In overview,the 338 Ultra is the LAST fhuqking chambering that needs "souped" up,as it comes outta da can in marvelous form. Now noone fhuqking hates the POS Wyatt's extended magboxes more than I and I'd much rather go DBM instead of that. For a straight up Killing Rifle I'd simply build a 24" 338Ultra that'd kiss a 250 Skinner in mag confines,leaving .050" or so to chase lands. I could happily suffer an extended COAL DBM on a Giggles Rifle.
Which DBM do you like for RUMs, 'Stick?
