May 11th, 2008

6-6.5×47 Varminter with Trick Mount for Rangefinder and Spotting Scope

Forum member Scott S. (Sunbuilder) has built a sweet long-range varminter based on the 6.5×47 Lapua cartridge necked down to 6mm and then improved to 40 degrees, with slightly less body taper. Scott tells us that “improving the case adds about 2.0 grains to the case capacity”. This allows Scott to run the 103-108gr bullets at well over 3100 fps, with no pressure issues. Scott calls his Improved case a “Long Dasher”, a name suggested by Dave Kiff of Pacific Tool & Gauge.

A Better Mount for the Spotter and Rangefinder
Scott designed and fabricated a very slick set-up to hold his Zeiss spotting scope and Leica CRF RangeFinder. He’s built a combo bracket that holds both units rock steady, with a parallel line of sight (same axis and elevation). Smart. Very smart. Scott explains: “I built a mount to connect my rangefinder to my spotting scope. The mount can be adjusted, so the spotting scope and rangefinder are both centered on the same object. The only way I have found to get repeatable long-range readings is to make them from a stable base.” Scott, we think you’ve got a winner here with your innovative and clever design.

sunbuilder spotter and rangefinder mount

6-6.5×47 Improved Works Well with Many Powders
Scott’s 6-6.5×47 Lapua Improved varmint rifle features a Stiller Diamondback action, Lilja 30″ 8-twist barrel, Richard Franklin stock, and a NightForce 8-32×56 NXS. Scott has had excellent success–his two longest groundhog hits were at 778 and 810 yards. Scott has tested many powders with his 6-6.5×47 wildcat: “I tried several powders (H4350, N160, N560, H4831sc), and primers (CCI 450, BR4, Rem 7 1/2, Fed 205Ms). I got better velocity with H4350, but my barrel likes the N160. I did find a [high-speed] node with H4350. The increased velocity potential of this cartridge is partially due to the slightly increased case capacity. The load I am shooting now is 40.5gr N160, Berger 105gr Match BT, .010″ jam, CCI BR4, .002″ neck tension at 3115 fps. This has an ES under 15 fps, and it will group under 2″ at 500 yards if conditions hold. This ‘Long Dasher’ (6-6.5×47) seems to have a lot of potential (and that’s an understatement).”

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May 11th, 2008

6BRs Dominate Mifflin Groundhog Shoot

Pennsylvania’s Mifflin Country Sportsmen’s Assoc. held one of its triple-yardage Groundhog Shoots on May 10, and the results just came in. This is a very popular match with targets at 200, 300, and 500 yards. It’s a score match, so small groups are nice, but they better be centered. We were interested in the match results because it shows the rifles that folks are using, and what’s winning, in both factory class and “Custom Limited” classes. (At Mifflin, Custom Limiteds are typical 600-yard benchrest Light Guns–full customs weighing 16.5 lbs or less.)

In Custom Limited Class, 8 of the top 10 places were taken by 6BRs, with one 22 BR, and one 6 PPC. That’s a pretty emphatic demonstration of both the popularity and the accuracy of the 6BR cartridge. Rod Morton and Steven Kotecki tied for first with 143 points apiece. Rod was named the winner, based on “X-Count”, as Rod had 7 “Xs” compared to 6 “Xs” for Steven. Now that’s a close match. Joe Pellegrene was just one point shy, to finish third with 142 points.

In the factory class, Jesse Hall, a Junior, had highest score, 125-1x, shooting a .223 Rem. Next highest factory shooter was Bill Slattery with 119-3X, also shooting a .223. The .223 Rem was the most popular chambering in factory class.

Can the .223s shoot with the 6BR? Looking at the scores, the .223s were pretty competitive at 200 yards, and even 300, but at 500 yards, most of the better .223 shooters were scoring high 20s, while the top 6BR shooters in Custom Limited class were in the mid-40s. (Junior Nick Sinkus did, however nail a 40 at 500 yards with his factory .223 Rem — great shooting by the youngster.)

CLICK HERE for Mifflin 2008 Schedule of Events.

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