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August 1st, 2007
Hodgdon has produced some interesting tables that show how changing temperatures affect the performance of various powders. While most powders generate higher velocities as temperatures rise, it is interesting to note that some powders experience much smaller velocity shifts than others. Here are two charts prepared by Hodgdon:
Extreme Velocity Spread For Temps Between 0°-125°
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Cartridge: 30-06
Case: W-W
Primer: WLR
165 gr. Hornady SP |
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Cartridge: 300 Win. Mag.
Case: W-W
Primer: WLRM
180 gr. Sierra Boat Tail SP |
To learn more about how ambient temperature (and primer choice) affect pressures (and hence velocities) you should read the article “Pressure Factors” by Denton Bramwell. In that article, the author uses a pressure trace instrument to analyze how temperature affects powder performance. Bramwell’s tests yielded some fascinating results.
For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per degree F for the Varget load….If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.“
August 1st, 2007
 MidwayUSA now has Ramshot Hunter on sale for $9.99 per pound, item # 920960. That’s $5.50 off the regular price of $15.49 per pound. Ramshot Hunter is a quality ball powder that meters easily, with a burn rate similar to H4350, Norma 204, or Alliant Reloader 19. It is a good choice for the 22-250, 6-6.5×47, 6XC, and the short magnum cartridges. Ramshot Hunter’s small spherical particles pack tightly, offering good velocities in cases that are short on capacity. If you’ve run out of room with H4350, consider Ramshot Hunter. The sale ends August 31, 2007.
August 1st, 2007
James Mock reports that Joe Krupa shot his way into the Benchrest Hall of Fame at the IBS Nationals now underway in St. Louis: “Joe used his great shooting Jay Young rail gun to win three more Hall of Fame points. These three points gave him 11 total. That means that he is our newest member of the BR Hall of Fame. Congratulations Joe.” Joe’s Agg for the Unlimited Class 200-yard Heavy Bench gun was .2866, while his Grand Agg was .2934″. For more information, read this thread on Benchrest.com.
July 31st, 2007
On July 30th, internet auction site eBay announced it will change its current policies regarding sales/auctions of gun parts and reloading components. Currently, one cannot sell firearms on eBay, nor live ammunition, nor a variety of “black-listed” gun accessories such as high-capacity magazines. Now, eBay will prohibit the sale of “any firearm part that is required for the firing of a gun.” This will include brass, bullets, and barrels. The new policy was announced by Matt Halprin, eBay Vice President:
“In mid-August, we will be updating our Firearms, Weapons and Knives Policy to place more restrictions around gun-related items. Once these changes take effect, we will prohibit listings of any firearm part that is required for the firing of a gun. This includes items like bullet tips [sic], brass casings and shells, barrels, slides, cylinders, magazines, firing pins, trigger assemblies, etc. Please read the Firearms, Weapons and Knives Policy for more details on our current policy.
As you may know, eBay does not allow the listing of any items which are regulated by individual states or the federal government; however, there are still a large number of firearm-related parts that are legal and are widely available in retail stores. These items have also historically been allowed on eBay.
After learning that some items purchased on eBay may have been used in the tragedy at Virginia Tech in April 2007, we felt that revisiting our policies was not only necessary, but the right thing to do. After much consideration, the Trust & Safety policy team – along with our executive leaders at eBay Inc. – have made the decision to further restrict more of these items than federal and state regulations require. This new update… brings our policies in the U.S. and Canada in closer alignment with our existing policies in other markets around the globe.”
July 31st, 2007
 The International Benchrest Shooters (IBS) Nationals kicked off July 30th in St. Louis. The event, which draws top 100/200 yard shooters from around the nation, continues through August 4th. Hosting the Nationals this year, is the Benchrest Rifle Club of St. Louis, 2045 Kohn Rd, Wright City, Missouri.
IBS 100/200 Score Nationals are also held this month, August 18-19, at the Canastota Conservation Club, Warners Road
Canastota, New York. The IBS 200/300 Score Nationals follow a month later, September 22-23, at the Thurmont Conservation & Sportsman’s Club, 11617 Hunt Club Rd., Thurmont, Maryland. For more info about these IBS events, visit the IBS website and click “Featured Events”.
Shown below are the top shooters from last year’s 2006 IBS 100/200 Group Nationals held at Canastota. Top row (L to R) are Rob Sarbrough, Mike Ratigan, Joe Krupa and Russ Boop. Wayne Campbell is in front. Photo courtesy IBS.
July 30th, 2007
 ShooterReady.com offers an excellent computer simulation that lets you “shoot” three different calibers at virtual ranges out to 2000 yards–complete with sound effects and realistic scenery. You view the target through a 10-20x zoom scope and adjust windage and elevation as with a real scope. A FREE Online Demo is available that lets you practice with a 175gr .308, and also Windrunner .338 and .50 BMG. Atmospheric conditions and range distance change with each stage, so there is plenty of challenge. Warning–if you’re at work, this can be addictive once you get the hang of it.
 You can practice Mil Dot ranging on 3 targets: A 12″ X 12″ swinging plate, a 30″ X 18″ knock-down plate, and a regulation 72″ X 19″ knock down plate. Each caliber has 70 range exercises, plus an advanced stage with 25 timed hold-offs, and moving targets.
The CD also includes “Interactive Classrooms” that teach you how to use Mil-Dot scopes and how to use a range card. The presentation on reading Mils and calculating target distances is very well done. It is much easier to learn interactively than by just reading a static manual. Below is a screenshot from the Mil-Dot Ranging “Classroom”.
Trust us, you can learn a great deal from the Free Demo. This is not just a shooter video game. The demo offers a variety of scenarios–enough to keep you occupied for quite some time. If you want to learn more, the full CD, with hundreds of scenarios, and five bonus stages, costs $39.95 from ShooterReady.com.
July 30th, 2007
 In conjunction with the 100th anniversary of the NRA National Rifle and Pistol Championships at Camp Perry, NRA President John C. Sigler (at right) is initiating a Competitive Shooting and National Championships Endowment.
An endowment is a permanent fund or savings account that produces investment income. The permanent fund is never touched – only a portion of the fund’s interest is used for qualified programs. The balance is then reinvested to ensure the fund’s growth, thus providing a source of income in perpetuity. “Competitive shooting is at the core of NRA’s mission,” Sigler commented. “This endowment will help provide permanent funding necessary to ensure continued operation and growth of national-championship level competition, and enhance shooting participation wherever feasible.”
“NRA sanctions about 10,000 tournaments a year and conducts more than 50 National Championships,” Sigler continued. “It is essential that we not only protect our current programs but expand the opportunities for Americans to find new, fun ways to exercise their Second Amendment rights.”
Commenting on the endowment, Mike Krei, NRA’s Director of Competitive Shooting, said, “This initiative is a major step toward securing the long-term growth of NRA competitive shooting events. Serious competitive shooters who want a way to give something back to the sport in perpetuity will find no better option than this endowment.”
To donate to the NRA Competition Endowment, contact Frank Cerutti, Director of NRA Strategic Giving, at (703) 267-1571 or fcerutti@nrahq.org. Donations to some programs within this endowment may qualify as charitable gifts for tax purposes. Gifts may be made in cash, stocks or other assets, and pledged over time or as an estate gift.
July 29th, 2007
 What is the most-used piece of equipment on this editor’s reloading bench? No it’s not my Rock-Chucker press, or even my calipers. The one item in near-constant use is a small, folding magnifying glass. Mine folds into a square case and offers 4X viewing with an 8X bifocal insert. With this handy tool I can inspect case mouths for burrs, check primer pockets, and look for flaws on bullet jackets. I also use the magnifier to see rifling marks on bullets seated into the rifling, or check my bolt for galling. The number of uses is nearly endless.
Folding magnifiers are so handy yet inexpensive that you should own a couple spares (including one in the range box). I bought my magnifier in a book-store, but you can also find them on the web at Edmund Scientifics and WidgetSupply.com starting at just $1.97.
July 28th, 2007
Lock, Stock & Barrel is currently selling Timney triggers at 25% off normal retail. Triggers are available for most popular actions including Browning, CZ, Mauser, Remington, Ruger, Sako, Springfield, and Winchester. We are impressed with Timney’s new Rem 700 “Tactical” trigger (item TM501T). This Rem Tactical trigger adjusts from 4 to 10 ounces pull weight. It features a knurled Anschutz-style vertical trigger shoe that can adjust for angle (cant) and length of pull. The trigger housing is machined from solid steel, and all contact surfaces are CNC-machined steel that has been hardened, surface ground, and polished. Timney’s Rem 700 Tactical trigger is now just $86.06 at LockStock.com. That’s a great deal. The same trigger sells for $134.95 on Timney’s Online Store, TimneyTriggers.com.
Timney also offers two new AR-15 triggers. The AR-15 Competition trigger is a true drop-in replacement for the standard fire-control system that uses your rifle’s original hammer/trigger pins. Timney claims the trigger module can be installed in ten minutes. It comes in 3- or 4-lb versions and features a crisp, one-stage pull. MSRP is $194.95, and a skeletonized version (shown below) retails for $234.95. Lock, Stock & Barrel does not list the new AR-15 trigger in inventory, but you can call for pricing, (800) 228-7925.
July 28th, 2007
Some of our forum members have observed issues with the Acculab VIC-123, an 0.001g precision electronic balance made by Sartorius. The two main complaints seem to be sensitivity to drafts, and instability of zero, causing weight read-outs to “drift” over time. We have seen the latter problem in less expensive scales such as the PACT. (Read PACT report).
 Forum member Ronemus, who lists his profession as “instrumentation scientist”, offers the following advice:
“It is necessary to isolate the scale from drafts and vibrations. Laboratory scales with this sort of resolution (.001g) generally have a housing around the pan with sliding doors for access and vibration isolators in the feet. Those scales cost thousands of dollars, and some features must be cut to reach a price we’re willing to pay. Unfortunately, the instruction manuals accompanying our scales generally aren’t very good at spelling out the steps necessary to have then operate to our satisfaction.
A small draft (one you can barely feel) can easily shift the reading a few tenths of a grain, so some sort of enclosure is needed. I use a cardboard file box with one end cut out, so 3 sides and the top remain, and that’s good enough for 0.1 gr (6 mg) stability; however, that may not be sufficient for 0.01 gr.
For stable zeros it’s necessary to warm up for at least a few hours (they’re generally left on continuously to avoid drift) and keep the room temperature fairly constant (within a few degrees).
Inexpensive scales are also susceptible to electrical noise, either riding the power line or through the air. Power line noise can be eliminated with a good filtered power strip (I recommend a Tripp-Lite Iso-Bar), not just a surge suppressor. Cordless and cell phones, fluorescent lights, wireless computer networks, baby monitors, etc. can cause problems at short range, so they should be kept away from the scale as much as possible.”
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