Re: resetable windage/elevation target knobs with positive stop?
I finally found the Brownell's catalog update insert I've been rooting around for. I thought it was the Nightforce Zero stop, but it's the D&L Sports "Speed Turret" knobs for retro-fit.
NXS Long Range and Leupold Target knobs give four complete revs, and the NXS Medium Range gives two full revs.
100-001-767 NXS LR Speed Turret
100-001-768 NXS MR Speed Turret
100-001-769 Leupold Target Speed Turret.
I don't know if the Leupold Turret is any better than the Kinton Industries turret.