Case Prep for the AR10
This is directed specifically at the AR10.
We use one type of case only. The Lake City LR, and our lot of 1,000 is a 2004 Mfg stamp. These are once fired and collected by Bartlett. If the LR is not headstamped then you probably have machinegun fired Lake City.
The first step is lubing, and we use Castor Oil. Yeah, I know. There are many hundreds of threads and thousands of posts all over the net about "the" best lube. Want to waste your money? Go for it. None of them beat Castor Oil. Its cheap and takes no more than 3 drops to do 100 cases. We line a shallow baking pan with foil, a few drops of Castor Oil, roll them around a couple of times and that's it. This is just for a demo. We usually do 100 at a time.
We use a side bench mounted neck lube brush that has a miniscule amount of Castor Oil on the bristles applied with fingers.
Resize and de-cap the primer, then...... remove the expander rod. Resize with a bushing die of the right diameter. We have a separate press for each process, but if you don't you'll need to go through the sizing process twice, once with the Expander/De-capper and once with the bushing die. We use Redding Micro's for both processes.
A quick wipe.....
And on to the Wilson Trimmer. Use what works for you, but whatever it is, be certain that there is not one iota of variance case to case.
Ream and Champfer gently. There's no need to be aggressive with the brass.
Insert primers. For this process we use the RCBS built in primer seater. A new Forster will be here this week and that will be dedicated to two processes, one of which is primer seating.
I've purposely ignored primer pocket truing and I'll explain why later.
For projectile seating we use the Redding Micro and that, for us, is critical.
We have electronics, but for precision reloading we use a very long I beam scale.
Next will come seat depths and primer pocket truing.