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January 13th, 2008
Accurate, modular, and supremely versatile, the AR15 is America’s favorite semi-auto rifle. But let’s face it, the AR is a maintenance hog.
 There are various schools of thought when it comes to maintaining an AR. Some folks prefer to run their AR “dry” with minimal lube on the lugs and friction surfaces. Other shooters prefer to run their ARs “wet”, with lots of lube. But whatever your preference, you need to clean your AR regularly. And nothing is more important that the AR’s bolt/carrier assembly. Because it is involved in feeding, firing, and extracting, the AR-15 bolt/carrier assembly can be considered the most critical portion of the AR-15 system.
The editor of the Top Quark Blog has created an excellent illustrated AR15 Bolt Take-Down Guide that shows how to disassemble an AR15 bolt and carrier for regular cleaning. Even if you’re an experienced AR15 shooter, you can learn something from this page (sample at left), and you may want to bookmark it for future reference. The photos are large and clear and there are helpful hints for each step of the process.
The author knows his stuff and offers some important insights. For example, he notes that “Extractor springs in most AR15 bolt assemblies are fairly weak, and this can lead to various extraction-related failures. One of the few high points about Colt assemblies is their usage of higher-strength extractor springs. You can tell the difference by looking at the inner plastic insert. ‘Normal’ springs feature a blue plastic insert, Colt strong springs have a black insert.”
There is one notable oversight on this page — the author doesn’t cover disassembly and cleaning of the ejector assembly. This is actually quite important. A few small brass shavings, combined with carbon and lube in the ejector slot, WILL cause malfunctions. In fact, when this editor is called to diagnose problem ARs, the first things I look at (after swapping magazines) are the ejector recess and the slot for the extractor. Clogged ejectors are responsible for fail-to-ejects and other jams. It is essential that you keep the ejector hole clean. Old, gooey lube residues mixed with carbon and tiny brass shavings in the ejector recess will create all sorts of problems. As shown in the diagram below, it is simple to remove the ejector (#6) and ejector spring (#5), by drifting the ejector retaining pin (#4).
January 13th, 2008
This do-it-yourself project comes from ace silhouette shooter Larry Medler. He devised a hand-crank system for turning case necks that offers the best of both worlds — the speed and “muscle” of powered neck-turning with the “feel” afforded by manual methods. The flywheel, salvaged from an old grape crusher, delivers plenty of RPM when needed, but Larry still has total control over the neck-turning speed and torque.
Larry explains: “My neck turner is a home-made model with a 15.5″ crank flywheel. This arrangement almost makes turning necks fun. I’ve learned that the secret to neck turning is how easy it is to turn the case. If it takes too much force or effort you’re probably not going to do a good job. However, when you turn by hand you have the best feel for the cutting process. So I wanted a system that reduced the effort required, but still retained good “feel”. My hand crank system fits the bill — it makes cutting easy, but you still have good sensitivity throughout the process.
The case holder was made for 308 Winchester cartridges. The case holder fits into a rubber heater hose that connects to a 0.5-inch rod. The rod is fed through two bearing blocks which mount on a frame on my work bench. The rod is turned using a crank on the grape crusher flywheel. This system works great for neck turning. It is easy to crank and you still have a feel for how the cutter is working. While I now use an electric screwdriver to power other case prep tools, at one time I attached a variety of tools to this simple crank system.
I recently upgraded to a K&M Neck Turner (from a Sinclair previously). K&M makes a great tool. It’s easy to make very small adjustments to the cutting depth. I use the K&M case-holder that came with the neck turner for triming cases. It grips a little better than the Sinclair case-holder and both are easier to use than the Lee case-holder.”
You’ll find more helpful, illustrated tips on uniforming cartridge brass on Larry Medler’s Case Prep and Loading web page.
January 6th, 2008
Few, if any, gun safes come with adequate factory-installed lighting. Even if you have overhead lamps in the room where your safe resides, you’ll still find that the inside of your safe is dark, making it difficult to find small items. By adding interior lighting to your gun safe, you’ll lessen the chance of “bumping and grinding” your precious firearms as you move them in and out of the safe.
 Here is a simple, do-it-yourself project that costs very little money. String LED lighting is now available at low cost. Called “rope lights” or “string lights”, these are strings of LEDs in lengths of plastic tubing. Gunsafe vendors sell strings for up to $35.00 per coil, but you can buy the same products at discount chains for under $5.00. Brian J. from Virginia reports: “I just went to Wally World’s Christmas clearance section and picked up two strands of Rope Lights for $3.50 each!” He then installed the strings behind the shelves of his gunsafe, as you can see in the photos.
LEDs draw very little electrical power and have a very long life-span so you can leave your Rope Lights running continuously in winter. These will provide some warming of the air in the safe, which helps prevent rust by raising the dew point. We still recommend that you use a GoldenRod or similar warming unit, placed at the bottom of your safe, plus desiccant packs to actually absorb moisture.
 As you can see, Rope Lights provide a great lighting solution that illuminates even the small dark corners of internal shelving units. Rope Lights are easy to install. Just string the lights behind your shelves. Most safes come with a pre-drilled hole in the bottom for a dehumidifier. Just slip your Rope Light power cord through this hole and plug it into the wall.
For more tips on how to illuminate your safe and protect its contents from rust and corrosion, read our Gun Safe Buyers’ Guide. The most comprehensive Gun Safe Resource on the web, this article covers a multitude of topics including lock selection (electronic vs. manual), fire-proofing, door hinge design, water-proofing, wall construction, rust prevention, and gun safe installation.
Gun safe interior photos by Brian J., used with permission.
January 5th, 2008
Gordy Gritters is a highly-respected benchrest gunsmith who has built many match-winning and record-setting rifles. Gordy has teamed up with Grizzly Industrial to produce a high-quality gunsmithing video on DVD. In the video, Gordy shows how to chamber and headspace a match barrel using a Grizzly G0509G 3-Phase Gunsmith Lathe. Below is a segment from the DVD showing Gordy fine-tuning the headspace as he fits a BAT Machine ‘MB’ action to the barrel. Working with precise indicators, you can see Gordy set the headspace to within a few ten-thousandths of an inch.
CLICK HERE to PLAY VIDEO
(6 megabyte file — Quicktime Plug-in Required)
Click HERE for YouTube FLASH Version (Faster Download)
 On the full DVD, available from Grizzly for $59.95, you can see Gordy do the complete job of chambering a barrel from start to finish, including fitting the barrel to a custom action. Gordy gives step by step instructions for all the following operations:
1. Dialing in the barrel
2. Threading the barrel
3. Aligning the threaded shoulder
4. Predrilling/preboring the chamber
5. Reaming the chamber
6. Checking and setting headspace
7. Crowning the muzzle
8. Stamping and polishing the barrel
CLICK HERE for more photos from the DVD. The full DVD can be ordered from Grizzly’s Web Site.
January 2nd, 2008
 So what does a “worn-out” barrel really look like? Tom Myers answered that question when he removed a 6.5-284 barrel and cut it down the middle to reveal throat wear. As you can see, there is a gap of about 5mm before the lands begin and you can see how the lands have thinned at the ends. (Note: even in a new barrel, there would be a section of freebore, so not all the 5mm gap represents wear.) There is actually just about 2mm of lands worn away. Tom notes: “Since I started out, I’ve chased the lands, moving out the seating depth .086″ (2.18 mm). I always seat to touch. My final touch dimension was 2.440″ with a Stoney Point .26 cal collet.”
Except for the 2mm of wear, the rifling otherwise looks decent, suggesting that setting back and rechambering this barrel could extend its useful life. Tom reports: “This was something I just thought I’d share if anyone was interested. I recently had to re-barrel my favorite prone rifle after its scores at 1,000 started to slip. I only ever shot Sierra 142gr MatchKings with VV N165 out of this barrel. It is a Hart and of course is button-rifled. I documented every round through the gun and got 2,300 over 4 years. Since I have the facilities, I used wire EDM (Electro Discharge Machining) to section the shot-out barrel in half. It was in amazingly good shape upon close inspection.”
Tom could have had this barrel set back, but he observed, “Lately I have had to increase powder charge to maintain 2,950 fps muzzle velocity. So to set it back would have only increased that problem. [And] I had a brand new 30″ Krieger all ready to screw on. I figured it was unlikely I’d get another full season on the old barrel, so I took it off.”
January 1st, 2008
Dave Kiff of Pacific, Tool & Gauge (PT&G) has been making complete replacement bolts for Remington 700 actions for quite some time, but many of our readers may not be aware of this PT&G product. Why would one need a replacement bolt? First, this allows you to have different bolt-face sizes for the same action. For example, with two bolts you could shoot both a .308 Win and a 300 WSM from the same action. Second, the PT&G bolts are precision machined to the internal dimensions of your action. If you are having your Rem 700 action blue-printed (accurized) by a gunsmith, a new bolt from PT&G completes the job perfectly, and will give you a more precise-fitting bolt with less internal slop.
As Vince Bottomley explains, it may actually be more cost-effective to purchase a new bolt, rather than have your existing bolt milled and machined in the blue-printing process: “Accurizing a Rem 700 action is not a simple or cheap process. A lot of the work will be to the bolt itself — truing the lugs, skimming the bolt-face, fitting a Sako style extractor, new bolt-knob and maybe a new firing-pin. Even then, unless you have the bolt sleeved, it will rattle like the old clunker it probably is! Don’t waste your money! Go for one of the replacement bolts from Pacfic Tool & Gauge. PT&G offers a new bolt complete with new bolt-handle, firing pin, spring etc and the bolts come in different diameters so that you can get one to exactly fit your Remington action. This of course requires some accurate measuring, so it’s best to get your gunsmith to order the bolt. They are [a great] value and will cost a lot less than up-grading your existing bolt.”
Rem 700 replacement bolts start at about $125.00 for the bolt body only (complete bolts are also offered). PT&G bolts are available with either a standard Remington extractor or a Sako-style extractor, with .223, PPC, .308, or magnum bolt faces. The tolerances rival that of the bolts found in custom actions. You can order direct from PT&G in Oregon, (541) 826-5808, or you can purchase through vendors such as MidwayUSA.com, (bodies only, search for “PTG Bolt Body”). If you want a custom spec bolt, it’s probably best to have your gunsmith deal directly with Dave Kiff at Pacific Tool.
December 9th, 2007
Jason Baney, our 1000-yard editor, has done some pioneering work on Ultrasonic Case Cleaning. In general, ultrasonic cleaning is a “good thing” for accuracy, as it thoroughly cleans the inside of the case, preventing the stubborn build-up of soot and carbon that will eventually affect your internal case volume. However, there is one small “down-side” to ultrasonic cleaning, according to Jason.
Jason found that Ultrasonic cleaning leaves the inside of the case-necks so “squeaky clean” that there is excess friction when seating bullets. On a fired case that has been cleaned conventionally (no ultra-sound), a thin layer of carbon remains to lubricate the bullet entry and exit. To restore that lubricity in cases cleaned with ultrasound, Jason applies a dry lube to the inside of his case necks. Jason prefers the $10.95 moly dry lube kit from Neconos.com. With this kit, small carbon steel balls transfer moly to the neck when you place your brass nose-down in the container.
November 29th, 2007
 If you want to keep your wind-reading skills sharp during a long, cold winter spent mostly indoors, check out Shooter Ready, a Long-Range Shooting Simulation for home computers. A FREE DEMO is offered on the web. This is serious training software, not just a computer game. You choose the rifle, and the program provides different scenarios with various wind angles/speeds and target distances. The result of each shot is exactly calculated using ballistics formulas to show where the bullet hits on the target.
 This simulation graphically displays how wind, altitude, and temperature affect the bullet in flight. The results for distance are given in both meters and yards. The program provides a variety of atmospheric conditions and you can practice Mil Dot ranging on three targets: A 12″ X 12″ swinging plate, a 30″ X 18″ knock down plate and a regulation 72″ X 19″ knock down plate. Chose from three chamberings: .308 Winchester, (175 gr), Windrunner .338 Lapua, and 50 BMG. Each caliber has 70 different range exercises, plus an advanced stage for each caliber with 25 different timed hold-offs and moving targets. Add in different atmospheric extremes and you get almost 300 different ranging scenarios.
CLICK HERE to START DEMO
The demo has sample stages from the CD version of Shooter Ready. A basic understanding of mil dot ranging, using a range card and some exterior ballistics is recommended.
November 26th, 2007
 Forum Member Dave B., aka “Gunamonth”, is a chemist/physicist with decades of experience working with the ultrasound process. He has achieved great results cleaning cases via ultrasound. Dave tried a variety of solutions and he favors a mix of water and Citranox®. This achieved the best results, and did not require a separate neutralizing step if you rinse the cases thoroughly after. Citranox, mixed 1:75 or 1:100 with water (distilled H20 is best), is inexpensive to use. Phospate-free Citranox® contains a blend of organic acids, anionic and non-ionic surfactants and alkanolamines. For more information on using Citranox®, check out THIS FORUM THREAD.
Dave notes: “I had a lot of communication with the technical VP of Alconox about trying to clean fired cases with an ultrasonic unit. He sent me a copy of his ultrasonic cleaning manual and recommended a product called Citranox®. So far I’ve been very impressed. With once- or twice-fired brass they clean up very quickly. The worst cases I tried were 6 Dashers that had been fired ten times with Varget and never cleaned. The worst fouling was in the bottom of the case around the flash hole. They took longer and I used a more concentrated cleaning solution but they did come out clean. The price is reasonable. I paid $35 a gallon and for once- or twice-fired cases I dilute the cleaner 100 to 1. There is much less chemical reaction with the brass than there is with vinegar. No weird colors, just shiny bright. I even used it with hot water, which speeds up the cleaning process. No need to neutralize. Just rinse in running water and they’re squeaky clean. The cleaner is mostly detergents with a little citric acid. Even at a 1:75 ratio my $35 worth of cleaner will make 75 gallons of solution. It doesn’t seem to be reusable but 75 gallons is a whole lot of solution when I only use about two cups at a time.”
November 24th, 2007
What’s better than a 6BR? A 6BR that produces a LOT less noise and less than half the recoil of a bare-muzzled gun. Our friend USMA89 has a 6BR “Texas Tackdriver” with a trued Rem 700 action and Robertson Composites F-Class stock. Smithed by GA Precision, it has delivered tiny groups at 200 yards with 107 Sierra MKs. With sound suppressor in place, USMA89 tells us, it’s like shooting a 22 mag rimfire: “Shooting with a suppressor or can is a great experience. In fact, once you start shooting with one, it is hard to go back to normal shooting. The recoil reduction is amazing, cutting perceived recoil by as much as 70%. Think of a suppressor as the ultimate muzzle break that reduces sound to boot.”
The cost of a good suppressor ranges from $600-$1000, and then there is the $200 to Uncle Sam for the tax stamp and the 3-6 month wait. (Currently, 33 states allow citizens to own suppressors in accordance with Federal regulations.) The suppressor on this gun is considered one of the best, a SWR Omega. USMA89 adds: “I also use a SRT suppressor and am very pleased with it as well. The SRT costs about $300-$400 less than the SWR and you get the same amount of sound reduction.” With a quality suppressor you can get from 33 to 36 db worth of sound suppression.
Once you have gone though the hoops the government has put in your way (check your state laws also!), mounting is easy. Get a good gunsmith to thread your barrel (5/8×24 is the normal class 3 thread) and screw it on. In general suppressed guns barrels are cut shorter for balance. USMA89 explains: “I went with a 28″ barrel and with the can it is a little front-heavy, but the stock’s wide fore-end compensates for this. If this were a ‘tactical’ weapon, I would have the barrel cut down to at least 22″, maybe less. Most people that use suppressors will tell you that they shoot better groups with a can than without. This is because there is less recoil, less ‘dirty air’ behind the bullet, and (in many cases) you get improved barrel harmonics.”
To learn more about silenced weapons, read this article on Firearm Sound Suppressors by Mark White.
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