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July 20th, 2008
Earlier this week, German Salazar tested the new Alliant Reloder 17 (RL17) powder, checking for velocity and pressure. Using the 6XC cartridge, German found that RL17 could drive Sierra 107gr MKs over 200 fps faster than could H4831sc. RL17 likewise delivered big velocity gains with 115gr Bergers in the 6XC.
Salazar Shoots 600-39x with Reloder 17 at 500 Yards
On July 20 (this morning), shooting at the Phoenix Rod & Gun Club, German confirmed that RL17 can deliver real-world, match-winning accuracy. Shooting a 500-yard prone High Power match on the NRA MR65 target, using iron sights, German posted a very impressive 600-39X score. The three relays were shot with Sierra 107s, using three different loads of RL17 in progressively “hotter” increments: 40.6 grains (3215 fps), 41.2 grains (3290 fps), and 41.8 grains (3311 fps). Salazar shot 200-14X with the low load, 200-15X with the middle load, and 200-10X with the hottest load. German felt the middle load was the most consistent. (NOTE: these loads are all with moly-coated bullets. You should reduce the load by at least one full grain for “naked” bullets”.)
 German explains: “Ask any high power shooter and he’ll tell you 600-39X is quite an achievement with iron sights on the new (smaller) MR65 target at 500 yards. I can say with assurance now that this powder will shoot accurately in the 6XC. Last week, using H4831sc, shooting the same 6XC rifle, at the same range, with the same course of fire, I shot a 598-29x. I do think Reloder 17 helped me shoot a higher score this week, with 10 more Xs. The extra velocity afforded by RL17 reduces wind drift considerably, and the elevation held very consistently, particularly with the first two loads.”
Even at the hottest load, 41.8 grains (3311 fps) of RL17, German did not observe sticky bolt lift or other notable signs of pressure. So far, then, what we’ve learned about Reloder 17 is “all good” — in the appropriate cartridge, it will boost velocities dramatically, and it can deliver competitive accuracy in High Power competition.
July 20th, 2008
Last week, the third annual Southern California Precision Rifle Competition (SCPRC) was held. This match takes place each year in July at the West End Gun Club, 20 minutes west of San Bernadino, CA. Match director Mark Archuleta, aka “Spaniard”, ran a great match, with a diverse and challenging course of fire. Mark reports: “This was our third SCPRC, and we had 34 shooters from all over the US.” Mark posted a match report in our FORUM with lots of photos. CLICK HERE to read Mark’s full report. Below are some pictorial highlights from the Match, with Mark’s commentary:
Vu Pham from Nor-Cal, shown below, hit both his cold bore shots on day 1 & 2. This year’s Day Two cold bore shot (CBS) reprised our 2006 CBS. There was a 3.5″ Clay pigeon set at about 325 yards, with roughly a 10° down angle. In 2006, 7 out of 22 shooters made the hit, this year 12 out of 34 shooters made the hit. Some folks don’t think that the 10°-15° slope makes a difference, but it does.
Below Phil demonstrates textbook bipod shooting: working the bolt, maintaining a solid cheek weld and keeping an eye on the next target. Good job Phil. [Editor’s Note: the “pucks” on the bipod legs are “PodPaws” from Zephyr Dynamics]
One of the stages was shot from a squatting position with rifle supported by saw-horses. This stage obviously favored the shorter guys.
The match included timed stages. The challenge was how to record times for multiple shooters. I purchased a timing system and did some modifications to it so each shooter had his own stop button. It worked great and I could shoot whole teams all at once. This made the lines move very fast. It’s will be a part of all my future matches, local and not so local. Below, just like on Jeopardy, Scott Cochran stops the clock.
At the request of Kurt Stone (LV Steel Targets), a standing stage was added. It’s not easy to shot a heavy tactical rifle off-hand! Here, representing the United States Marine Corp., is SSgt. Tony Palzkill — a real professional and a nice guy too.
July 19th, 2008
Alliant’s new Reloder 17 powder is the new “Speed King” in its burn-rate category. It promises to raise the velocity bar in many cartridges which work best with slow-burning propellants. Based on initial test results, if you’re using H4350, IMR4350, Reloader 19, Norma URP, or H4831 currently, you may find that RL17 can deliver dramatically higher velocities than other powders. CLICK HERE for FULL REPORT.
RL17 Boosts Speeds by 200 fps
The day after two pounds of RL17 arrived in Phoenix, German Salazar and Bob Jensen tried the new propellant in 6XC and .308 rifles, using an Oehler 43 chronograph equipped with pressure-testing equipment. The results were eye-opening. German was able to get 3311 fps using 107gr Sierra MKs in the 6XC. That’s roughly 200 fps faster than other popular extruded powders can deliver. With the 115 Berger, the 6XC topped 3200 fps, again a very impressive speed gain. Most 6XC shooters find that 3000-3050 fps is the most they can get with a 115gr bullet.
Speed by Design
What’s the secret to this new powder? First it’s made differently than most other propellants. Most extruded powders have an external coating on the kernels that governs burn rate. With RL17, the burn regulating compound saturates the entire kernel — it’s not just on the outside. The practical effect is that RL17 is able to maintain a higher energy level for a longer time — the energy output does not fall off as steeply as other powders. The other factor is density. Reloder 17 has fairly small kernels so it packs very tightly compared to H4831sc. As a result you can fit more powder (by weight) into the case.
Accuracy Testing Comes Next
German will continue his testing with other calibers — as soon as we can get more RL17 from Alliant. German also plans to start accuracy testing next week. If RL17 can deliver accuracy to match its high velocities, it looks like it would be a very good choice for the 6-6.5×47 Lapua, 6XC, 243 Win, 6mm Remington, .284 Winchester, and 30-caliber cartridges with the big (185+ grain) bullets.
Limited reloading data is available currently, but Alliant has distributed a preliminary load data sheet with loads for a dozen popular calibers. CLICK HERE to DOWNLOAD RELODER 17 DATA.
July 19th, 2008
CDNN Investments is a large retailer that often acquires overstock inventories of rifles, shotguns, and pistols, as well as shooting accessories. You can often purchase brand new rifles for 50% to 70% of the original retail price. And this includes major brands such as Winchester, Browning, Walther, and Anschutz. CDNN’s latest catalog was recently released and it includes great deals on Complete FN (Winchester M70-type) barreled actions ($399.00, p. 26), Winchester M70s (p. 44), and Steyr Hunting rifles (p. 43). CLICK HERE to download the latest catalog. (NOTE: this is a large, 38.4 megabyte .pdf Acrobat file.)
Among the items featured in the current catalog are Russian match rimfires (including an Olympic-grade 22LR pistol), a sweet little Winchester 22LR “Wildcat” for just $159.99, and a wide selection of Winchester lever rifles and falling blocks.
July 18th, 2008
German Salazar, a top small-bore and centerfire shooter, uses the 6XC cartridge for his long-range matches. German has tried a variety of different types of brass for this cartridge, including necked-up 22-250 brass and 6XC brass from Norma and David Tubb (Superior Shooting Systems). German’s measurements reveal significant differences in water capacity, as well as neck-wall thickness.
6XC Source Brass Dimensions
Case Capacity and Pressure Issues
German has noted significant variances in capacity among the different “flavors” of brass. Norma-headstamp 6XC brass has 49.3 grains of H20 capacity, while Norma 22-250 brass holds only 47.8 grains of H20. Third-generation Tubb-brand 6XC brass is somewhere in the middle, with 48.6 grains of capacity. NOTE: These differences in case capacity are large enough that you MUST adjust your load to the brass type. A safe load in Norma 6XC brass could be WAY over-pressure in necked-up Norma or Remington 22-250 brass.
We ran a 6XC QuickLOAD simulation with 115gr bullets and H4350 powder. QuickLOAD predicted that the observed difference in case capacity can result in pressure differentials as much as 4,500 psi! In other words, if you switch from Norma 6XC brass to a lesser-capacity brass type, your pressures could rise 4,500 psi (using H4350 and 115gr bullets).
Neck Thickness and Chambering Issues
German noted that the different types of available brass varied quite a bit in neck-wall thickness — from 0.0121″ (Norma 22-250) to 0.0140″ (Tubb 3rd Gen). Consequently the diameter of loaded rounds also varied. Depending on the brass you chose, your loaded rounds could be 0.267″ at the neck or 0.271″. That’s a huge difference and it’s something you need to take into account when you have your chamber cut for a barrel. For a cross-the-course rifle, you might want a chamber with .003″ total clearance over a loaded round. Obviously, to achieve that clearance, you’ll need to set chamber dimensions base on your preferred type of brass.
July 18th, 2008
Mark Deros of Alamo Four Star, LLC, has invented a new system that attaches Harris bipods to a Picatinny Rail mounted on the fore-arm of a rifle. The new locking system, called the DLOC-S, replaces the top plate of the bipod with a quick-release clamping system. The spring-loaded DLOC clamp allows the bipod to be attached to the rail easily with no screws or bolts to tighten. Just pop open the DLOC and slide it on the rail.
The makers of the DLOC system have created a video that shows the DLOC being installed on a Harris bipod with Poc-Loc. The whole operation takes less than 30 seconds and can be done without tools.
CLICK HERE to view DLOC 30-second Installation Video
The DLOC selling price has not been finalized, but Mark Deros expects it to be “under $100.00″. Product release is set for the second half of September, 2008. For more information, call (210) 432-7006.
July 17th, 2008
In order to allow larger photos, streaming videos, and other enhanced features, we have moved the Daily Bulletin to a new host. This lets us widen the layout. The page should also load more quickly. Don’t worry — all the archived entries since March ’07 are still there.
If you had book-marked our old bulletin page, www.6mmbr.com/bulletin.html, please change your bookmark. The new URL for the Daily Bulletin is:
http://accurateshooter.com/bulletin.html
VIDEO VAULT
We have also moved our dedicated VIDEO page to the new AccurateShooter.com server. The new link is:
http://accurateshooter.com/videovault.html
July 17th, 2008
This 7.5 minute professionally-produced video covers the Olympic Shooting disciplines. Created for Chinese TV, it offers good footage of air pistol and air rifle, 22 LR pistol and rifle competition, and the shotgun sports. You probably won’t understand the Chinese-language voice-over, but the video clips depict the action very well — even without English subtitles. If you’ve ever wanted to see Olympic-caliber shooters in action, this video is worth viewing start to finish. Gun content starts at the 35 second mark.
Click directly on video below to watch VIDEO from this page.
OR CLICK HERE to watch VIDEO on YouTube.
July 17th, 2008
In order to get exact dimensions for custom dies, and to monitor changes in the throat of your rifle, you may want to make a chamber cast. With such casts you can determine the exact dimensions of your chamber, throat, and bore (including land/groove diameters). Most chamber casts are made with Cerrosafe, a very unique compound that is ideal for the job. To cast a chamber, Cerrosafe is poured into the chamber and the first part of the throat. As it hardens it actually shrinks, allowing you to remove the cast from your barreled action. But, then what good is an undersized cast? Well, that is the magic of Cerrosafe. As it goes into its final hardening process, it “grows” back to the true bore/chamber dimensions. Brownell’s explains: “Cerrosafe shrinks during the first 30 minutes of cooling and then at the end of an hour, is EXACTLY chamber size. Cerrosafe melts between 158°-190° F.” To learn more about chamber casting with Cerrosafe, Click here for Gun collector Mark Trope’s illustrated guide to chamber casting, found on SurplusRifle.com.
Save 32% at MidwayUSA
MidwayUSA has 1/2-pound bars of Cerrosafe Casting Alloy (item 462291) on sale for just $13.57, through the end of July. That’s $6.42 off the normal $19.99 price — a 32% savings. As long as you keep the alloy free of contaminents the Cerrosafe can be re-used many times, though we advise you keep your chamber cast as a reference as long as you own the rifle.
July 17th, 2008
Folks email us regularly saying: “Hey, there was an interesting item in the Daily Bulletin, but I can’t find it now.” Take heart. Every Bulletin story is saved in our archive. You can always navigate to all previous posts using the “Older Posts” link at the bottom of this page.
The fastest and easiest method to find older posts is simply to search by keyword, or click one of the topic headings. If you want to find a video, for example, just click on “Videos”. If you’re looking for all stories about scopes, click “Optics”. To find a particular item, such as the story on Barnard actions, just type “Barnard” in the search field and click “Search”. Our search works very fast! Try it, you’ll like it.
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