I can't see how a top rib tapering in width to the muzzle helps in any way other than making the appearance similar to that produced by optical recession on a rib 30-32" long. G. T. Garwood thought ribs of almost any sort created shadow lines (lines of sight or alignment) with the adjacent barrels which registered in what might be termed the subliminal optical consciousness. 26" barrels of my experience are too easily pushed and too easily stopped; 25" must be the same.

jack