Miller Time -- High Power Performer
Walnut 6.5x47 Beauty Shoots As Good as It Looks
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Californian Ken Miller is a High Power shooter who recently returned to the sport after a hiatus. Seeing that his older .308 Winchester gave up points in the wind to the hot 6mm and 6.5mm rigs, Ken decided to build a 6.5x47 dream rifle for long-range High Power matches (both iron sighted and scoped). Ken explains how this project came together and how he developed a superbly consistent load with Berger 130 VLDs and H4350. He also reveals some important tips on how to optimize your Lapua 6.5x47 brass to eliminate flyers and "keep 'em in the 10-Ring".
Back in the High Power Game with a New Caliber
by Ken Miller
In the past two years, I've resumed shooting in NRA High Power long range competitions. At first I wanted to see if I still enjoyed this, so I used a rifle that I already had. I took my heavy-barreled .308 Win, added a U.S. Optics ST-10 scope, and worked up some long-range loads with Sierra 175 MatchKings. Although I found that I was once again "hooked" on long range shooting, I also found that, even with good loads, the .308 was just not fully competitive in the strong and variable wind conditions we experience out West. (Although I admit folks like Gary Rasmussen and Michelle Gallagher can work wonders with their .308s.)
While at these matches, I noted that many of the winning shooters were using the 6.5-284, 6 mm Remington, and other calibers that had a noticeable edge in the wind. They shot bullets with a much higher BC than my .308 pills, and they drove their bullets at higher velocities. If I mis-judged the wind or mirage by just 2 mph, that moved my 175 SMK out two scoring rings. By contrast, if the same bad call was made by guys shooting high-BC 6mm or 6.5 mm cartridges going roughly 3000+ fps, their shots would only go out one ring. On the other hand, my .308 exhibits great barrel life, something that can't be said for some of the other calibers. One 6.5-284 shooter's barrel was "toast" under 1500 rounds. Since I'm not independently wealthy, and I don't own my own barrel and gunsmith shop, this didn't look all that attractive.
Comparative Ballistic Performance at 1000 Yards |
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Chart assumes standard atmospheric temperature and pressure. Windage is for a 2 MPH, 90° cross-wind. BCs are manufacturers' claimed values. Ballistics Data generated by JBM Ballistics Calculator. |
For my new gun, what I wanted was a very competitive caliber, with less recoil -- a caliber that burned less powder, and had longer barrel life than a 6.5-284. (I wanted 3000-4000 rounds at least). I also wanted a rifle that would fit me (with all of the adjustments possible) so that shooting would be more of a pleasure than a chore. After four months of research on ballistics, bullets, stock design, and optics and many talks with winning long-range shooters, I decided on the 6.5 x 47 Lapua caliber for my new 1000-yard match rifle. Now that the rifle is completed and successfully "baptized" in competition, I can say it was a very good choice of calibers.
Now that I've sorted out the brass issues, the load is rock-solid. In zero-wind conditions, the gun will put 10 rounds in 0.3" to 0.4". The Berger 130gr VLDs shoot great, and the 2900 fps H4350 load is eerily consistent:
I sent 10 shots over the chron and the ES was 11 fps, with a SD of 3. Yes, you read that right -- an ES of eleven (11) for ten shots. |
A Gun That Inspires Confidence
Something I have learned about shooting long range is that you must have confidence that the rifle and ammo combination you are using is absolutely going to hold sub- X-Ring. With this rifle, I know that if I hold and squeeze, and the crosshairs (or front aperture) are centered, the round is going to go into the X (barring some crazy wind change). Another thing I have found is that once I learned to adjust the rifle/sling combination properly, I no longer had that awful pain in the arm at the end of a 20-shot match like I did with the .308. With the new rifle showing both great accuracy and comfortable ergonomics, I hoped it would do well in competition. In fact, in the rifle's first 1000-yard match, I was able to post a 197-5x and 191-3x.
Choosing a Caliber
In developing my "dream" rifle, I first examined what calibers were out there and thoroughly researched their merits/deficiencies. Based on poor barrel life, I quickly took the 6.5-284 and similar barn-burners out of the running. That, initially, narrowed the field to the 260 Rem and the 6BR Improved (6 BRX or 6 Dasher). However, just as I was about to choose one of the 6BR Improved versions, I read an AccurateShooter.com article by Darrell Jones describing his new 6.5x47 Lapua. After reading that article, and then another feature story highlighting Don Nielson's success with the same cartridge, I knew that the 6.5x47 was the caliber I wanted.
Choice of Components: Barnard, Krieger, U.S. Optics
The "heart" of the new rifle would be a solid, single-shot action. After looking at a lot of them, I decided that the Barnard "P" action would be just the ticket as it was very stiff and came with a really good trigger (mine is set to about 2 pounds). So I called Mac at MT Guns and ordered the action, plus a mounting plate for my receiver sight. For a stock, I tried a number of designs and found that a clone of the Anschütz prone seemed to fit me best. I wanted a traditional wood stock, as I wasn't yet ready to go for one of those "new fangled" tube guns. My gunsmith, Doan Trevor, had an Anschütz-style design available, beautifully crafted from a solid piece of French Walnut. Not only was the stock a great fit, but it looked handsome as well.
Next I needed a barrel. I selected a stainless Krieger with a 1 in 8 twist so I could stabilize even the 140 grain-class bullets if needed. It is a medium Palma contour finished at 28 inches. Being cut-rifled, I thought that the Krieger might possibly provide longer usable barrel life. Doan Trevor then added a 3-way adjustable butt plate, an adjustable cheek-piece, and a rail for my hand-stop. He also custom-made a rail for my scope that didn't interfere with the receiver mounting plate.
The choice of a scope manufacturer, U.S. Optics, was easy, as I have been so pleased with the clarity and quality of my ST-10. I ended up choosing an ST-17, 17-power fixed scope, with mil-dot reticle, 35mm main tube, and the jumbo EREK elevation knob. The ST-17 rides in medium-height U.S. Optics rings. I prefer a fixed-power scope for a few reasons. First, with no power adjustment, there is less for me to screw-up. Second, the crosshairs/mil-dots always remain the same size relative to the target. Third, with variable power scopes, there is a lot more mechanical stuff to engineer, and therefore they are more expensive. A 10-power scope has an advantage that it actually gathers more light (same objective with less magnification means more light gets to your eye) so you can see better when conditions are bad, overcast, or in heavy mirage. The disadvantage of the 10X is that you cannot see your hold quite as well as with the additional 7X of magnification. If however, you have a really slow "wobble" and like to "hold off the spotter" from shot to shot (instead of moving your windage and elevation knobs like I do), U.S. Optics does make the ST-22, a 22-power, fixed scope.
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High-Tech Iron Sights
For my receiver iron sight, I selected the PNW Gold fitted with a Gehmann 565 iris combination filter eyepiece, which features glass color filters and twin polarizers. This is a very advanced eyepiece.
In the front is a Gehman 520A 18 mm adjustable (2.4-4.4 mm) front sight, fitted on a ladder (sight tower) made by Doan Trevor. To insure that I could see the number boards at 1000 yards, I augmented the front sight with an Eagle Eye DX-1820 0.5 diopter. |
Load Development and Accuracy Testing |
When I began this effort, I decided that I would try to duplicate much of what Darrell Jones had done, so when I ordered the chamber reamer from Dave Kiff at Pacific Tool and Gauge, I asked that he make me one to the exact same, "no-turn-neck", dimensions. This has worked out very well as it meant that my loading data would be similar to Darrell's. However, I later learned that a factory chamber for this cartridge appears to have a much longer throat, based on what I found when I examined a box of factory loads with my chamber test gauge. If I did it again, I might have the chamber throated 20-30 thousandths longer. That would provide a little more "boiler room" for the longer bullets.
One of the most enjoyable parts of this effort, besides shooting of course, was in developing competitive 1000-yard loads for this rifle. Not only was it intriguing to load a cartridge that wasn't yet in the loading manuals, but it gave me a chance to talk to others to get their loading advice for this cartridge. I planned to use the Berger 130gr, 6.5 mm VLD as "the" bullet as all my research indicated that this would be the ideal weight/BC for this round at long range.
Before loading my first round however, I contacted Darrell Jones and he suggested that I try the 120-123gr bullets with which he was having great success at 600 yards. He also indicated that he had not had much success with the 130-grainers (that later changed -- Darrell tells me he's recently running 130gr JLKs with much success). Don Neilson also suggested a lighter bullet. I did find some load data for the 130 Bergers on Robert Whitley's 6mmHot web site, so I called Berger Bullets. Berger's Michelle Gallagher thought I would get good results from the 130 VLDs in my Krieger barrel, and she recommended I "jam" them 10 to 15 thousandths. Turns out the Berger folks steered me right -- I've used the 130s exclusively in this gun so far, and they have performed very well.
Powder Choice -- Reloder 15 vs. H4350
I was looking for a powder that would fill the case, but not get me into trouble. The common suggestion by all was that I start with RL15 as it gave excellent velocity and great accuracy. However, I wanted a single-base powder as they have a rumored reputation for being easier on barrels. I ended up using Hodgdon H4350 (Darrell Jones' second best powder). H4350 was attractive because it was single-base, and it was slow enough so I would not be able to get enough powder in the case to blow things up (with the 130s).For primers I ended up going with Federal small rifle (205) because that is all I found in the local gun shops. I may try 205Ms when I get done with this lot of primers. For brass, there is only one choice -- Lapua.
[Editor's NOTE: With some heavier 6.5mm bullets you CAN exceed maximum pressures using H4350 in the 6.5x47 Lapua. So, always start low and work up.]
Lapua 6.5x47 Brass Weight Sort |
Weight Distribution of 200 sorted new, 6.5x47 cases |
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| The first step in my loading was to weight sort the brass by one-grain increments (i.e ± 0.5 gr). This was a bit disappointing as weight spread for the first 200 rounds covered 5 grains! Since this didn't leave me with 100 of any one increment (enough for one full High Power match of Any-Any and Any-Iron), I ordered 200 more from Bruno Shooters Supply in Phoenix and was able to get two, 100-round batches of matching brass. I took the heaviest brass I had (as this would be a worst case for pressure) and loaded them with incremental 0.5 grain loads starting at 39.0 going to 41.0. |
The light loads were really for breaking-in the barrel and then the rest were for pressure testing. The 40.5 gr loads looked good on the chronograph -- fairly low Extreme Spread (ES) and Standard Deviation (SD) -- and a 100-yard group went into about 0.3 inches, so I loaded up the first 20 of my weight-sorted (160.0-160.9 grains), match brass with 40.5 grains of H4350 to see how they would do at 600 yards.
The results were excellent (well sub X-Ring) and the chronograph numbers were very nice as well (ES 18, SD 6) at 2930 fps. I loaded and shot the rest of that lot of brass in a local mid-range 3x600 prone match to finish fire-forming. This also gave me a chance to begin experimenting with the settings for the length-of-pull, height of the cheek-piece, hand stop position, sling length, etc. After fire-forming, with the Berger 130s seated 0.010" into the lands, this same lot of brass, now turned in an amazing ES of 11 with SD of 3 at 2902 fps. That's for ten shots over the chronograph.
Mysterious Flyers Noticed -- Traced to Non-Uniform Neckwalls
With this rifle, there were some challenges early on -- I noticed that I was getting an occasional, unexplainable "flyer". This happened a couple times in matches. I would feel I had a sure 10, and it would pop out to an 8. That made me suspicious so I turned those cases upside-down in my ammo box for later inspection. When I carefully measured the "flyer" cases with a tubing micrometer, I found that the necks were a bit thicker than the rest and were NOT uniform. On some of the "flyer" cases the neckwalls had as much as .002" total variance (one side was thicker than the other, e.g. .015" vs. .013"). [Editor's note: Ken did the smart thing--segregate the brass that gave the flyers. We recommend this simple step for other calibers as well. You can mark the "flyer" brass with a Sharpie at the range, and measure them when you get home with a Neckwall Thickness Gauge.]
The obvious answer was to go back and turn, very lightly (to ~0.013), all of the case necks. Now I no longer have unexplainable "flyers", just the ones that the "loose nut behind the butt plate" generates. One other note on my reloading process is that I am using a Redding type-S full-length sizing die and the bushing (0.289") gives me just under 0.002" of neck tension. |
Competition Results -- A Masterful Performance in Arizona
In the precision shooting game, the "proof is on the target", or so they say. My 6.5x47 demonstrated its capabilities at the Arizona State Long Range State Championships in February, 2008. My scores were 190-5x, 196-8x (Any-Any), and 193-6x, 190-6x (Any-Iron). AZ Match Results. This may not sound impressive but these are solid Master level scores in this discipline. It was one of my goals at the outset to be able to shoot at that level. I'm sure that in the hands of a really top-notch shooter this cartridge could be right at the top of the leader board.
Final Thoughts and Lessons Learned
Now that I have had a chance to work out all of the issues with a new rifle/cartridge combination would I do it again? Absolutely! I'm very happy with all the hardware. In fact, I like the Barnard trigger so much I had Doan Trevor put one on my Remington Palma Rifle. When the barrel wears out on this rifle I'll re-barrel with the same barrel type, contour, twist and chamber -- though I might have the throat pushed out 0.020"-0.030", just to get a little more case capacity.
Engineering-wise, I learned that I needed to move the overall sight plane, with iron sights, up (which I could not have done except for the ladder type front sight mount which Doan and others recommended). When I moved the sight plane up, I was able to set the rifle up so that I was looking through the center part of my glasses. This insured that the front aperture didn't become blurred etc. when shooting. It also reduced strain on my neck.
This whole experience has enabled me to learn a great deal from a lot of fine rifle shooters who are also very experienced and skilled reloaders. I guess that's what makes High Power such an addictive hobby and sport. -- KEN MILLER |
NRA High Power Rifle Classifications |
Long Range | Mid Range |
High Master
Master
Expert
Sharpshooter
Marksman |
97.00% and above
94.00 to 96.99%
89.00 to 93.99%
84.00 to 88.99%
Below 84.00% |
High Master
Master
Expert
Sharpshooter
Marksman |
98.50% and above
97.00 to 98.49%
94.50 to 96.99%
92.00 to 94.49%
Below 92.00% |
NRA High Power Course of Fire
A typical Course of Fire for an NRA High Power Long Range match employs this format:
Match #1: Any-Rifle, Any-Sight, unlimited sighters, 20 shots for record, 1000 yards. Total time 30 minutes.
Match #2: Any-Rifle, Any-Sight, unlimited sighters, 20 shots for record, 1000 yards. Total time 30 minutes.
Match #3: Any-Rifle, Any-Sight Championship: An aggregate of matches #1 & #2.
Match #4: Any-Rifle, Iron Sights, unlimited sighters, 20 shots for record, 1000 yards. Total time 30 minutes.
Match #5: Any-Rifle, Iron Sights, unlimited sighters, 20 shots for record, 1000 yards. Total time 30 minutes.
Match #6: Any-Rifle, Iron Sight Championship: An aggregate of matches #4 & #5.
Match #7: Long Range Championship: An aggregate of matches #3 and #6.
The key, current NRA High Power Rifle Rules which apply to Any-Rifle, Any-Sight matches are listed below:
3.2 - Any rifle with no restrictions on sights or accessories, except that it must be safe to competitors and range personnel. Ammunition will be restricted to no larger than .35 caliber.
3.7(c) - Any sight without restriction as to material or construction.
3.16.1 - The use of compensators or muzzle brakes is prohibited.
The Any-Rifle, Iron sights matches require that the sights conform to the following rule:
3.7(a) - Any sighting system constructed of metal or equivalent which provides a method of aiming by aligning 2 separate but visible sights or reference points, mounted on the rifle, including tube sights and non-magnifying filters. A lens may be used in the front sight or the rear sight but not both at the same time. |
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Topics: Highpower, High power, NRA, prone, Anschütz, Doan Trevor, Prone stock, U.S. Optics, US Optics, ST-10, ST-17, ST-22, SN3, 35mm tube, Barrel, Krieger, 6.5mm, 6mm, 6-6.5x47 Lapua, 6.5x47 Lapua, Barnard, Model P, New Zealand, Berger Bullets, 130 VLD, Don Nielson, Darrell Jones, Scenar, 123 grain, Hodgdon, H4350, ADI, Extreme Powder, Vihtavuori, N550, Lapua Brass, no turn neck, neck-turning, Mac Tilton, MTGuns, Picatinny rail, Recoil Lug, .308 Winchester, 7.62x51, 308, Stainless, French Walnut, 6.5 mm, 6.5-08, Rem 260, 260 Rem, 6mmBR, 6BR Improved, 6.5-284, Switch-barrel, bipod, load development, Arizona Long Range.
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