A full-time lawyer, Robert Whitley is also an avid prone, Highpower, and cross-course shooter. Over the past two years, Robert has pioneered a cartridge for these disciplines (as well as long-range varminting) based on the 6.5mm Grendel necked down to 6mm. Robert calls the cartridge the “6mmAR”.

The 6mmAR cartridge has performed very well in AR-based comp guns, both with shorter bullets loaded to mag length, and 105-107gr bullets single-loaded. Robert has complete info about the 6mmAR on his website, 6mmAR.com, including recommended loads and field test results. Robert has also developed a higher capacity version, with the shoulder blown forward and a shorter neck. He calls this the 6mmAR Turbo. This round can drive 105-108gr bullets in the 2850-2900 range, and it has proven very accurate. It is one of the best options for AR-platform space-gun shooters.
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Though making 6mmAR brass from 6.5 Grendel brass is quite straight-forward and simple, Robert receives many questions about forming the brass, so he recently prepared a video. The two-minute video shows how quick and easy the brass-forming process can be:
Robert also builds and sells products for across-the-course shooters, including complete AR uppers, chambered in a variety of calibers, including 6mmAR. Jerry Tierney, 2005 NBRSA 1000-yard champion, has a 6mmAR upper built by Robert and Jerry says the upper “Absolutely shoots great. I love it.” In the past few months, Jerry has broken many NRA senior records with his new 6mmAR-chambered rifle.
CLICK HERE for Feature Article on 6mmAR and Robert Whitley (many photos)



The 6.5 Grendel cartridge has recently received some significant factory support from Hornady. Brass, dies, and loaded ammunition has been announced for 2010 from Hornady.
http://www.hornady.com/store/6.5-Grendel-123-gr-A-MAX/
Comment by Doug — November 13, 2009 @ 12 pm
You left out the latest development in the product line, the Turbo 40 degree improved:
http://www.6mmar.com/6mmAR_Turbo_40_Improved.html
Comment by Tony Chow — November 13, 2009 @ 1 pm