Need some load data for my 257 Roberts using Varget powder. I have been using IMR 4831 but want to try Varget. Any help appreciated!
Don
Ok Don,
for what bullets? Is this a modern bolt action that can take more or less standard +P loads (50000 cup) or is it an older gun the requires the use of the original SAAMI spec of 45000cup.
The actions that require the lower pressure loadings include but are not limited to Older and slide action rifles and any gun built on the Mauser 93 or 95 actions.
Speer has loads listed for the +P pressures and recommends that for the weaker actions you reduce their loads by at least two grains.
Speer recommends these +P loads as maximum for the 100 grain bullets that they make:
45 of WW760
49 of Re19
47 of H4350 (compressed load)
48 of IMR4831
50 of H4831 (compressed load)
45 of IMR4350
44 of H414
39 of IMR4064
42 of H380
These are maximum listed loads and in modern bolt action rifles you should start working your loads up at 10% below these.
Further reduce loads by at least two grains if your gun is an older model, a slide action, a Mauser 93 or a Mauser 95 action.
