Quick load help

Hi I have been running GRT (Gordons reloading tool) but have come across an issue with one powder.

ADI BM8208...... actually they dont list it at all but have its American brand IMR 8208 XBR.
The issue is they list it as slower than ADI 2206H, but the ADI manual lists it as faster.

I would like to try this in a .303Brit as I read on here that NZ NRA used 2206 ( no H ) back in the day so BM8208 will run pretty close to it, all be it a little faster
Starting load of about 41 Grains is what I think but would like to confirm where it will be with QL

Case capacity is 54.8 grains H2O OAL is 78.35 running a Sierra 174 HPBT

I would like to achieve 2600 fps but remain under the pressure max, otherwise I will go with 2206H

Barrel 26 inches

Any input apreciated

This is an issue with several powders, and I wonder if its to do with the "crudeness" of burning rate as a measure. GRT also says a couple of the supposedly equivalent ADI and Hodgodon powders have slightly different properties. The only thing I can think of is the batch to batch thing.

The last thing is that it always pays to validate GRT and Q/L against other info sources . . . something I'm sometimes too lazy to do, it'll bite me on the ass one day

Just checked and I did have Q/L on this PC - but it doesn't show either 8208

@Tentman yes I think its been an issue before ( 8208 on QL ) My estimate of 2600 fps might be a bit fast too for the powder/ bullet:)