HH-50
Lots of powder tend to change. and if your one that uses a powder drop or scoop of some sort the weight will change per volume of the scoop or drop say like the Lyman 55.
I don't have a set of weight or volume that I start loading a bunch of match ammo with and go and shoot a match unless it's the same lot of powder, bullet, primers and wads I used before for that rifle.
I just opened a new case of Swiss getting ready for a match at Lodi Wis and I went through some ladder test loads and the weight of the best I used on the last lot has changed but the compression stem in the compression die I have set for the seating depth is still the same. I don't change the seating depth that holds my PP bullets.
The ladder loads start with zero compression and that sets the starting volume in the case and also take the wad stack thickness in mind for the zero compression then I weigh that volume of powder and that will be the starting weight for my ladder loads that increase by one grain per 2 shots to 5 shots of the same powder charge. I like starting with 2 shots and pick the best group and follow up with 5 shots of the best three to verify the first best two shots.
Below is the ladder load target I shot yesterday with this new lot of Swiss.
I shot this at 100 meters because the 200 yard line was shut down for work but that is just as well because I can see those targets better and get a good sight picture to eliminate sighting errors. Those orange posters are 1.5" and that black diamond in the center is 1/4" and that is large enough that I can see it through my 8X scope to get a good sight picture, and at 100 mtrs the wind is less of an factor.
I don't have a place I can work on loads farther than 200 yards so I use that range for a 5 or 10 shots to verify those two shot groups and go shoot the match.
Yes this is a lot of shots fired but this also gives me trigger time so it serves a lot of purposes. Trigger time is just as important as a good load.