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November 13th, 2007
There was a lot of interest in Jeff Rogers’ Heavy Gun, featured in yesterday’s Daily Bulletin. Jeff is a race-car mechanic and engine builder in Australia, and you’ll find many innovative mechanical features on this rifle.
1. Drop Port for Magnum Case
Jeff reports: “The action is home-made. My shooting buddy Tony Z was the magician here–without his extensive machining experience, the action would still be on the drawing board. As you can see it is a Right Bolt, Left (loading) Port design. What makes it unique is the big gravity port, perhaps the only Drop Port ever made for a case of this size. The port will work will cases up to 2.850″ in length, with a .550″ max rim diameter.” The action is constructed from Swedish 709m chrome-moly steel measuring 2.00″ diameter x 10″ in length. It has roller-assist extraction to help with the high pressure loads Jeff runs. The action is both conventionally bedded and glued into the stock.
2. Removeable Aluminum Side Pods
The two alloy “side pods” were milled from 6061 T6 billet. Given airline weight limit of 32 kg per piece, Jeff made the pods modular (they are through-bolted), so the gun can be air-transported in two sections. Concerning the dual side-pod design, Jeff observed: “[This] is unconventional… but I wanted was something that was true [when bolted together]. Milling the thing up on every surface insured this and the pods are installed with dail indicators on assembly.”
3. Tension Barrel System
The Broughton barrel sits inside a threaded barrel sleeve that holds the barrel in tension. Tensioned barrels have been used on Heavy Guns before, but few have been as successful in competition as Jeff’s rig. Jeff tells us: “The 30-cal barrel is a 1.500″-diameter, 1:13 twist, 32″ Broughton. It is straight for 6″ then tapers to 1.250″ at 32″. The tension tube is 6061 T6 alloy 2.0″ outside diameter with a .187″ wall thickness. At the chamber end, a 431 stainless adaptor is fitted to the barrel, about 1.5″ long, stepped to a slip fit inside the tube for another 1.5 inches. This allows the main heat area of the chamber to sink into the tube. The tension tube is all jointed with a CAT high-temp anti-seize. On the muzzle end is a left hand 1.250x16tpi thread to take the tension nut. We have tried various tensions and found torque settings do not matter to the groups as long as the nut does not come loose. Because I can really rattle down those 10-shot groups with the Drop Port action, remember that the barrel grows in length before it gets a chance to transfer heat to the outer tube. If you shot the gun at pedestrian pace, then only 50 ft/lbs of tension is needed.”
November 8th, 2007
The editors of the NRA’s American Hunter magazine recently tested 10 brands of shooting glasses, determining how well the eyewear could shield users from shotgun birdshot. Eyewear samples were tested at 25, 15, 10, 8, and 5 yards, using #8 shot. One ANSI Z87.1-certified set of polycarbonate eyewear was then repeat-tested with #6 shot, #4 shot, #2 steel and buckshot.
CLICK HERE for Full TEST Report.
The tests provided some very important conclusions:
1. The glasses marked Z87.1+ (“plus” is a high-impact rating) performed the best. Overall, Z87.1-rated polycarbonate lenses provided excellent protection from birdshot at 10-15 yards and beyond. Some Z87.1+ eyewear even blocked birdshot at 8 yards.
2. You can’t necessarily rely on price as an indicator of quality. The $12 Bollé VX and the $5.95 Pyramex Rendezvous both worked better than some much more expensive brands. The $5.95 Pyramex, in fact, was one of only three products that stood up to the #8 birdshot at 8 yards. The Pyramex does carry a Z87.1+ rating.
3. Avoid no-name, un-rated plastic eyewear. American Hunter Editor Jeff Johnston writes: “It’s a mistake to assume that any plastic-lens sunglasses off the rack at the local 7-11 are made of polycarbonate and therefore are effective as shooting glasses—cheap plastics are not polycarbonates; in fact, wearing them could be worse than wearing nothing, as they can introduce sharp shards of plastic to your eyes in addition to the projectile(s) that caused them to break.”
November 6th, 2007
Here’s a simple procedure that lets you get a solid zero for a hunting rifle in just four shots. Of course you probably want to fire a few more rounds to confirm your zero before you head off to your hunting grounds, but this will let you get on-target with a minimum amount of time and ammo expended.
1. First, remove the bolt and boresight the rifle so you can see the center of the target through the bore. Secure the rifle in the rests to maintain its position as boresighted. Then, without moving the rifle, center the reticle. That should get you on paper. With the rifle solidly secured in front and rear rests or sandbags, aim at the center of a target placed at your zeroing distance (100 or 200 yards). Fire one shot. Then, return the gun to the exact position it was when you pulled the trigger, with the cross-hair centered on the target as before.
2. Locate, in the scope, where your first bullet landed on the target. Now, while you grip the rifle firmly so it doesn’t move, have a friend adjust the turrets on your scope. While you look through the scope, have your friend turn the windage and elevation turrets until the cross-hairs, as viewed through the scope, bisect the bullet hole on the target. In other words, you use the turrets to move the center of the reticle to the actual position of shot number one.
3. After you’ve adjusted the turrets, now re-aim the rifle so the cross-hairs are, once again, positioned on the target center. Keep the rifle firmly supported by your rest or sandbag. Take the second shot. You should find that the bullet now strikes in the center of the target.
4. Take a third shot with the cross-hairs aligned in the center of the target to confirm your zero. Make minor modifications to the windage and elevation as necessary.
5. Now shoot the rifle from a field rest (shooting sticks, bipod, or rucksack) as you would use when actually hunting. Confirm that your zero is unchanged. You may need to make slight adjustments. Some rifles, particularly those with flexy fore-arms, exhibit a different POI (point of impact) when fired from a bipod or ruck vs. a sandbag rest.
If you recently cleaned your rifle, you may want to fire two or three fouling shots before you start this procedure. But keep in mind that you want to duplicate the typical cold bore conditions that you’ll experience during the hunt. If you set your zero after three fouling shots, then make sure the bore is in a similar condition when you actually go out hunting.
October 25th, 2007
A quality mirage shield reduces the amount of optical distortion caused by heat waves rising from the barrel directly in front of the scope. On a hot day, after many rounds through the barrel, the benefit of a mirage shield can be quite dramatic. Benchrest shooters have used mirage shields for many years. Mirage shields can be just as beneficial for the serious varmint shooter. But, curiously, most varminters we know don’t employ mirage shields. We think they should. A mirage shield is a low-cost accessory that helps you get more hits and fewer misses.
As our friend Boyd Allen observed: “Varminters should use mirage shields. Think about it. You’ve invested thousands of dollars in a fancy varmint rifle and quality scope. You may have spent hundreds of dollars traveling to the varmint fields and spent dozens of hours loading up your ammo. Without a mirage shield on your barrel, once that barrel gets hot, you WILL get mirage effects that can make you miss a shot. A mirage shield costs just a few dollars. It really doesn’t make sense to go out to the varmint fields without one, if you plan on shooting lots of rounds. Barrel heat mirage can cause you to miss that critter, even if you have the most accurate rifle in the world.”
Dan Lilja offers a nice, wide mirage shield for $10. Dan notes: “Our benchrest mirage shield also works very well for field varmint rifles if there is a lot of action and the barrel is getting hot. The shield deflects image-distorting heat waves that come off of a hot barrel. The heat flows out past the edge of the shield and out of the line-of-sight of the rifle scope. These shields are 18” long, made of thin painted steel (like window blind material) and can be easily trimmed to length.”
Sinclair International also offers a 2″-wide venetian-blind style Mirage Shade, that costs just $3.95. It is available in two lengths, 18″ for BR barrels (item 06-7200), and 24″ for longer varmint barrels (item 06-7300). The Sinclair Shade is made of aluminum and can easily be trimmed to a shorter length. Like the Lilja shield, the Sinclair Mirage Shade attaches with adhesive-backed Velcro fasteners.
October 20th, 2007
Wipe-Out foam bore cleaner is a product we’ve used with great success on many rifles. With sufficient dwell time, it removes both carbon and copper fouling. You can combine it with Wipe-Out Accelerator or the new Patch-Out product to speed up cleaning time. Many shooters, including this editor, find that bore-brushing has been virtually eliminated with the regular use of Wipe-Out. (With some barrels however, you may still have to brush or use a bore paste if you notice stubborn carbon build-up in the throat area.)
Standard procedure with Wipe-Out is to insert your O-ring cleaning rod guide into the chamber and then squirt through the muzzle. However, this isn’t possible with all rifles. One of our readers wanted to try Wipe-Out, but he has a Remington 7400. This is a semi-automatic rifle with no pass-through in the rear of the receiver. There’s no way to insert a guide rod, and it’s also tricky to use a chamber plug.
READ Jason’s Wipe-Out Article Here
For rifles such as the Garand, M1A and other semi-autos, you can apply Wipe-Out through the breech if you use fitted, plastic tubing. Jason Baney has written a short article describing this process. In a nutshell, you need one piece of tubing that fits the chamber tightly and then connects with a second, smaller diameter tube that attaches to the Wipe-Out can. This avoids any “over-spray” of foam in the action area, providing a clean, simple solution. Just squirt for a second or so, and wait for white foam to come out of the muzzle. Be sure to keep Wipe-Out off fine wood stocks.
October 19th, 2007
Here’s a nice do-it-yourself project for the winter. Simpson, maker of Strong-Tie fasteners, offers FREE Workbench Plans for a sturdy, 48″-wide bench with a pegboard backing and both upper and lower shelves. A complete list of fasteners and cut lengths is provided. For use as a loading bench with mounted presses, you can double-up the bench-top for extra ridigity. Without much difficulty, the plans can be adapted to build a wider bench if you prefer.
The same downloadable document also contains plans for an 80″-high 6-shelf unit, a 72″-high heavy-duty shelving unit (with 4 shelves), and a 48″-wide heavy-duty table.
October 16th, 2007
 When neck-turning cases, it’s a good idea to extend the cut slightly below the neck-shoulder junction. This helps keep neck tension more uniform after repeated firings, by preventing a build-up of brass where the neck meets the shoulder. One of our Forum members, Craig from Ireland, a self-declared “neck-turning novice”, was having some problems turning brass for his 20 Tactical cases. He was correctly attempting to continue the cut slightly past the neck-shoulder junction, but he was concerned that brass was being removed too far down the shoulder.
Craig writes: “Everywhere I have read about neck turning, [it says] you need to cut slightly into the neck/shoulder junction to stop doughnutting. I completely understand this but I cant seem to get my neck-turning tool set-up to just touch the neck/shoulder junction. It either just doesn’t touch [the shoulder] or cuts nearly the whole shoulder and that just looks very messy. No matter how I adjust the mandrel to set how far down the neck it cuts, it either doesn’t touch it or it cuts far too much. I think it may relate to the bevel on the cutter in my neck-turing tool…”
Looking at Craig’s pictures, we’d agree that he didn’t need to cut so far down into the shoulder. There is a simple solution for this situation. Craig is using a neck-turning tool with a rather shallow cutter bevel angle. This 20-degree angle is set up as “universal geometry” that will work with any shoulder angle. Unfortunately, as you work the cutter down the neck, a shallow angled-cutter tip such as this will remove brass fairly far down. You only want to extend the cut about 1/32 of an inch past the neck-shoulder junction. This is enough to eliminate brass build-up at the base of the neck that can cause doughnuts to form.
The answer here is simply to use a cutter tip with a wider angle — 30 to 40 degrees. The cutter for the K&M neck-turning tool (above) has a shorter bevel that better matches a 30° shoulder. There is also a 40° tip available. WalkerTexasRanger reports: “I went to a 40-degree cutter head just to address this same issue, and I have been much happier with the results. The 40-degree heads are available from Sinclair Int’l for $13 or so.” Forum Member CBonner concurs: “I had the same problem with my 7WSM… The 40-degree cutter was the answer.” Below is Sinclair’s 40° cutter for its NT1000 neck-turning tool. Item NT3140, it sells for $12.95. There is also a slightly more expensive 40° cutter for the NT3000 tool, item NT3340.
October 10th, 2007
Past NBRSA 1000-yard Champion Jerry Tierney has been experimenting with a “super-sized” mirage shield. Like other shooters, Jerry noticed that mirage produced by barrel heat was creating optical distortions, causing groups to open up on the target. He had fitted a conventional, narrow, venetian-blind style mirage band to his barrel using velcro fasteners. This had the expected beneficial effect, until Jerry’s round count rose to the point that the barrel heat was overcoming the narrow band’s shielding effect.
Jerry figured “if a narrow band is good, maybe a wide mirage band is even better”. Jerry experimented with materials and sizes, eventually settling on a 4-inch wide section of cardboard running from the scope foreward. He wrapped the cardboard with plastic strapping tape to add stiffness, and then, during his experiments, zip-tied the cardboard to the barrel. The venetian blind band was then placed on top of the cardboard. This gives him a two-tier mirage shield.
To Jerry’s surprise, with the jumbo mirage shield in place, the barrel remained accurate for a much longer round count. Jerry told us: “I thought the barrel was ‘going off’ as it heated up. But what I found, by using the big shield, was that the barrel stayed accurate even when it was hot. The barrel actually continued to shoot very well when hot–once I started using the bigger mirage shield. Mirage was causing the accuracy problems. With the big shield in place, I can put more rounds through the tube without seeing negative effects on the target. I concluded that this gun can shoot well with a hot barrel, so long as I kept the mirage under control. I know the cardboard shield looks funky, but it works. I can shoot longer strings without losing accuracy.”
September 30th, 2007
Many of you may not have seen how Jerry Stiller’s innovative Drop-Port functions with a 6BR or 6PPC case. Well we can tell you, Stiller Precision has one slick little system. Just retract the bolt and your case exits, nose-first, through a small port, coming to rest right under the gun. It works by gravity alone so you don’t need a conventional ejector, with the case alignment issues an ejector can create. (An ejector pushes on one side of the rim–some folks think this can push the case out of “perfect” alignment.) The drop-port is available both in the aluminum Viper and the Stainless Diamondback action. Case size is limited to PPC, 6BR, and 6BR Improved case length. Our Belgian friend David Bergen was kind enough to create a video showing his Viper Drop-Port in action. NOTE: This large, 7-megabyte file is best for users with high-speed connections. Left-Click the image to stream video. Right-Click and “save as” to download the file.
Download Video | Drop-Port Blueprint
September 29th, 2007
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. To discuss the issue of rust formation on stainless steel, visit this FORUM Thread.
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