The problem I had calling them once before was they didn't want to acknowledge that the round can be safely loaded to modern pressures.
You're going to find that with older classic rounds, like 6.5x55, 7x57, etc.
Some providers will give loads for modern actions, some stick to vintage gun limits.
I like to research on line for that type data. Load Data is a good source, but you have to subscribe. To me, it's a good deal, as they have most proprietary loading manual data and you won't have to buy a stack of those to have the info.
DF
