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August 25th, 2008
Some folks feel that they don’t have to worry about rust and corrosion on stainless steel barrels, actions, and other components. That’s not really true. “Stainless” is a bit of a misnomer. First, there are different types of stainless steel alloys, with different degrees of rust resistance. 300 series stainless is more corrosion resistant than the 416 stainless commonly used in barrels. The composition (by percentage weight) of 416 stainless is 0.15% carbon, 12-14% chromium and the rest iron. 416 stainless steel lacks the roughly 10% nickel content that makes the 300 series more corrosion resistant in atmospheric conditions.
Though some grades of stainless are more corrosion-resistent, ALL varieties of stainless steel can rust if they are not handled and stored properly. Forum reader Kells81 observed: “Wanna see some rusted stainless? Go to the big “C” brand store in Ft. Worth. Every stainless gun they have on the used gun rack is rusted.” Tom Easly of TRE Custom explains: “Sweat is very corrosive. Sweat and blood will rust many stainless steels. I hate to handle my guns or drip on them when I sweat. It really helps to just wipe them good with a wet rag, dry and wipe on a light coating of gun oil. I think most stainless barrels are made from type 416 stainless, and it is generally pretty corrosion resistant, but not when exposed to sweat, blood, or chlorates (corrosive priming), and some other electrolytes.”
Forum member Jacob, who is studying materials science at LSU, provides this technical information: “The basic resistance of stainless steel occurs because of its ability to form a protective coating on the metal surface. This coating is a ‘passive’ film which resists further ‘oxidation’ or rusting. The formation of this film is instantaneous in an oxidizing atmosphere such as air, water, or other fluids that contain oxygen. Once the layer has formed, we say that the metal has become ‘passivated’ and the oxidation or ‘rusting’ rate will slow down to less than 0.002″ per year (0.05 mm per year).
Unlike aluminum or silver, this passive film is invisible in stainless steel. It’s created when oxygen combines with the chrome in the stainless to form chrome oxide which is more commonly called ‘ceramic’. This protective oxide or ceramic coating is common to most corrosion resistant materials.
Halogen salts, especially chlorides, easily penetrate this passive film and will allow corrosive attack to occur. The halogens are easy to recognize because they end in the letters ‘ine’. Listed in order of their activity they are: fluorine, chlorine, bromine, iodine, astatine.
These are the same chemicals that will penetrate Teflon and cause trouble with Teflon coated or encapsulated o-rings and/ or similar coated materials. Chlorides are one of the most common elements in nature and if that isn’t bad enough, they’re also soluble, active ions. These provide the basis for electrolytes. The presence of electrolytic solutions can accelerate corrosion or chemical attack.”
 CONCLUSION: Stainless steel barrels and components won’t rust nearly as fast as blued steel, but you still have to take precautions — particularly removing sweat and corrosive salts from the barrel. Also, don’t let moisture build up inside or outside of the barrel.
We recommend wiping your barrels and actions with Eezox, or Corrosion-X after each use. These are both extremely effective rust-fighters that go on thin, without leaving a greasy residue. (Eezox leaves a clear finish, while Corrosion-X has a slightly waxy finish.) Also store your guns in Bore-Store synthetic bags when the guns go in the safe. Bore-Stores wick away moisture, and the synthetic fleece inner surface is treated with rust-fighting chemicals. Bore-Stores also protect your guns against dings and scratches. To discuss rust formation on stainless steel, visit this FORUM Thread.
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August 25th, 2008
Labor Day Weekend is coming up. Here’s a smart, simple item that will come in handy during hot summer weather. The Solarstop elastic hatband will fit over the crown of any baseball-style cap. (Yep, you’ve probably got dozens of baseball caps, right?). The draped fabric provides 30+ UPF protection for your neck and ears. When things heat up, dunk the soft microfiber fabric in the water for relief–it cools you down fast and dries quickly.
 This smart accessory is sold by Cabelas.com, CampMor.com, and Great Outdoors Depot, for $9 to $12.00. Campmor also offers the similar “Sunday Afternoons Solarweave Cap Curtain”, featuring 50+ UPF quick-drying supplex nylon that blocks 97% of UVA and UVB rays. The Cap Curtain features decorative webbing in the front with a velcro sizing adjuster in the back.
These designs are simple enough that anyone with basic sewing skills could make their own cap-top neck drape in a few minutes. (If the wife has a sewing machine this would be a snap). If you make your own unit, be sure to use sun-blocking fabric. Plain cotton or polyester won’t work as well. UV protection is key.
[Editor’s Note: Why, you may ask, am I recommending this somewhat goofy-looking product, and why have I featured sun hats previously in the Bulletin? Well, the risk of skin cancer is very, very real. I just had a basel cell carcinoma removed last week. Trust me, sunscreen and ear/neck protection is a lot cheaper than going to the doctor. Folks who spend much time in the sun really need to watch this stuff–get yourself examined every year. A malignant melanoma can kill you in a few months. Early detection is vital.]
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August 24th, 2008
This may surprise you. We’ve learned that time (between neck-sizing operation and bullet seating) can have dramatic effects on neck tension. Controlling neck tension on your cases is a very, very important element of precision reloading. When neck tension is very uniform across all your brass, you’ll see dramatic improvements in ES and SD, and your groups will shrink. Typically you’ll also see fewer fliers. Right now, most reloaders attempt to control neck tension by using different sized neck bushings. This does, indeed, affect how firmly the neck grips your bullets. But time of loading is another key variable.
 James Phillips discovered that time is a critical factor in neck tension. James loaded two sets of 22 Dasher brass. Each had been sized with the SAME bushing, however the first group was sized two weeks before loading, whereas the second group was neck-sized just the day before. James noticed immediately that the bullet seating effort was not the same for both sets of cases — not even close.
Using a K&M Arbor press equipped with the optional Bullet-Seating Force Gauge, James determined that over twice as much force was required to seat the bullets which had been neck-sized two weeks before. The dial read-out of seating force for the “older” cases was in the 60s, while the seating force for the recently-neck-sized cases was in the 20s. (These numbers correspond to pounds of force applied to the bullet). Conclusion? In the two weeks that had elapsed since neck-sizing, the necks continued to get tighter and stiffen.
Lesson learned: For match rounds, size ALL your cases at the same time. If you want to reduce neck tension, load immediately after sizing.
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August 24th, 2008
Mike Ratigan, author of the definitive print guide to benchrest shooting, Extreme Rifle Accuracy, knows the importance of a smooth-tracking stock. A gun that recoils more consistently is easier to shoot accurately. Reducing friction on the fore-end and toe of your riflestock can help the gun track better in the bags. The easiest way to reduce friction is to apply stock tape. Ratigan says the best stuff he’s tried is clear 3M-brand Teflon® tape. According to Mike it adheres well, lasts a long time, and reduces friction “as well as anything you can buy”. Mike reports “You won’t wear this stuff out–it’s basically a permanent fixture”. The tape is sold by Ron Hoehn, Hoehn Sales, Inc., (636) 745-8144. Ron’s 5-mil thick Teflon tape kit ($7.00) is enough for two rifles, with 5″x5″ sections for the front and 2.5″x6″ panels for the rear.
You can purchase a Teflon stock tape kit from Sinclair Int’l for $12.50. This has four 5″x5″ segments, enough for two rifles. But if you have a large collection of rifles, you’ll save big bucks by buying directly from a bulk tape supplier. C.S. Hyde Company, CSHyde.com, (800) 461-4161, sells 6″-wide, flexible Teflon-coated and UHMW tapes that work great, with either rubber, silicone, or acrylic adhesives. The price works out to about $1 per rifle.
MiKe Ratigan recommends the “Skived” (blade sliced) PTFE Teflon .005″ tape with silicone adhesive, item 15-5S. This is very low-friction and highly conformable, so it bends easily around your stock contours. You’ll need to call for custom 5″ or 6″ widths, and expect to pay about $50 for a 5-yard-long (180″) roll.
A less expensive option is the UHMW (ultra-high molecular weight) Polyethylene Tape with High Stick Acrylic Adhesive, item 19-5A. C.S. Hyde explains: “UHMW Polyethylene provides a nonstick, low-friction surface similar to PTFE tape but with much higher abrasion and puncture resistance. It is ideal for anywhere high-pressure sliding contact occurs.” The price is just $33.96, for a 6″-wide by 5 yard-long roll, enough for 36 rifles! Compare that to spending $12.50 for four 5″x5″ pieces. On Benchrest.com, AbinTX reported that C.S. Hyde “sent [him] samples of various thickness to try out before ordering. They will price a roll for you depending on how wide and how long you want.”
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August 23rd, 2008
Sinclair International, a leading vendor for precision reloaders and competitive shooters, has added Nightforce Optics to its inventory of products. Nightforce scopes remain the first choice of most top long-range shooters, including F-Class National Champions. The Benchrest and NXS models offer high magnification (up to 42 power), clear, sharp optics, and very reliable and repeatable windage and elevation adjustments. Nightforce also offers a large variety of reticles. How good is the glass? With a 12-42 Nightforce BR or NXS, in ideal conditions, you can see 6mm bullet holes “in the white” at 600 yards (not razor sharp mind you — but enough to see shot placement on a white background). We just confirmed this ourselves this past weekend. Of course, viewing conditions truly have to be absolutely “perfect” (no mirage) to see 6mm holes at 600 and such conditions are normally short-lived, but the resolving capability is there with the high-magnification Nightforces.
Sinclair’s pricing is competitive with other authorized Nightforce vendors. For example, the
12-42x56mm Nightforce BR scope (item 72-1040/45) is $1306.00 while the 8-32×56 Benchrest model (item 72-1030) is $1211.00.
Shown above are some of the most popular reticles, but others are offered. CLICK HERE to view Nightforce’s complete selection of reticles.
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August 23rd, 2008
The NRA’s American Rifleman Online website has an excellent article this month that shows how to construct a rock-solid Reloading Bench. There are plenty of photos, and a detailed set of Bench Blueprints showing all dimensions and listing all needed materials. This bench is very well designed, with many deluxe features, such as an upper drawer with fitted slots for die boxes, and large lower drawers with 100-lb rated slides to store heavy materials or tools. If you have good wood-working skills this would be an excellent project for the fall or winter (but if you’ve never done anything but assemble IKEA furniture, you may want to stick to a simpler design).
The author, Dave Campbell, offers good advice on building the bench top: “I ripped a sheet of 3/4″ AC plywood into two 24″ wide pieces and cut them to 72″ long. Then I glued them together to form a 72″ long, 1 1/24″ thick top. The trick here is to keep the edges smooth and flat so that the laminate will adhere properly and without voids. I chose a light grey laminate finish for the top because it’s easier to see what I am working on and keep clean. If you have never worked with laminate, remember it’s prudent to glue and rout the edges flush before gluing on the top. The top was attached to the carcass with eight steel L-shaped angle brackets and No. 10×1 1/4″ wood screws.”
Photos Copyright © 2008 The National Rifle Association, used by permission
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August 22nd, 2008
At the recent IBS 100/200 Yard Nationals, Benchrest legend Tony Boyer shot a spectacular 0.1697 Grand Agg in the Heavy Varmint class (0.1552 at 100, and 0.1843 at 200). This is the combined, distance-adjusted average group size for five targets at 100 yards and five targets at 200 yards. Interestingly, Tony was shooting a very unusual new gain-twist barrel from Bartlein Barrels of Wisconsin. A “gain-twist” barrel has rifling with a variable twist rate, that starts with a slower twist and transitions into a faster twist. The barrel used by Boyer had a very slight gain twist: 1:15″ twist at the breech end, increasing to 1:14.25″ at the muzzle.
Gain twist barrels are nothing new. Barrel-makers in the 19th century experimented with gain twist. More recently, Dan Lilja did quite a bit of testing with gain-twist barrels in the 1980s. However, Lilja concluded that gain twist offers no accuracy advantages: “You get just as good or better accuracy with a standard twist…just as long as the twist remains exactly the same the entire length of the bore.” (See Elements of Accuracy Article.)
 Gain Twist — Does It Offer an Accuracy Advantage?
Given Boyer’s impressive performance, maybe it’s time to revisit gain twist technology. The theory is that a slower initial twist rate may be “kinder” to bullets as they start to engrave in the rifling. There may be some slight velocity advantages as well.
Frank Green of Bartlein barrels has noted: “Gain twist type barrels have been around forever. It was used a lot back in Pope’s day with the false muzzle loaders shooting lead bullets. A lot of lead bullet shooters and rimfire shooters have asked us to do [gain-twist] barrels for them. Also shooters shooting the new, solid, machined-type bullets with driving bands on them want a gain twist type barrel. Supposedly it’s easier on the driving bands as the bullet enters the rifling. Also in bigger calibers like 20mm the gain twist is used. Mostly because you are starting a very heavy bullet into the barrel.
At Bartlein, we designate gain-twist type rifling as “T” style rifling (“T” for transitional). Why? Simply because we can cut [many variations]: straight conventional-style twist, a very uniform slow gain-type twist, or a radical gain-type twist. We can [create] anything the customer wants. The tooling still plays a part and can effect the cost of the barrel on a gain type twist.
Is gain twist for everyone? At this point in time I would say no still. Also remember, way back when, gain twist type barrels had a radical type gain. The one that Tony and couple of other guys have are not a drastic type gain. The [gain twist barrel] that Tony has only goes from a 1-15 at the breech to 1-14.25 at the muzzle. It didn’t seem to hurt him at all at the Nationals. He picked the twist and we made it for him.
I would agree with the general statement that most gain twist type barrels don’t shoot conventional jacket/lead core bullets well or should I say [they can be] temperamental. However, a slight gain seems to be OK after what Tony did.”
Lou Murdica has been evaluating Bartlein gain-twist barrels with a 1:14″-1:13.25″ twist. Lou won a Benchrest match with a 14-13.25 Bartlein gain-twist in Sacramento convincingly, and Lou told Bartlein that a similar gain-twist barrel on Lou’s railgun has been very accurate and ultra-consistent when tested with a wide variety of bullets. Lou can’t speculate as to why, but the Bartlein gain-twist BR barrels appear to be working extremely well and are not finicky about bullet choice.
Tony Boyer photo courtesy IBS.
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August 22nd, 2008
Hexagonal Boron Nitride (HBN) is an advanced bullet-coating material. HBN, also known as ‘White Graphite’, has similar (hexagonal) crystal structure as graphite, though it is a much better lubricant. For those who prefer shooting coated bullets, HBN appears to have many advantages over molybdenum disulfide (moly). First, it is much more slippery, so it can reduce friction more effectively. Second, it goes on clear, and when applied correctly it doesn’t leave a dusty, chalky finish that can come off on your fingers. Most importantly, HBN will not react with moisture to leave potentially harmful chemicals in your barrel.
Boron nitride-coated DTAC bullets are sold by Superior Shooting Sytems (David Tubb). Tubb’s company also offers HBN bullet-coating services for a fee (minimum quantity 1000). However, many shooters want to plate their own bullets with Boron Nitride. Lowerfriction.com sells hexagonal boron nitride dry lubricant powder in 1-lb and 10-lb quantities. The two particle sizes appropriate for bullet coating are 70 nm (MK-hBN-N70-Nano) and 0.50 micron (MKhBN-050). Some shooters prefer the smaller 70 nm version, while others say the larger 0.50 micron works fine. Lowerfriction.com sells 70 nm HBN for $90.00 per pound, and the 0.50 micron HBN for $79.00 per pound. CLICK HERE for order page.
Lowerfriction.com allows provides instructions for coating bullets with Tungsten Disulfide (WS2), but company technicians say the same procedure can be used with HBN:
Tumbling/Vibratory bowl coating
This method is ideal for bullets and other small parts. Speed and friction determine how effectively the material bonds to the part. The greater the speed and the pressure of application, the greater the bond. For best results use a power tool. A buffing wheel, Dremel tool or even a hone can be used.
Clean and degrease the part.
Take 5-6 small empty plastic bottles (empty aspirin bottles will do). Put few parts in the bottle and fill the bottle (up to 75%) with WS2 powder. Fill all bottles likewise.
Put the bottles in vibratory bowl/tumbler with sand or vibratory media.
Vibrate/Tumble for 4-5 hours.
Empty the bottles (you can reuse WS2) and wipe clean the parts with soft tissue/cloth. |
Bullet Coating — Step by Step with Photos
A photo-illustrated Guide to Bullet Coating is available on the WrzWaldo website. This site is maintained by a Pacific NW shooter who retails 0.5 Micron Tungsten Disulfide (WS2) and will soon be offering Hexagonal Boron Nitride (HBN) as well. The website shows how to plate bullets using 0.177″ BBs in pill bottles, which are then agitated in a vibratory tumbler. This is a simple procedure that isolates the plating media from your tumbler, and covers the bullets very completely in 30-40 minutes. WrzWaldo says his method works equally well for both Tungsten Disulfide (WS2) and Boron Nitride (HBN). The photos below show bullets coated with WS2.
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August 21st, 2008
High Power shooters have a bunch of gear to carry to the firing line–pad, shooting jacket, scope stand, spotting scope, ammo, log-book and rifle(s). If you’re shooting F-Class, add a heavy front rest and 15-lb sand-bag to the list. A range cart makes life much easier, particularly if the shooting area’s a long way from the parking lot. Creedmoor Sports makes a folding range cart that is very popular with the iron sights crowd. This unit features 14″ ball-bearing wheels and the frame is made from solid aluminum–not lightweight tubing that can bend or crack. Lift a simple locking lever and the cart folds. The cart can be completely dis-assembled, without tools, to fit in a suitcase (collapsed size 30″ x 17″ x 8″). The Creedmoor cart retails for $499.00, and that includes a rifle case, tray, and rain-cover. The rifle case doubles as a rack/holster.
If $499.00 isn’t in the budget, or you’d like to build your own range cart with a lockable storage compartment, you should look at the carts used by Cowboy Action shooters. These wooden carts are heavy, but they provide a stable platform for multiple guns and a nice, solid perch for sitting. There are many do-it-yourself designs available. One of our favorites is the GateSlinger cart shown below. This well-balanced design breaks down into two pieces for transport. Click Here for cart plans, and read this “How-to Article” for complete instructions with many photos.
| The least expensive way to go is to purchase a Dolly (Hand Truck) at Harbor Freight, or a large warehouse store such as Home Depot. Make sure to get one with wheels at least 10″ in diameter, or you’ll have problems in rough terrain. The bigger the wheels the better. Normally you can find dollies for under $30.00. Just bolt a large box or milk crate to the bottom, and voilà, instant range cart. You can clamp a piece of wood at the top with slots for barrels on one side and a flat tray for ammo on the other. Use bungee cord or leather straps to hold the barrels in place. Having built a couple all-wood range carts (both collapsible and one-piece), this editor can assure you that starting with an inexpensive welded hand truck is the cheapest, simplest way to go overall. You can buy oversize, spoked wheels from NorthernTool.com. (From the Northern Tool home page, search for “spoked wheels”.) |
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August 21st, 2008
 Beijing isn’t the only location where shooters from many nations are competing this month. The United States Int’l Muzzle-Loading Team turned lead bullets and shot into gold, silver and bronze medals at the 23rd World Muzzle Loading Championships, held August 11-16 in Adelaide, Australia. 205 competitors, representing 17 nations, vied for honors with a variety of muzzle-loading arms, ranging from matchlock muskets to sophisticated percussion target rifles and pistols. Both original antiques and modern replica guns are used, competing in different divisions.
Top honors were taken by Dr. Michael Arnette, whose score of 93 in the original division of the “Lamarmora” 50-meter offhand percussion rifle-musket event not only won the gold, but set a new world record in the process. Arnette took the same gun to the 100-meter line for the “Minie” prone match, shooting well enough to help a team of Arnette, Allan Godshalk, Gary Crawford, Frank Kapper, and Tony Ulisse take 3rd place in the “Grand Prix de Versailles”, an aggregate for military longarms that is often considered the overall world team championship. An equally strong performance was turned in by Harry Sparks, who took both gold and bronze in individual shotgun events.
CLICK HERE for Photo Gallery from Adelaide
The World Muzzle Loading Championships are held biennially, with Pacific and European Zone Championships in the off years. The 24th World Championships will be held in Portugal in August 2010. CLICK HERE for more info on precision long-range muzzle-loader shooting.
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August 20th, 2008
Recently we covered the first SoCal Rimfire Tactical Precision Match. Your editor had a chance to attend the second match on August 9. I can testify that match Director Bill Irwin presided over a fun, well-orchestrated competition with an interesting variety of stages. Competitors engaged paper targets and steel at various distances, plus clay birds and other reactive targets. For one stage, Irwin set building nails set in vertical sticks. The object was literally to drive the nails into the wood with your 22LR bullets. Easier said than done, I assure you. Here’s a “highlight video” from the August 9, match.
Stills courtesy RKSimple and Shooter65
SAKO FinnFire ‘Range’ — Accurate, Ergonomic, and RELIABLE
To my surprise, at the match I witnessed quite a few malfunctions, both in bolt-action rifles and self-loading 22s. One 10/22 was particularly troublesome, and the normally reliable Savage MKII BTVS models gave some problems when cycled rapidly. One rifle that ran flawlessly throughout the match was the handsome SAKO FinnFire ‘Range’ belonging to Mark E. from Huntington Beach.
This gun has a stock that is virtually identical to the stocks on Tikka’s centerfire Master Sporter rifles. With that stock, the FinnFire boasts ergonomics and dimensions similar to a centerfire tactical rifle, making it ideal for cross-training. Mark talks about his FinnFire in the video below.
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