I use the COW (cream of wheat) method on 22-250AI and 6mm Rem AI. The rule I was told is to measure the case volume in grains of water and then use 10% of that volume in Unique. Adjust the powder up until you get good sharp shoulders. I am running closer to 15% in mine. I think 10.5 gr in my 6AI. Powder, then fill to the neck with COW, then put a wax plug in the end. I used to use toilet paper, but if a piece gets under the neck and is fired several times it is PIA to remove. It is messy on the barrel. Clean after 20-25 rounds, even if your going to current shooting. It will get the barrel hot. Don't fire off 25 rounds as fast as you can pull the trigger.

BYI - I would just as soon use a stiff load with a bullet seated in the lands in my 6mm AI, but the gunsmith ran the reamer in a little deep and I have to form a false shoulder on the neck to get reliable firing, so the COW method is much easier with my 6AI. On my 22-250, I usually just buy cheap white box Winny ammo and fire it to get my brass.

The good think about the Ackley chambers is the brass will last forever. A little should bump and your ready. I have neck sized only the 22-250 AI for 3-4 firings without having to do a shoulder bump.

Luck, Tim