My buddy and I bought a chrony together. We've chrony'ed different guns at the range. Biggest 's low shooters' IIR were 25-06 and 7 Rem mag. 270s were erratic. Most surprising to me is the 7-08, 26" barrel varmint special shot 140 Hornady light mags, at 2990 something. That's less than 10fps below advertised. Captdavid
Those Hornady 7-08 light magnum loads were fast, and their Superformance ammo shot over 3000 fps in a 7-08 I have that has a 24" barrel.