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March 21st, 2007
 When using the Stoney Point type OAL gauge (now sold by Hornady), we sometimes get a bullet stuck in the rifling. This can also happen with a squib load or when extracting a round with the bullet seated hard in the lands. You can use a cleaning rod or a wood dowel to tap out the bullet, but a brass drop rod will do the job faster and easier, with less risk of nicking your crown.
You can make a drop rod yourself from brass or bronze rod. Just make sure to smooth over any burrs or rough spots on the ends. Or just order the new brass bullet drop rods from Sinclair Int’l. You drop the Sinclair Rods down the barrel from the muzzle end with the rifle standing upright. Sinclair Bullet Drop Rods are made of brass so they will not harm the rifling in your barrel. Each $10.50 set consists of two Drop Rods that will handle .20 up to .416 caliber. Remember, for safety sake, Drop Rods are never to be used to dislodge live or loaded rounds! Always remove the Drop Rod from the barrel before chambering another round!
March 19th, 2007
Most shooters have some understanding of basic ballistics principles. But you may be surprised by how much more there is to learn. Bryan Litz, a missile design engineer for the U.S. Air Force, explores some of the more fascinating (and esoteric) issues of bullet ballistics on his Long Range Shooting web page. Topics include Bullet Design, Ballistic Coefficient Testing, Gyroscopic and Coreolis Drift, and the effects of Meplat Trimming. We hope to collaborate with Bryan on future articles concerning bullet design and ballistics. It’s not often, after all, that a dedicated shooter is also a bonafied rocket scientist. You’ll enjoy Bryan’s site–we suggest the article on Meplat Trimming for starters.
March 13th, 2007
 Ace long-range shooter John Whidden has introduced a new bullet-pointing system that promises to improve the B.C. of match bullets significantly. John tells us that “tests have shown these bullets to have a typical B.C. increase of about 35 to 40 points as compared to bullets right out of the box,” and at 1000 yards, “we usually see them impact about 1-1.5 MOA higher. We have reports of .224 80-grainers shooting 2.5 MOA higher just by pointing.” The proof is in the shooting. Our own Jason Baney has experimented with Clinch Rivers that had the tips pointed up (not by John though). Jason reports: “Shot round-robin, with my 6BR, 5-shot group centers were 18″+ apart vertically. In other words, the pointed bullets flew 1.75MOA flatter to 1025 yards. This number has been repeated in matches at Williamsport.”
What about trimming meplats instead? Well, that does make bullet to bullet B.C. more consistent, but, unfortunately, it reduces the B.C. somewhat at the same time. Pointing the bullet tips with a special pointing die raises the effective B.C. and makes the B.C. more consistent by taking the ragged edges off the meplats. For more info, call John Whidden at (229) 686-1911 or visit WhiddenGunWorks.net.
March 11th, 2007
Too often we rely on luck and “voodoo” to pick the best rimfire ammo. Shooters resort to testing batch after batch of ammo in hopes of finding the “holy grail”. What we’ve learned, in testing a 17 Mach 2, is that some of the accuracy issues with rimfire ammo CAN be quantified, and the “mystery flyers” can be explained. Using a Nielson Brothers Concentricity Gauge, we tested lots of 17 Mach 2 ammo from Eley and CCI. Most of the rounds had run-out of .002″ or .003″. However, we found some rounds had run-out as high as .009″ (See video). That’s shocking. A cartridge with .009″ run-out is a guaranteed flyer that will kill your group. Interestingly, when cartridge run-out was .004″ or higher, you could clearly see the bullet tip was way off-axis–confirming the results of the gauge. Using the Nielson Gauge we could quickly sort bullets in .001″ increments. For match purposes, you should cull anything worse than .003″ run-out. By sorting for .0015″ run-out or less, we were able to reduce our average group size by 30%. More importantly, we eliminated most of the unexplained fliers that were landing well outside the main group. The Nielson Gauge works for both 17 Mach 2 and 22LR. And, with different inserts, you can measure 17 HMR and 22 magnum rounds.
Click to Watch Rimfire Run-out Test Movie (1 mb .wmv file):
March 7th, 2007
When we ran our blog item mentioning that David Tubb has forsaken Moly in favor of Boron Nitride, people took notice. Many folks asked how they could get their bullets coated. David told us that his company, Superior Shooting Systems, will offer bulk boron nitride bullet coating, if you send in a minimum of 1000 bullets. Price is not set yet, but David expects the cost to run about $50 per thousand. To order call (806) 323-9488. Please note, David is NOT selling boron nitride supplies or kits for do-it-yourselfers at this time.
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