I would load 1 shot each of the lower charges just to check the for pressure signs.
My Berger books states that as you increase seating depth you are in effect increasing case capacity and can increase velocity.
I have used a cheap MTM scale for a year and it works just fine.
If you need more than +- .1 or .2 grain accuracy you may not want to use one.
My question is who needs that much accuracy?
Can you see the difference in your groups.
I think not.............
5.56mm Nato 22.0-24.9 grains
.223 Service Rifle 19.4-23.3
The 2013 Hodgden Annual manual has a couple of good articles for this caliber.
Picked mine up at Wally world the other day. 9$
I would not interchange any powders or bullets.
The Hodgdon H4831 is an extreme powder that has an additive that makes the powder much less sensitive to temperature changes.
I use the extreme powders with Hornady bullets because they shoot just as well for about half the cost.
You can...
I bought the Lee book and a Lee press kit. I added some dies and a cheap MTM scale.
No problems in 2 years and all my rifles shoot 1/2 MOA with custom loads.
I only neck size fire formed loads.
Save some cash and try it out.
If you have doubts just buy the Lee book and you will learn...
I use the Hornady SST's. Just as much bullet for about half the cost.
130 gr SST
53.2 gr IMR 4831 COL 3.19 Win WLR Primer
or
57.7 gr H4831SC COL 3.235 Win WLR Primer
or
140 gr SST
59.5 gr H1000 COL 3.34 WLR Primer (my favorite)
All win brass and Lee equipment with a...
41.6 gr H4350
Win Brass
WLR primer
2.64 COL
Hornady 87 gr V-Max
5 shot groups inside a dime.
Note: 43.4 gr is Maximum load, work up slowly if you need the 50 to 75 fps.
I had to wait 30 day's for a "Proceed". Went back filled out the form again and waited two more day's for the "Proceed".
So much for "instant" checks, NICS is a joke.
I never had a problem until the "Supreme Muslim Leader" was elected............?