A google search turns up this:
http://www.gunhuntermag.com/Features/030818Tamale.htmlThis smacks of the typical hyperbole which accompanies some wildcats, and the author here has fallen for much of the hype. The originator of the 7mm STW developed the .257 STW himself in 1997, and using his custom rifles reached a maximum of 3807 fps with 100-grain bullets in 26" barrels. This is well documented in the June 1998 issue of ST.
I don't doubt that Ferguson got 4060 fps in
his rifle, but at what pressures? Safe, presssure-tested loads in the 7mm STW (Nosler data) only achieve 3610 fpe with a bullet of the same sectional density; the Ferguson load developes more energy than that! Experienced reloaders know that the same case cannot achieve the same energy with different bullet diameters - the smaller bullet has less area for the gas to push on so it cannot receive the same amount of energy. To achieve that 4060 fps load, the pressures are obviouisly well above the SAAMI specs for the STW cases. Simpson's own top load achieves 3220 fpe, which is much more reasonable and in line with what can be expected when compared to the 7mm STW and it's larger diameter bullet.
But even with a max velocity of 3800 fps, this cartridge is well above .257 Weatherby levels and would make a fine long range medium game cartridge. It doesn't need hyperbole and excessive pressures to get there either.
