Rock River Arms Lar 15 Review. They sent me frontier 5.56, 62 gr. 7 rock river arms ar ar15 carbine a4 5.56mm 16in.
My particular rifle (as pictured above) has a 16″ barrel with a 1:9 twist. I was told this is the ammo hornady typically supplies the untied states military. They later formed their own company, tolerance plus (later rock river arms), producing 1911 pistols.
It's accurate and has several bells and whistles that you will come to appreciate.
I'll demonstrate the accuracy of this ar15 carbine at ranges from 100 yards. I think rock river's weapons are much more than that. Fit finish and function is above average, and. April 22, 2019 by steve gash.