Excellent thanks who much for all the help and great info guys. Thats the great thing about this place. Lots of great and helpful people.
One last question. My first batch I plan on loading with less powder than the lowest velocity the hornady book calls for. How much less powder should I use?
do
NOT load less then book ( .4gr may be) , you can get overpressure this way as well , you should / need to read as much as you can about reloading before reloading if you’re planning on playing with accuracy nodes, fast or slow loads.
My load work up : there are other methods
what I do when working up a load is work up in 1 gr increments so for 300wm using re-22 (powder) and 180 gr bullet my powder range is from 73gr to 77gr (from the BOOK) I'll make up 3 or so round of each in 1gr increment , so that 3 rounds @ 73gr, 3 rounds @ 74gr, 3 rds @ 75 gr....etc..
I'll shoot them @ 100m to see which group the best in my case it was the 74gr. ( this gets me my rough accuracy node)
then I make up some more rounds starting from 73.6 gr ( .4gr below my rough node) up to 75.4gr going in .2gr increments I'll make 5 of each increment
I'll shoot 3 rd groups @ 100m to see which one groups the best.
then I do two ladder type tests @ 300m
I'll shoot @ a 4' x4' pc of plywood covered with paper so I can see hits, i then shoot 1 of each increment 73.6, 73.8, 74, 74.2, ....so on
at the same aiming point.
the key to this test is to know where each shot hit and which increment it was:
for example:
1)my first round was 73.6gr hit low from my aiming point
2) 2nd slightly higher
3) 3rd higher yet
4) 4th hit the aim point
5) 5th was higher
6) same height as #5
7) same height as #5
8) same height as #5
9) 9th was higher and so on
shots # 5 through 8 are in the accuracy node, I compare this to the 100m test to see if the best group was in the same range if so then this confirms to me that I'm in deed in the node (this node was from 74.4 to 75gr)
I then work a load using a powder value from the middle of the node for me this was 74.7gr , you can then mess around with .1 gr increments, bullet seating depths etc... but I didn’t go that far.
Point to note is to document what you are doing, if you neck size only, if you full body size, how many reloads are on the brass, specs you are loading to etc… reloading for accuracy is about removing variables and being consistent much like long range shooting.
Another good site to read on in benchrest forum
http://www.6mmbr.com/index.html
Hope this helps and dose not confuse.