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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