firstcouse I can't because I have never used the 175 in the LRM...cause I never had one.
But I did have a 7mm Dakota which is very much the same thing as the LRM but with a slightly different head size. I basically used the Barnes Manual data in working up loads for the Dakota and found the velocities very much spot on.
When I was working with the Dakota I noticed that RL22 did very well with lighter bullets but when I got to bullets of 150-160 gr, the powders with burning rates like RL22,H4831 etc did not do as well in accuracy and velocity...I went to RL25 and it worked very well with 150-160 gr. bullets.
I never got to the 175's in the Dakota.
However I was on the website for the Gunwerks 7mm LRM and noticed their top charges with the 175 and H1000 were within a grain or so of what I use in the 7mm Mashburn Super...and velocities were similar as well. Bottom line is I think these cases are very much the same and if you find RL25-175 data for the 7mm Dakota I think you could back off and work up with the LRM and end up at about the same place. That's how I would do it.
I also think you will find that Retumbo and/or RL25 will be excellent and capable of a bit more velocity than H1000 but not by much.
