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April 20th, 2007
 Reader Richard H. just tested his new CED M2 Chronograph, one of the first units in the country. This is an all-new design with many upgrades over the previous CED Millenium model. Clock speed was boosted to 48 mHz, expanding the measurable velocity range to 7,000 fps. Memory storage has been expanded 500%. You can now have up to 500 speed readings per string (and as many as 500 strings). CED claims: “Expanded digital chip design now gives the CED M2 the ability of reading velocities at much lower light levels. On clear days, this means the ability to chronograph from early morning till almost sunset.” If this claim is true, the CED M2 would definitely out-perform rival PACT and Shooting Chrony designs in marginal light conditions.
We’ve found that, with most chronographs, the biggest problems are confusing controls and keypad sequences that are hard to remember. CED has addressed that with the new machine. The $199.00 CED M2 Chronograph features single function string removal (something we wish the Shooting Chrony had), and the M2 offers “one touch” calculation of the average of the three highest velocities in a string. Another major (and much appreciated) improvement is the addition of a USB interface. That offers simple “plug and play” compatibility with laptops and home PCs. USB connectivity will make it much easier to download Chrono data into the updated CED Data Collector software. For more info, contact Competitive Edge Dynamics, CEDHK.com, (610) 366-9752. Right now the CED M2 is back-ordered, but a new shipment is arriving in 2 weeks and M2s should be available by mid-May at Brownells and MidwayUSA.com.
Richard tells us: “I’ve been frustrated for a long time with my inability to get my extreme spreads below 30-50 fps and have wondered if my bargain-basement Chrony F-1 might be part of the problem. Well, after I got my Denver Instruments MXX-123 last month, the powder scale was no longer a credible culprit, so I went shopping for a new chrono. This is what I found. Initial results (only three 5-shot groups so far) suggest that ES with the CED M2 is only half of what the Chrony measured. In the Chrony’s defense though, it is surprisely good for something that costs less than half as much (also more convenient and more portable).” If anyone in the Sacramento, CA area has an Oehler Chrono, Richard would like to do a 3-way comparision test with the CED, Oehler, and Shooting Chrony. We’d all be interested in the results. Contact Mailbox@6mmBR.com and we’ll put you in touch with Richard.
April 8th, 2007
 Most rear sand-bags (from Edgewood, or Protektor, or SEB) are optimized for use on the bench with low-profile stock designs like the McMillan Edge or Kelbly Klub. If you use these bags when shooting from the ground F-Class style or with bipod, you may find the rifle is too low to the ground for comfort. Yes you can suck in your belly and crank down your front rest, but it makes more sense to elevate the rear bag. Jason Baney has a simple solution that costs under $4.00 in materials.
Get a small 12″x12″ section of 1″ thick plywood and trim it to fit the base of your bag, leaving maybe 1/2″ extra on all sides. Then get some rubberized, waffle-pattern GRIP-IT shelf-liner from your local home improvement center. Alternatively, if you want a more rigid base (with less ‘give’) for hard, flat ground, use high-durometer unlined Neoprene, available from industrial supply shops. Glue a layer of shelf liner or Neoprene on the bottom and top of the plywood. This will give good grip on your shooting mat and provide a stable, non-slip surface for the base of your sandbag. If you need more elevation, just use a thicker piece of wood, or sandwich two pieces together. If you have a heavy recoiling rifle and need a riser with more mass, put a metal plate (same dimensions) between the plywood and the bottom layer of rubber shelf-liner/neoprene. If you want a bag riser without the work of trimming and glueing, Dave Dohrmann sells high-durometer Neoprene riser pads in 1/2″ through 1″ thicknesses, starting at $25. Call Dave at 864-884-0155 or email dbugholes[@]aol.com. With textured surfaces top and bottom, Dave’s heavy pads work equally well to elevate your bag on the bench.
April 4th, 2007
Chris Long (Techshooter) has produced a detailed article on how to form 260 Remington Ackley Improved Cases. With nice, big photos illustrating the process, Chris explains how to form your cases, using either bullets, or an inert filler (no projectile). Chris also covers how to place a false shoulder in the cases prior to fire-forming. This creates a slight crush-fit, helping the shoulders to form more reliably, with fewer split necks. Chris formed cases using both Remington-brand 260 Rem cases, and Lapua .243 Win cases necked up to 6.5mm. Chris discusses how doughnuts can form when necking-up .243 Win brass and how doughnuts can interfere with bullet seating. Chris then explains how to remove the doughnuts using inside neck reaming. Click HERE to read article.
April 4th, 2007
On AccurateShooter.com’s Ballistics Page, you’ll find the excellent JBM Ballistics program. This not only calculates bullet trajectory with great precision, but will also output clicks so you can create your own “come-up” chart to keep with your rifle. In addition, you can download FREE versions of Pejsa and Point Blank ballistics software. Point Blank is also a database that stores your favorite loads. Pejsa, an Excel spreadsheet with a sophisticated drag formula, is a great choice for VLD bullets (.Zip version). We normally store loads in Point Blank (resident on the computer), and generate come-up tables with JBM or Pejsa (for VLDs).
Here are links to more FREE Ballistics programs:
Big Game Info Ballistics Calculator
NFA Ranging Ballistics Computer (Excel file Download)
Federal Cartridge Ballistics (for loaded ammo)
Remington Shoot Ballistics Software (Software Download)
Shooting Times Ballistics
(Choose caliber for sample ballistics by bullet weight.)
April 2nd, 2007
 Credit Joe Friedrich for this simple yet effective accessory for your benchrest rifle. Joe shoots a .22LR with a tuner. When he added weights to his tuner, he found his rifle no longer balanced well. He wanted to add a substantial amount of weight in the rear without drilling holes in the stock. He also wanted the weight to be removable, and easily placed on another rifle in his stable.
At a local sporting goods shop Joe found a 1.5-lb ankle weight that comes in a padded, tubular elastic cover. It’s like a 1.5-lb sausage in a soft, stretchy nylon cover. (Imagine a really fat, heavy bungee cord). Joe simply attached a plastic zip tie at the end to make a loop that fits perfectly over his buttstock. To “tune” the rifle’s balance, Joe just slides the ankle weight fore and aft on the stock. Yesterday we tried it on a variety of different BR stocks (including a McMillan Edge) and it worked perfectly. This is a great invention, and would work with sporter rifles and ARs just as well. Click HERE for big photo.
March 30th, 2007
There has been much interest in Ultrasonic case cleaning. Here are two tips to achieve the best results:
De-gas the Solvent Before Adding Brass
One of our readers, Eddy M. in Glasgow, Scotland writes: “I have read a couple of articles recently about ultrasonic cleaning of cases and not one has mentioned de-gassing the cleaning liquid before starting to clean items. As an engineer who travelled around for ten years servicing ultrasonic tanks I would like to point out that the cleaning liquid when first put into the tank has invisible disolved air bubbles in it which will absorb ultrasonic energy until the liquid de-gasses. (10 minutes in a powerful industrial tank–longer in a small hobby tank). You must let the tank run on its own for 20 minutes on the first use of the liquid to allow this to happen. Only after the new liquid or re-introduced liquid has been de-gassed will the tank give good results.”
Apply Dry-Lube Inside Case Necks
Jason Baney has 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.
March 30th, 2007
There have been some questions on our Forum regarding the recommended procedure for flash-hole uniforming on Lapua 220 Russian (PPC parent), PPC and 6BR cases. The factory spec on these cases is 1.5 mm (.059″) for the flash hole. In the past, we found it was normally not necessary to touch the flash holes on Lapua PPC/BR cases. However, with recent lots, a few cases per box will have a little sliver of brass that may obstruct part of the flash hole. It is advisable to remove this–but you don’t want to enlarge the rest of the flash hole in the process. There are a lot of tools on the market to do this job, but we’ve found that some will actually enlarge the flash hole to as much as .067″ which is not good.
The problem with the Lapua brass is a little “quarter-moon” of brass that forms on one side of the flash hole. The objective is to knock that out without increasing the diameter of the flash hole. A simple way to do this is to simply punch out the hole using a #53 or 19/32 pin drill bit in a Pin-Vise (below, about $5). The #53 bit measures .0595″ while a 19/32 is .059375″. You can find pin vises and bits at hobby stores or eHobbyTools.com.
Sinclair Int’l has two flash-hole tools, one that works from the outside (DB 07-3000) and one that works from the inside (DB-2000). The DB-2000 is spec’d to ream a .060″ hole. Depth of cut is set with a conical collar that indexes on the case mouth. Note, this tool can also cut a chamfer or funnel on the top edge of the flash hole. We recommend you set the depth stop so you only clean up the flash hole and do NOT cut a funnel. We also recommend you actually measure the cutter tip to ensure it is the correct diameter–some examples have been oversized–the same problem we found with other brands.
Both Forster and Redding supply dies with a .057.-058″ decapping pin for use with BR and PPC cases. However, the “normal” small decapping pin on some other dies is .0625 (1/16″). Sinclair makes a second tool, DB 07-3000, that cuts to this diameter (.0625″), going in from the bottom side.
Sinclair explains: “This tool was designed specifically to ream small flash holes (.060″) to exactly .0625″. It enlarges the holes just enough for the die maker’s decapping pins to go through without getting stuck… This 3-piece tool has a stainless steel guide that centers the reamer in the primer pocket from the outside.”
Which tool should you use? We prefer to keep the flash-hole as close to factory spec as possible. However, plenty of BR matches have been won with cases reamed to .0625″. The important thing is to remove whatever obstruction may exist in the brass, and make sure all the cases are uniform, whatever hole size you prefer.
March 25th, 2007
 Many die manufacturers use locking rings that require a set-screw to be tightened down on the die threads. That can, eventually, deform the threads. There are some work-arounds, such as placing a piece of plastic between set screw and threads, but there is a better solution. We recommend upgrading your dies with Hornady’s cross-bolt style Sure-Loc Rings. These are made of steel with flats machined in the sides. Here are Sure Loc user reports from MidwayUSA: “Split ring design works better than rings with a set screw that tightens against the die threads. Wrench flats are a big plus–get these rings… and never struggle with your dies again.”-M. Masuda. “All die lock rings should be of the cross bolt design… this ring won’t damage the threads on the die body like factory RCBS and Redding lock rings do.” T. Little. The Hornady Sure-Loc Die Locking ring (mfg. #044000) is available from most major vendors for under $4.00 ($2.99 at PrecisionReloading.com).
March 25th, 2007
 We’ve learned that, when necking down a 6.5×47 Lapua case to 6mm, it’s best not to simply run the brass into a 6-6.5×47 full-length sizer. Reader “Fireball”, who has worked with both a 6-6.5×47 and a 22-6.5×47, offers this tip: “You don’t want to bring the 6.5mm case all the way down to 6mm in one step–it’s too big of a jump. First, to smooth entry, you should run a 6.5mm expander in the case mouth, and chamfer the outside of the case mouth–be sure to remove all burrs and smooth the case mouth. Apply some lube to the neck. Then, if you have a bushing for a .257, put that in a 6BR bushing neck die, and run the case up. Alternatively, you can use a Redding 6BR body die. The body die will funnel the neck down about half way. Body dies are pretty inexpensive ($22.49 at MidwayUSA, item 458797). After running the brass through the 6BR body die, then you can run the case into the Forster 6-6.5×47 Full-length sizing die. The Forster die is excellent–it sizes a no-turn neck just about perfectly, so long as you do an intermediate step first.”
March 24th, 2007
TechShooter has been campaigning a 260 AI with great success. At the Cascade 600-yard range, he recently shot a 600-34X using the new 130-grain Bergers. However, like this editor before him, TechShooter has had signficant issues with doughnuts forming in necked-up Lapua .243 Win brass. In the hopes of avoiding the doughnut problem altogether, TechShooter has been testing Remington 260 brass. Chris reports: “I didn’t like the hassle of the inside neck-reaming the Lapua brass, as well as the possibility that this process could cause excessive runout. I measured the neck-wall thickness variation of Remington brass using the test fixture shown below. Only those cases that were under .0015″ total variation were selected, the rest were set aside. Only about 15 brass of the 500 were outside this tolerance, with the vast majority under .001″.” Chris concluded, and we agree, that the Rem brass is a viable alternative for .260 Rem or .260 AI shooters. Chris tells us: “I am using the Remington brass exclusively now. The Remington brass is of very good quality, at least the batch of 500 that I just got.”
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