no balls busted here. to bad i have the softest brass in the lot lol
yeah were the confusion is for me is ive heard it isnt safe to underload a cartridge so im mostly looking for a place to start. or if i should even waste my time with this bullet. as for your .0005 is that case expansion your talking about? nor sure if calipers are that sensitive pretty sure only.005.
boogz
Just average what start load data you have and work up, I have two AR15 rifles and a Savage .223 bolt action with a 1 in 9 twist and the throat is longer than my AR15 rifles. Meaning the Savage can be loaded higher/hotter than my AR15 rifles can.
Again by working up you will learn how to read your primers.
Pressure increases from left to right, the last primer on the right is screaming time to stop and back off the load.
Below a Quickload chart for my AR15 load, max pressure for the .223/5.56 is 55,000 psi and my pressures for my practice ammunition is 50,000 psi and very easy on any make/type of .223/5.56 case.
Your question of case head expansion, .0005 is where you would first see case head expansion "IF" you had a vernier caliper capable of reading that low. Readings of over .001 is where to check and see if this is causing problems like loose primer pockets, and this expansion varies . And as long as you do not load at maximum pressures you have nothing to worry about.
Measuring the Case
by: Germán A. Salazar
http://riflemansjournal.########.com/2010/03/reloading-measuring-case.html
Resizing - Case Dimension Changes
by: Germán A. Salazar
http://riflemansjournal.########.com/2010/06/basics-resizing-case-dimension-changes.html
SIMPLE TRICK FOR MONITORING PRESSURE OF YOUR RIFLE RELOADS
(NOTE as you see at this link below expansion varies with the type case and how hard the brass is and they are ballpark)
http://www.hodgdonreloading.com/reloading-education/tips-and-tricks/simple-trick-monitoring-pressure-your-rifle-reloads
At the Accurate Shooter website many competitive long range shooters will increase the load until the brass flows into the ejector. This lets them know the elastic limits of the brass and they back off one or two grains of powder and then look for the best accuracy near max.