So I am getting close to start my reloading journey and I want to do a proper load development for my rifle. The components I will be using are Alpha Munitions brass, 140-142 grn projectile, and H4350. My main concern of my load development is I would like to see what my max CBTO (cartridge base to ogive) length is going to be then run .020 off the lands starting out. My question is how do you establish a load when you are using all new components (brass) and develop a consistent load from the new brass compared to the fireformed.
I wont go into detail with my entire process I intend to use but I will lay out a general overview.
1. New brass, inspect for dings, burs in the flash holes, if all are good I wont resize or do any brass prep.
2. Find COAL using Hornady COAL gauge, measure headspace of Hornady case and Alpha brass and subtract difference then subtract.020 for .020 off the lands.
3. Charge and seat bullet with the measurement I got from the Hornady tool.
4. Perform optimal charge weight test and determine a load the gun likes
This is where I am confused. I now have once fired brass form my rifle that has grown. I know I want to set my shoulder back .002 and trim my case neck. However since I used new brass, my COAL has now changed since it has been fired in my rifle and is now larger since I only set it back .002. How do I seat my bullet in the fire formed case and do I use the same charge weight that I discovered with the new brass or will I have to do a new load work up? With the case being larger I will technically be seating my bullet deaper in the case if I used my new brass COAL measurement. Also do I trim my neck to the same length it was as new brass or do I need to calculate that in as a new measurement as well.
I know this may be a confusing post but what it all boils down to is how can I find a load that works in my rifle so I can use new brass or fire formed brass without wasting a lot of components just so I can start with fireformed brass.
I wont go into detail with my entire process I intend to use but I will lay out a general overview.
1. New brass, inspect for dings, burs in the flash holes, if all are good I wont resize or do any brass prep.
2. Find COAL using Hornady COAL gauge, measure headspace of Hornady case and Alpha brass and subtract difference then subtract.020 for .020 off the lands.
3. Charge and seat bullet with the measurement I got from the Hornady tool.
4. Perform optimal charge weight test and determine a load the gun likes
This is where I am confused. I now have once fired brass form my rifle that has grown. I know I want to set my shoulder back .002 and trim my case neck. However since I used new brass, my COAL has now changed since it has been fired in my rifle and is now larger since I only set it back .002. How do I seat my bullet in the fire formed case and do I use the same charge weight that I discovered with the new brass or will I have to do a new load work up? With the case being larger I will technically be seating my bullet deaper in the case if I used my new brass COAL measurement. Also do I trim my neck to the same length it was as new brass or do I need to calculate that in as a new measurement as well.
I know this may be a confusing post but what it all boils down to is how can I find a load that works in my rifle so I can use new brass or fire formed brass without wasting a lot of components just so I can start with fireformed brass.
