Arisaka
I'll amend this to say that I found the Arisaka to be exactly what i wanted for a 13" ALG rail, the ergo rail that has a small piece of picatinny forward. I have an Inforce light mounted and it was just a little something, I could live without it but it's nice. I position it between my index and middle finger. I've setup two this way and they really work well for me. However on a BCM 15" rail it was a little different. Running a light with a tape which on top of the rail. Because of the hexagonal or octagonal shape it didn't reel the same. The ALG had something built in to guide my hand or i guess keep it from going forward. I tried the BCM KAC grip. I really really like the design, it weighs next to nothing and you can pick one up used for $15. I tried it and turned it around like another poster suggested, I think it would work really well for most people but I just couldn't get it to feel right. I ended up switching it out to one of their stubby hand grips and use a modified clamp grip with it acting as kind or a back up support for my hand. I like this too for that setup, 1-4 with a B5 stock for a better cheek weld where the other is for super quick target acquisition, lower 1/3 dot with a BCM gunfighter stock. For what it's worth....