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November 30th, 2012

Reloading Tip — Eliminate ‘Static Cling’ in Powder Measures

In the wintertime, it’s common to encounter problems with static electricity when throwing your powder charges. The static can cause powder kernels to cling to the surface of reloading components, and can cause powder clumping. Clumped or sticky powder may make your measure bind or grab in the middle of the cycle, which can throw off your charge weight. Here are a couple simple ways you can minimize the effects of static electricity and improve the consistency of your powder measuring.

Harrells Powder Measure Alligator grounding clips bounce cloth

Ground Your Powder Measure — If you’re throwing powder charges in the fall or winter and have problems with bridging or sticking powder, use a ground wire. Bullet-smith Victor Johnson (Johnson Precision Bullets) tells us: “I have a 25-foot piece of real small wire with alligator clips on each end. It’s that long so I can run it down the hall to a water pipe. Use the wire tie from a bread bag to hold it in a small roll to put in the range box. When using it at the range use a 6″ nail from the co-op or Lowe’s / Home Depot and just push it into the ground.”

Use Bounce Dryer Sheets — A quick pass with the thin sheets used in dryers will eliminate “static cling” on your plastic reloading parts like powder throwers, powder funnels, and reloading press guides. Thanks to Doc76251 for this tip.


Reduce Electronic Scales’ Drift with Anti-Static Spray

Reloading Tip by German Salazar from RiflemansJournal.com

Digital Scale Static Guard Static ElectricityApparently reducing static charges on and around electronic scales can reduce their propensity to drift, lessening the problem of “wandering zero”. Just how and why static charges interfere with scale performance is unclear, but many shooters have noticed that static electricity can cause electronic scales to behave strangely. So how do you reduce static charges around your digital balance? German Salazar has found a very simple solution — an anti-static aerosol spray — that, by all indications, actually works. When this “spray-can solution” was suggested to German by a fellow shooter, German was skeptical. However, German tried the stuff and he says that it really does help the scale maintain zero over time, with much less observed drift.

On his Rifleman’s Journal website, German explains that the use of “Static Guard” spray helped mitigate the problem of a drifting zero on his Ohaus Navigator electronic scale. German writes: “My electronic scale… suffers from drifting zero (as they all seem to). I’ve read dozens of forum posts about drift and how to minimize its occurrence, so I know this problem isn’t limited to my scale or my workshop. Sometime last year, John Lowther mentioned the use of anti-static spray as a solution to the drift problem. John stated that the spray had virtually eliminated drift for him.”

Digital Scale Static Guard Static Electricity

German found that the Static Guard actually worked: “The spray works great, just as John said it would. I spray all surfaces that I touch with my hands and arms as well as the pan (top and bottom), the metal tray on which the pan rests and the table under the scale. In six months or so of using the spray I’ve re-applied it about two or three times; it certainly isn’t something that you need to do each time you sit down to load. Before using the spray, it was not uncommon for me to re-zero the scale 10 times in the course of loading 72 rounds; now it might need it once during a session.”

READ Full Story on RiflemansJournal.com

Permalink Reloading, Tech Tip 8 Comments »
November 20th, 2012

Barrel Depreciation and the True Cost of Shooting

reloading shot cost barrelHow much does it cost you to send a round downrange? Ask most shooters this question and they’ll start adding up the cost of components: bullets, powder, and primers. Then they’ll figure in the cost of brass, divided by the number of times the cases are reloaded.

For a 6BR shooting match bullets, match-grade primers, and 30 grains of powder, in brass reloaded ten times, this basic calculation gives us a cost per shot of $0.51 (fifty-one cents):

Bullet $0.33 (Berger 105 VLD) Grafs.com
Primer $0.02 (Tula/Wolf SmR magnum) PVI
Powder $0.08 (Reloder 15 @ $19.15/lb) PVI
Brass $0.08 (Lapua @ $82.30/100, 10 reloads)

Total = $0.51 per round

NOTE: If you shoot a larger caliber that burns more powder, and uses more expensive bullets and/or brass, your total cost per round will be higher than $0.51.

$1.00 Per Shot True Cost? Yikes!
OK, we’ve seen that it costs about $0.51 per round to shoot a 6BR. Right?

Wrong! — What if we told you that your ACTUAL cost per round might be closer to double that number? How can that be? Well… you haven’t accounted for the cost of your barrel. Every round you fire down that tube expends some of the barrel’s finite life. If, like some short-range PPC shooters, you replace barrels every 700 or 800 rounds, you need to add $0.60 to $0.70 per round for “barrel cost.” That can effectively double your cost per round, taking it well past the dollar per shot mark.

Calculating Barrel Cost Per Shot
In the table below, we calculate your barrel cost per shot, based on various expected barrel lifespans.

As noted above, a PPC barrel is typically replaced at 700-800 rounds. A 6.5-284 barrel can last 1200+ rounds, but it might need replacement after 1000 rounds or less. A 6BR barrel should give 2000-2600 rounds of accurate life, and a .308 Win barrel could remain competitive for 4,000 rounds or more.

The table below shows your barrel cost per shot, based on various “useful lives.” We assume that a custom barrel costs $540.00 total to replace. This includes $300.00 for the barrel itself, $200.00 for chambering/fitting (conservative number), and $40.00 in 2-way shipping costs. These are typical costs shooters will encounter when ordering a rebarreling job.

The numbers are interesting. If you get 2000 rounds on your barrel instead of 1000, you save $0.27 per shot. However, extending barrel life from 2000 to 3000 rounds only saves you $0.09 per round. The longer you keep your barrel the more you save, but the savings per shot decreases as the round count increases.

How to Reduce Your TRUE Cost per Round
What does this tell us? First, in figuring your annual shooting budget, you need to consider the true cost per round, including barrel cost. Second, if you want to keep your true costs under control, you need to extend your barrel life. This can be accomplished in many ways. First, you may find that switching to a different powder reduces throat erosion. Second, if you’re able to slow down your shooting pace, this can reduce barrel heat, which can extend barrel life. (A varminter in the field is well-advised to switch rifles, or switch barrels, when the barrel gets very hot from extended shot strings.) Third, modifying your cleaning methods can also extend the life of your barrel. Use solvents that reduce the need for aggressive brushing, and try to minimize the use of abrasives. Also, always use a properly fitting bore guide. Many barrels have been prematurely worn out from improper cleaning techniques.

Permalink - Articles, Reloading, Tech Tip 12 Comments »
November 13th, 2012

Upgrade for Caldwell Fire Control Joystick Front Rest

Available for under $180.00 including front bag, the Caldwell Fire Control front rest is a remarkable value. It makes the co-axial, joystick design more affordable than ever. We used the Fire Control front rest when testing our Ultimate Varminter 20 Practical AR. Once we removed some sand from the tri-lobe front bag, the rest worked quite well.

Get a Fire Control Rest for Just $179.40
Amazon.com
currently sells the Fire Control rest (item 956104) for $179.40. That’s a really spectacular deal for guys on a tight budget, looking to try out a joystick-style front rest. With the conversion described in this article, you can put together a system that works pretty darn well, and is more than adequate for many applications, including prairie-dog hunting (from a bench).

While most Fire Control owners are happy with the product, many have wanted to replace the tri-lobe front bag with a more conventional front bag from Protektor or Edgewood. This isn’t as easy as it looks because the width of the Fire Control top is too narrow for most standard 3″-wide front bags. On a “special order” basis, Protektor has crafted some narrower leather front bags that fit pretty well, but some shooters have decided to “upgrade” the entire front assembly.

Forum member Doug M. (aka DrJeckyl), has come up with an elegant solution that allows a Sinclair Int’l Benchrest Rest Top to be fitted to the Fire Control Rest. Doug notes: “The Caldwell Fire Control is a nice rest for the money, but it comes up short in the rest top department. The Sinclair RT-3 [or its replacement, the Gen II B/R top] fits perfect with minor modifications.” Shown below are the main components:

fire control rest conversion

To adapt the Sinclair RT-3 or Gen II B/R top, Doug merely had to drill a couple holes in the RT-3 baseplate, and adapt a spacer to get the height correct: “The Caldwell factory top has a raised mounting portion so a 1/8″ piece of stock will be needed as a spacer to the flat-bottom RT-3. The spacer needs to be cut to the same length as the movable portion on the rest. And you should plan the mounting accordingly so the left thumbscrew clears the vertical height column at full left position (there is a cutaway in the rest under the thumbscrew that allows for easy access to the screw).” We have labeled the photo with dimensions, but Doug cautions you should measure your own original plate to insure the drill locations are correct for your unit.

fire control rest conversion

Below you’ll see the completed installation, with the RT-3 installed on the Fire Control rest. Doug says it works very well. For more information on this Fire Control rest top conversion, with Doug’s measurments for the hole-spacing and his specs on the fasteners, go to the original thread in our Shooter’s Forum. NOTE: Sinclair no longer sells the RT-3 top, but Sinclair’s $69.95 Gen II B/R top can be converted just as easily. LINK to Fire Control Rest Top Conversion Forum Thread.

fire control rest conversion

Permalink Gear Review, Tech Tip 1 Comment »
October 23rd, 2012

Tech Tip: Same Load Varies in Velocity with Different Barrels

Put the same load in a variety of barrels (with the same length and chamberings) and you’ll see a wide variance in muzzle velocity. In fact, it’s not unusual to see up to 100 fps difference from one barrel to the next. We demonstrated this with a comparison test of Lapua factory ammo.

Chron Testing Lapua Factory Ammo
At our Southern California test range, we chronographed Lapua 105gr 6mmBR factory ammo in three different 8-twist barrels of similar length. The results were fascinating. Lapua specs this ammo at 2790 fps, based on Lapua’s testing with its own 26″ test barrel. We observed a speed variance of 67 fps based on tests with three aftermarket barrels.

barrel speed testing

Brand ‘S’ and Brand ‘PN’ were pre-fit barrels shot on Savage actions. Brand ‘K’ was fitted to a custom action. All test barrels were throated for the 100-108 grain bullets, though there may have been some slight variances in barrel freebore. With a COAL of 2.330″, the rounds were “jumping” to the rifling in all barrels. Among the four barrels, Brand ‘PN’ was the fastest at 2824 fps average — 67 fps faster than the slowest barrel. Roughly 10 fps can be attributed to the slightly longer length (27″ vs. 26″), but otherwise this particular barrel was simply faster than the rest. (Click Here for results of 6mmBR Barrel Length Velocity Test).

Results Are Barrel-Specific, Not Brand-Specific
These tests demonstrate that the exact same load can perform very differently in different barrels. We aren’t publishing the barrel-makers’ names, because it would be wrong to assume that ‘Brand X’ is always going to be faster than ‘Brand Y’ based on test results from a single barrel. In fact, velocities can vary up to 100 fps with two identical-spec barrels from the SAME manufacturer. That’s right, you can have two 8-twist, 26″ barrels, with the same land-groove configuration and contour, from the same manufacturer, and one can be much faster than another.

Don’t Demand More Than Your Barrel Can Deliver
We often hear guys lament, “I don’t get it… how can you guys get 2900 fps with your 6BRs and I can only get 2840?” The answer may simply be that the barrel is slower than average. If you have a slow barrel, you can try using more powder, but there is a good chance it may never run as fast as an inherently fast barrel. You shouldn’t knock yourself out (and over-stress your brass) trying to duplicate the velocities someone else may be getting. You need to work within the limits of your barrel.

Factory Ammo Provides a Benchmark
If you have a .223 Rem, 6BR, .243 Win, 6.5×47 Lapua, 6.5×55, .308 Win, 30-06, or 300 WM Rifle, we recommend you buy a box of Lapua factory-loaded ammo. This stuff will shoot great (typically around half-MOA), and it can give you a baseline to determine how your barrel stacks up speedwise. When you complete a new 6BR rifle, it’s wise to get a box of the factory ammo and chronograph it. That will immediately give you a good idea whether you have a slow, average, or fast barrel. Then you can set your velocity goals accordingly. For example, if the factory 6BR ammo runs about 2780-2790 fps in your gun, it has an average barrel. If it runs 2820+ in a 26″ barrel (or 2835 fps in a 28″), you’ve got a fast tube.

Permalink Gunsmithing, Tech Tip 21 Comments »
October 15th, 2012

Quick Tips for Reloading the 6mmBR Cartridge

One of our readers has been shooting his 6BR with considerable success in tactical/practical matches. Thus far he’s been using Lapua factory-loaded 105gr ammo. The factory ammo has delivered superb accuracy for him — under 1/4 MOA at 100 yards. Now, he is making the jump into reloading. He asked for some tips on working up a good load for an 8-twist 6BR with a no-turn neck, and selecting reloading tools. Since other readers may be 6BR novices as well, here are some helpful hints…

Accurate Reloading Tips for the 6mmBR Cartridge

6mmBR reloading tips▪ Brass Prep — You need to look at the flash-holes to make sure they’re not occluded. A few lots of Lapua brass came with a little sliver/flake of brass in the hole, sort of like a quarter moon. You can clean that up with an inexpensive pin vise. Otherwise, there is no need to ream flash holes or uniform primer pockets.

▪ Neck Chamfering — You want to develop a good feel for neck chamfering. You don’t want/need to remove a lot of brass — just knock off the sharp edge. I use a Forster 45 deg “rocket” tool. It works fine. After a couple light turns, spin backwards to smooth the cut and then finish with a twist with a green scotch pad. If you use a deep-angle chamferer, be very careful not to overcut and remove too much brass.

▪ Neck Tension — On brand new, unfired Lapua 6BR brass, neck tension is excessive. You should run an expander mandrel down the case necks before the first firing. This will reduce the neck tension while it fixes necks that may be dented or out of round. After the first firing, we suggest sizing the necks so that, after they come out of your sizing die, the neck outside diameter (OD) is .002″ less than the neck diameter of a loaded round with bullet seated. If that doesn’t work, try the next size up bushing for .001″ tension. Many top shooters like low neck tension, but we’ve also seen heavy tension work. The .002″ under loaded OD is a good starting point with the 6BR. (But note — if you have thin-walled turned necks, you may need to use a smaller bushing, running your sized necks .003 or .0035 under the OD of a loaded round.)

▪ Primers — A lot of guys like the CCI 450 primers. They’re a lot cheaper than the Federal and CCI BR primers and may give a little more velocity. The cups are also hard, which lets you run faster loads with less concern about cratering. Wolf/Tula primers also have hard cups, but you must make sure to seat them deep enough.

▪ Load Development and Bullet Choice — With the 6BR and 100-108gr bullets, load development should be relatively easy. With Varget, Reloder 15, Norma 203B, or VV N150, between 30.0 and 30.7 grains should work as your final load. My match load is 30.3 Varget and that has shot under 2.0″ at 600 yards. Start at 29.0 grains and and work up in 0.2 grain increments, checking for pressure. DO weigh every load… twice. If possible, use a chronograph during your load work-up. 2880-2920 fps is a nice “sweet spot” for the 6BR, but slower can be very accurate too. (With custom actions, tight chambers, and long barrels, some guys are going even faster — but that’s hard on brass.)

If you have a barrel on the slow side, consider shooting the Berger 100gr ‘Match Target’ BTs. These bullets are very accurate, and we’ve found that you can drive them 75-100 fps faster than the Berger 108s or Sierra 107s at similar pressure levels. With the 100-grainers, you may find that you can hit a superior velocity/accuracy node, so they may shoot better overall than the 105-108 class bullets. Varget, RL15, and IMR 8208 all work great with this 100gr bullet.

For shooting from 300-500 yards, you should consider the lighter-weight bullets: Sierra 95gr MK, Lapua 90gr Scenar, Berger 95gr and 87gr VLD. The Sierra and Lapua bullets are very accurate and not sensitive to seating depth. In addition to the powders mentioned above, H4895 and IMR 8208 XBR work very well with the 90-grain-class bullets. One note about the smaller Berger VLDs — the Berger 95gr VLD and 87gr VLD both have very short bearing surfaces, so they work best in a chamber with a short-to-moderate Freebore. We had the best luck with the 95gr VLD about .010″ into the lands. We could achieve that with an 0.075″ Freebore chamber. But you won’t be able to hit the rifling with the 95s in a long-throated chamber. With this bullet we recommend sorting bullets by base to ogive.

Berger 87gr VLDFor guys with 10-twist barrels, try out the new Berger 87gr VLD. It was expressly designed to work great in the 1:10″ twist barrels. Forum member Mark Schronce reports that this bullet is extremely accurate and can be driven fast. It has an 0.412 G1 BC. Note: The new 87gr VLD, product #24524, is hard to find on the Berger website, but it IS available. Berger calls it a “hunting bullet”, but it works great on paper also. MidwayUSA has the 87-grainers in stock as item #77854.

▪ Pure Accuracy — If you are looking for bughole accuracy out of your 6BR, try the Berger 80gr FBHP ‘Match Varmint’ bullets (item #24321). Many folks have reported these bullets will shoot in the ones and low twos, even in 8-twist barrels. For 100- to 200-yard distances, these bullets are hard to beat for pure accuracy. Beyond those distances, you’ll want something with a higher BC. We’ve had good luck with the Berger 80s pushed by Vihtavuori N135, and IMR 8208 XBR.

▪ C.O.A.L. — Bullet seating depth is very important. You should get the Hornady (Stoney Point) O.A.L. Gauge (shown below). This will let you discern the OAL at which the bullets just contact the rifling. The trick is tapping gently on the stick. (Get a wood dowel as the bullet can get stuck if you tap a little too aggressively.) With some practice, measuring is quick and you can get repeatable measurements of your distance to lands within .001-.002″.

Hornady OAL gauge

A good starting point for the Berger and Lapua 105s is about .010-.015 IN the lands and then work back. Each barrel is different, but about .010″ in the lands works for many folks. One guy I know started at .012″ in the lands with Berger 105s, adjusted his load up from 30.0 to 30.4 Varget, and within an hour he was done with load dev — the gun was shooting in the low 2s. He went out and won his first match with that load the next day! With the Sierra 107s you might want to start .020″ out of the lands.

▪ Seating Die — We recommend the Wilson Micrometer Seating Die. The adjustable top makes it really easy to play with seating depths. Keep in mind, however, that moving 5 hash marks on the die may not give you exactly .005″ seating depth change — it will be close, but you should measure and write down the actual base to ogive length. FYI, I measure base to ogive of every loaded round. Occasionally you’ll find a bullet that ends up seated a little long or short.

NOTE: The fit of the 6BR Wilson seating die is very tight. You may have difficulty getting a fired case into the die if you do not full-length size the case first. Even with FL-sized cases, there may be a vacuum fit that makes the loaded round a little hard to remove. If you can’t easily extract your loaded round, try lifting the entire micrometer head and attached stem. This can release the vacuum so the case can slide out easily (unless there is a really tight fit). If that doesn’t work, here’s another trick — use the end of a Popsicle stick placed under the cartridge rim to lever the case out. I’ve found that the “working” end of a metal spoon works well too, but be careful not to nick the bottom of the die.

Permalink Reloading, Tech Tip 4 Comments »
October 8th, 2012

Portable B&D Workmate Reloading Bench

portable reloading benchA while back, we featured a portable reloading bench built on a Black & Decker Workmate. That proved a VERY popular do-it-yourself project so we’re showing it again, in case you missed it the first time.

Texan Robert Lewis made himself a great portable reloading bench from plywood mounted to a Black & Decker Workmate. The bench, roughly 22″ x 19″ on top, folds up to fit easily in your car’s trunk or behind the seats in a pick-up truck cab. Four recessed bolts hold the wood top section to the collapsible B&D Workmate.The sides and back of the unit are attached to the base with small nails. There is a small shelf (also nailed in place) which can be used to clamp a powder measure or hold a scale. Shown in the photo is a Harrell’s Benchrest measure and Harrell’s single-stage “C” press.

Click for Larger Photo.

The whole unit can be built for about $65.00 with pine, or $80.00 with oak (as shown). Robert explained: “The Workmate was $40. If someone bought a 2’x4′ sheet of 3/4″ oak plywood, I think it is around $30. Using pine plywood would be about half that. Fasteners were $3. Spar Urethane would be $5.”

Robert told us: “I used a couple ideas I found on the web. The Larry Willis website gave me the idea to use the Black and Decker Workmate as a base. I found the Workmate on sale for $40 and the top is made from oak plywood I had in my shop. I sealed the wood with three coats of Spar Urethane. The whole thing folds into a nice package for transportation to and from the range.”

Editor’s NOTE: In the time that’s transpired since we first ran this story, the price of a Black & Decker workmate has gone up. However you can still pick a WM225 Workmate for under $60.00. Target is currently selling WM225 Workmates for $59.99.

Click HERE for FREE WORKBENCH PLANS.

portable shooting bench

Permalink Reloading, Tech Tip 8 Comments »
October 8th, 2012

TECH TIP: How to Speed Up Your RCBS ChargeMaster 1500

RCBS ChargeMaster 1500The RCBS ChargeMaster 1500 electronic powder scale and dispenser is the most popular product of its kind on the market. In our original Electronic Powder Dispenser Comparison Test, the ChargeMaster normally dispensed most kinds of powder faster than competitive units from Lyman and PACT. However, after the initial release of the ChargeMaster 1500, RCBS “tweaked” the software a bit to achieve more consistent charge-throws. This slowed down the process somewhat. Some owners have wanted to speed up their ChargeMaster. This IS possible with a relatively simple reprogramming. Most of the internal parameters of the Chargemaster can be modified, under guidance from the tech staff at RCBS.

Gunsmith and Forum member NAT Lambeth reports: “I thought My RCBS ChargeMaster 1500 Combo was fast enough. But I still called RCBS and asked for the programing changes to see if I could speed it up. It was a lot easier than I thought. My 1500 Combo was taking from 15-30 seconds to dispense the powder to the tenth of a grain. I reprogrammed the numbers and now it takes between 7 and 15 seconds to dispense to a tenth. This effectively doubled my loading speed. I only changed the HSB_A1, HSB_B1, and BSP_C1 settings.”

Key ChargeMaster Parameters with Default Settings
HSB_A1 (15.68) Grains under target weight to go from full to high speed
HSB_B1 (3.42) Grains under target weight to go from high to slow speed
BSP_C1 (1.08) Grains under target weight to go from slow to final trickle speed

Nat cautions that you should talk to a RCBS tech before attempting to re-program your ChargeMaster: “You will benefit from talking to the RCBS tech. I have now gone back and played with the numbers a couple of times. (The numbers given to me by the tech at RCBS were still a little conservative.) I think each machine may have its own likes and dislikes. If you get too aggresive with lowering your numbers it will over-throw your intended load.

Source for ALL the Parameters
There is an extensive discussion of RCBS ChargeMaster programming on the South Africa Hunting Rifle Shooting Assn. (SAJSV) Forum. In this SAJSV Forum ARTICLE, Jaco Brink lists virtually all the programming codes. Importantly, Jaco also provides the default values for various parameters. This is very important, because the ChargeMaster does not have a “return to default” option. Once you change any value, if you want to return to the original value you must enter it manually.

Jaco cautions: “I have to advise you to only make changes to your scale if you are confident to do so, and remember that there is not a ‘return to default’ setting in the scale. If all else fails return your scale to the default settings [I have listed].”

CLICK HERE for list of RCBS ChargeMaster Default Programming Values

Use a McDonald’s Straw to Reduce “Over-Throws”
Jaco Brink provided another useful tip to avoid “over-throws” (excess charge weight): “The RCBS employee advised me to take a McDonnell’s straw (because it is thicker than a normal straw), cut off about a half inch piece and put it into the tube where the powder exits. This caused the last part of an extruded powder to clutter less, and reduced the amount of overthrows dramatically.”

CLICK HERE for more ChargeMaster 1500 optimization TIPS.

Permalink Reloading, Tech Tip 9 Comments »
October 4th, 2012

TECH TIP: Diameters Vary Among Bullets of Same Caliber

Choosing the right-diameter bullet can have a big effect on accuracy in match rifles. “Wait a minute”, you might say, “doesn’t one simply choose a 6mm bullet for a 6mm barrel and a 7mm bullet for a 7mm barrel, what’s the big deal?” Well… it’s not that simple. Not all bullets of the same nominal caliber actually have the same true diameter. We’ve seen different-brand 6mm bullets vary by as much as a full thousandth (.001″) in diameter. We have seen undeniable evidence that a poor “fit” of bullet diameter to bore dimensions can result in a poor-shooting gun, even one with a high-grade barrel.

Conversely, if you find the bullet diameter you barrel likes, that may instantly improve your accuracy. The accuracy gain may be more significant than making changes to the bullet seating depth or even powder charge. The importance of bullet diameter is compounded by the fact that 6mm match barrels are available with both .236″ and .237″ land diameters. Some barrels prefer “fat” bullets while other barrels prefer “skinny” bullets.

Last year, Jason Baney measured 12 different sets of 6mm Match Bullets, including a couple different lots of the same bullet design. Interestingly, Jason did measure the “old” Berger 105 VLD, the new-generation Berger 105 VLD (first lot from the new die), and the “new, improved” Berger 105 VLD from the new die, after it was polished. Ten (10) Bullets were measured per type. Each bullet was measured three times (3X) around the largest circumference, normally where a pressure ring would be located (some bullets have a pronounced pressure ring, others do not). NOTE: We provide the numbers from Jason’s tests, but remember that bullets from different production runs may have slightly different dimensions. You should augment our findings with your own measurements from later-produced bullets.

6mm bullet diameters

Download this CHART as an MS Word Document.

The first two columns of the chart show the smallest and largest bullet diameters measured for each 10-bullet sample. The third column shows the extreme spread over each 10-bullet set. Note, these numbers are NOT averages, but represent the “low” and “high” diameters for each set. (FYI: Jason noted that while the Lapua Scenars were very consistent, an earlier 2005 “JEVDAK” lot had smaller meplats than 2007 and 2008 lots.) A Mitutoyo Micrometer was used, zero-checked for each bullet.

Permalink Bullets, Brass, Ammo, Reloading, Tech Tip 3 Comments »
September 30th, 2012

Web Buyers Guide and Gun Talk Radio Provide Gun Safe Info

Liberty Gun Safe Gunsafe rebateIt seems like every week, readers send us questions about gun safes. They want to know how much they should spend and who has the best deals. They also have numerous hardware questions, such as: “What’s better — digital keypad vs. rotary (spin dial) lock?”, and “Should I look for a safe with internal or external hinges?”. We answer many of these questions in our comprehensive Gun Safe Buyers Guide, which is definitely worth reading.

After reading our Gun Safe Buyers Guide, if you still have more questions, tune in to Tom Gresham’s Gun Talk Radio Show this Sunday, September 30th. On this Sunday’s broadcast, Liberty Safe’s Jamey Skousen talks about the important features of gun safes and security vaults, and Skousen explains what to look for when shopping for a safe. As an added bonus, Liberty Safe is offering a special rebate in connection with this Gun Talk broadcast. To save money on your next safe, click the graphic at right to download the rebate form. Or, go to LibertySafe.com and click on the photo of Tom Gresham in the upper right hand corner. On a $1500.00 Liberty Safe you’ll get a $50.00 instant rebate plus a $50.00 mail-in rebate, for $100.00 total savings.

Gresham Gun Talk RadioIn its 18th year of national syndication, Tom Gresham’s Gun Talk Radio airs live on Sundays from 2:00 pm to 5:00 pm Eastern. Gun Talk Radio runs on more than 135 stations, plus XM (Ch. 165) Satellite Radio. The Gun Talk Minute on XM also airs on XM 165, 166, 168 and Fox Sports every day. Gun Talk shows can be downloaded as FREE Podcasts via Gun Talk’s Podcast Archive.

Permalink Hot Deals, Tech Tip 2 Comments »
August 30th, 2012

Mirage Shields Tame Barrel Heat for More Accurate Shooting

Even if you don’t shoot competitively, you can benefit from having a mirage shield on your barrel. The shield helps prevent barrel heat from “cooking” the air in front of your scope, which can distort the view you see through the optic. Barrel heat creates a mirage effect that can blur the target image and actually shift your apparent aiming point up and down. Competitors know that a mirage shield helps them shoot smaller groups and better scores. Mirage shields can likewise benefit Varmint shooters on those hot summer groundhog and prairie dog expeditions.

Make a Mirage Shield from Discarded X-Ray Film
Forum member Fabian from Germany, whose Sako 6BR was featured as a Gun of the Week, has devised a clever and inexpensive mirage band option. Fabian is a radiologist by trade. He notes that many X-ray machines require a daily test film for calibration. These are normally just discarded in the trash, so you can get them for free.

mirage shield

Fabian explains: “I’m a radiologist, so I handle medical x-ray films every day. Modern X-ray machines use laser-based printers and they need to print a test-film every day. One x-ray film is about 43×35 cm (16.9″ x 13.7″). Made from polyester, the films are very stable and only 0.007″ inches thick. They are light-weight, semi-transparent, and very stable. Using normal scissors, you can easily cut four mirage shields from a single sheet of film. Then glue on some velcro to attach to your barrel. Try it, you will not be disappointed.”

mirage shield

More Do-It-Yourself Ideas
Other forum members have made mirage shields out of common, inexpensive materials such as old venetian blinds, thin plastic edging strips, and even cardboard reinforced with strapping tape. There’s no “magic material”. However many shooters have found that wider shields (extending well past the barrel sides) work better than narrow shields, particularly in hot weather.

Mirage Shields with Printed Designs
If you prefer to purchase a mirage shield, Shotmaster 10X offers a wide variety of shields starting at just $5.00 for a plain white 18″ shield. Patterned shields (including camo designs) are priced by length: $8.50 (18″), $9.50 (20″), $11.00 (24″). All Shotmaster shields come with two (2) velcro patches with self-stick adhesive.

Shotmaster 10X Mirage Shield

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