.
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Value-Priced Temp Strip 10-packs
If you have many rifles, McMaster.com (a large industrial supply house) offers the handy reversible, 7 temperature, 86F to 140F strip (item 59535K13) for $10.71 per pack of ten (10) strips. That’s an excellent value.
Another source for BAR-L Temp Strips is Neconos.com. This vendor offers Bar-L temp strips for $9.00, or $25.00 for a 3-pack. From the Neconos Online Catalog, search for “Bar-L” to find the Temp Strips. Three temp ranges are offered: 32F to 86F (Moderate Zero); 86F to 140F (Benchrest): and 86F to 194F (Gen’l Purpose). |
Controlling Ammunition Temperature is Important Too
 Keeping your loaded cases at a controlled temperature is vital for maintaining good ES and case life. At a late summer varmint match we observed pressure signs with cases that had been sitting in direct sunlight for about 15 minutes. As we were running a “moderate” RL15 load, the pressure indications were surprising. Testing over a chronograph, cases that had been sitting in direct sunlight showed velocities up to 70 fps higher than those that had been kept in the shade. Using QuickLoad’s temperature function, we calculated from the rise in velocities that case pressures had increased by over 4,000 psi–just from 15-20 minutes in direct sunlight! Accordingly, you’ll want to keep your ammo out of the sun, in an insulated container. The Igloo Ice Cube MaxCold 70 Roller Cooler can hold enough ammo for a multi-day varmint safari or a week at Camp Perry. It’s large enough to also store water bottles and cold beverages.
June 28th, 2013
When evaluating firearm finishes, one should consider hardness, chemical resistance, lubricity, abrasion resistance, and color. However, none of these factors are as critical as corrosion protection. The average firearm owner deals with corrosion more than any other finish-related problem. Accordingly, when selecting an exterior finish for the metal components of your guns, you should look for a product with superior corrosion resistance. Thanks to Cerakote, we now have some science to help you make that decision….
How well do various firearm finishes resist corrosion?
Watch the video below to find out.
Eight Gun Finishes Tested — With Surprising Results
Eight (8) various finishes are tested, including Blueing, Cerakote, DuraCoat, FailZero, Ion Bond, KG Gun Kote, NiBX, and Phosphate (Parkerizing). Eight metal firearm components (each with a different finish) are placed into the salt chamber to see how long it takes for each finish to show initial signs of corrosion. To provide a baseline for comparison, a “naked” 416 stainless steel barrel was also placed inside the test chamber. The test was started, and for each coating, the time was recorded when corrosion started to appear. FYI, if you thought “stainless steel” can’t rust, think again. The stainless barrel sample (along with the blued metal sample) showed visible corrosion after just 24 hours!
After 24 Hours in Salt Chamber
After 48 Hours in Salt Chamber
After 172 Hours in Salt Chamber
Salt Chamber Testing — 5% Salt Concentration at 95°F
According to ASTM B117-03, the Corrosion Test provides a controlled corrosive environment which has been utilized to produce relative corrosion resistance information for specimens of metals and coated metals exposed in a given test chamber. The salt chamber is set to a temperature of 95 degrees Fahrenheit with a 5% salt concentration. Salt Chamber testing is used to draw a comparison between metals and finishes and does not correlate to a specific number of hours of real world use.
Story tip by EdLongrange. We welcome reader submissions.
June 21st, 2013
Precision rifle shooters don’t have to hit a big-league fastball, or launch a top-fuel dragster in the blink of an eye. Nonetheless, reaction times are important in our sport — both for competitive shooters and hunters. Want to catch that prairie dog before he slips down his hole? You’ll need to be quick. Want to win at short-range benchrest? Then you’ll need to watch your windflags and respond quickly to a change. Miss a major wind-shift and you could ruin your whole weekend.
Here’s a fun test of reaction times from HumanBenchmark.com. The way it works is that, after clicking “Start”, you wait until the background color changes from red to green. The instant you see green, immediately click your mouse. The average (median) reaction time is 215 milliseconds. Hint: If you keep your finger “preloaded” in contact with your mouse button you can shave some milliseconds — but don’t “jump the gun”.
CLICK HERE for Reaction Time Test >>>>>>>>
Tips for Faster Times
Here are three tips to speed up your reaction times:
1) Respond to the color change (by itself), rather than wait to read the word “CLICK!” after the box shifts to green.
2) Try focusing at the corner of the box, rather than the center. This may help you react “without thinking”.
3) Have your index finger “poised and ready” over the left button–you can shave milliseconds by very slightly depressing the button before you actually click.
June 11th, 2013
In order to promote safe and secure firearms storage, the National Shooting Sportz Foundation (NSSF) has launched its S.A.F.E. Summer Campaign. S.A.F.E. stands for:
- Secure your firearms when not in use.
- Aware of those around you who should not have unauthorized access to guns.
- Focus on your responsibility as a firearm owner.
- Educate yourself and others about safe firearm handling and storage.
NSSF has pledged $1 million to provide firearms safety kits (with a gun lock) to gun owners nationwide. Several lock-distribution events will be announced in the coming weeks. Safety information will be provided through social media and the Project ChildSafe website. NSSF reminds us that firearms owners have many ways to safely store their firearms when not in use. Here are some of your options:
May 21st, 2013
 Our IT guy, Jay (aka JayChris in the Forum), was having some issues with his .260 AI. A load with known accuracy had suddenly and mysteriously stopped shooting well. Jay couldn’t figure out what was going wrong. Then he remembered he had cleaned his brass using a powerful ultrasonic machine.
He inspected his brass carefully and saw that the ultrasonically-cleaned necks were so “squeaky clean” that he was actually scratching the jackets on his bullets when seating them. As well, Jay noticed that it took more force to seat the bullets and the seating force became less uniform case to case. Jay solved the problem by applying NECO Moly dry-lube inside the necks of his brass before seating the bullets.
The Perils of Ultrasonic Brass Cleaning by JayChris
I rotate my brass so that I can keep track of each firing, so I keep a “clean/ready to load” bin and a “fired” bin. I have 400 pieces of .260 AI brass. So, all of it was on its first firing (after doing a Cream of Wheat fire-forming) until I hit the 400-round mark. To my surprise, things went south at the 500-round mark. The first time I noticed it (according to my range log) was at a match last year, when I dropped several points and had some vertical stringing issues. After that match, I had 400 rounds through the barrel and all of my brass had a single firing on it. So, it was time to clean.
 I have used an ultrasonic cleaner for a while now. I recently got a more powerful Ultrasonic cleaner, although I don’t know if that makes a difference. My brass comes out dry and squeaky. Emphasis on the “squeaky”.
I found that my new US machine may have been getting the necks TOO clean. After ultrasonically cleaning my brass, I had noticed that it required a little more force to seat the bullets, but I didn’t really think too much about it. But then, after going over my ordeal with a shooting buddy and going over my process in minutiae, we had an “AH HA” moment when it came to cleaning (he uses good ol’ vibratory cleaning).
So, I used some moly dry-lube to pre-lube the case necks and took some rounds out to test at 200 yards. I used my last known good load and sure enough, the vertical flyers disappeared! I shot two, 10-rounds groups with .335 and .353 MOA vertical dispersion, which is consistent with the results I was originally getting.
Other folks have suggested necks may get “too clean” after ultrasonic cleaning. It was pretty sobering to actually witness, first hand, what can happen when brass is “too clean”. I had read some discussions of issues with neck friction/bullet seating after ultrasonic cleaning, but, frankly, I dismissed the idea. Now I understand. The “too clean” effect doesn’t seem to affect my Dasher at all (perhaps because Dasher necks are very short), but on the bigger .260 AI, it definitely does.
Close-Up Photos of Case-Necks
Here are photos Jay took with a microscope. You can see the difference between tumbled brass and ultrasonically-cleaned brass. Jay says: “Here, in sequence, are the Ultrasound-squeaky-clean case neck, a case neck after treatment with NECO moly dry-lube (you can see the particles that will help coat the neck during seating), and, finally, the neck from a case cleaned with corncob media in a vibratory tumbler. You can clearly see how much smoother the inside of the tumbled neck is. Yes, it’s dirty, but it’s also very, very smooth.
Close-Up of Scratched Bullet
Here is a close-up of a bullet that was seated in an ultrasonically-cleaned (“squeaky clean”) neck, with no lubrication. You can clearly see the damage done to the jacket — in fact, in a couple spots you can see the lead core through the scratches! Jay also observed that quite a bit more seating force was required to seat the bullet in a “squeaky clean” neck.
NOTE: The bullet jacket is naked — NOT coated in any way. It looks a little dark because of the shadow from the microscope lens, and the high contrast.
April 13th, 2013
 Hunters and tactical shooters need scopes with good low-light performance. For a scope to perform well at dawn and dusk, it needs good light transmission, plus a reasonably large exit pupil to make maximum use of your eye’s light processing abilty.* And generally speaking, the bigger the front objective, the better the low-light performance, other factors being equal. Given these basic principles, how can we quickly evaluate the low-light performance of different makes and models of scopes?
Here’s the answer: ScopeCalc.com offers a FREE web-based Low-Light Performance Calculator that lets you compare the light gain, perceived brightness, and overall low-light performance of various optics. Using this scope comparison tool is pretty easy — just input the magnification, objective diameter, exit pupil size, and light transmission ratio. If the scope’s manufacturer doesn’t publish an exit pupil size, then divide the objective diameter in millimeters by the magnification level. For example a 20-power scope with a 40mm objective should have a 2mm exit pupil. For most premium scopes, light transmission rates are typically 90% or better (averaged across the visible spectrum). However, not many manufacturers publish this data, so you may have to dig a little.
ScopeCalc.com’s calculator can be used for a single scope, a pair of scopes, or multiple scopes. Once you’ve typed in the needed data, click “Calculate” and the program will produce comparison charts showing Light Gain, Perceived Brightness, and Low-Light Performance. In the example below, we compared a “generic” 5-18×50 Tactical scope with a “generic” 8-32 Benchrest scope.
Though the program is easy to use, and quickly generates comparative data, assessing scope brightness, as perceived by the human eye, is not a simple matter. You’ll want to read the annotations that appear below the generated charts. For example, ScopeCalc’s creators explain that: “Perceived brightness is calculated as the cube root of the light gain, which is the basis for modern computer color space brightness scaling.” In addition, the way ScopeCalc measures Low-Light Performance is pretty sophisticated: “Low Light Performance [is calculated] as the average of light gain and resolution gain through magnification, as a measure of target image acuity gain in low light similar to Twilight Performance specified by scope manufacturers. Low Light Performance calculated here is much more useful than Twilight Performance, as Twilight performance is the average of the just the objective lens diameter times magnification, while Low Light Performance is the average of the actual Perceived Brightness times magnification, which also includes the exit pupil/eye pupil relation, light transmission, approximated diffraction, as well as the perception of relative light gain. Just as with Twilight Performance, this Low Light Performance calculation does not yet include lens resolution and contrast as factors. Therefore lower quality optics will yield relatively less gains at higher magnifications.” Got that?
 *In low light, the human eye can typically dilate to 5mm – 7mm. The exact amount of dilation varies with the individual, and typically declines, with increasing age, from 7mm (at age 20) to a dark-adapted pupil of about 5.5mm by age 65. To take full advantage of a scope’s light-gathering capacity, the diameter of an eyepiece exit pupil should be no larger than the max diameter of your eye’s dark-adapted pupil, so that all of the light collected by the scope enters your eye, rather than falling on the iris. A large 8mm exit pupil may seem good, but it would be partly “wasted” on a shooter in his 60s.
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