Thanks for posting this. I enjoyed reading it. I have rifles in all the gibbs cartridges from 6mm to 358 except the 8mm. I built all my gibbs hunting rifles on 26" barrels plus one extra in a custom lightweight with a 20 inch barrel in 30 gibbs just to see what it would do. The article seems to be right on with the results I get in mine. All calibers will virtually duplicate the standard magnum counterpart with less powder, recoil and noise. 6mm will eclipse a 240 wby ( more powder,recoil,noise), 25 will almost hit a 257 wby but not quite, 264 same as win mag, 7mm same as 7 rem mag, 30 between a 300 H&H and 300 winchester, 338 about the same as a 338 winchester and the 358 right at the 358 norma. There is certainly not enough difference in any of them to make a difference. It really just depends on the barrel and powder as to which one shoots the fastest. One of my 6mm gibbs is cut with a tight neck match reamer and is one of the most awesome varminter's I have ever seen.