I'm embarrassed I'm so confused about this; hopefully somebody can help me understand. I'm reloading Hornady Match 308 brass. 7th firing, tumbled clean with corn cob, annealed on AMP. Necks not turned. Shot out of a DT barrel, standard chamber. I'm using .332 bushing (I haven't reloaded .308 for a few years, I had a stockpile reloaded - I presume I have the .332 in the die for a reason, but I don't have notes. I generally have aimed for .001-.003 of "neck tension".) Cased lubed with Hornady one shot. Modest force required for sizing in the die. When the case comes out of the Redding Type S die with .332 bushing, the neck measures .328" OD with Starrett caliper; repeated measurements over and over; no force applied to calipers, measured delicately. When a bullet is seated, light force on the press arm is required to seat - seats "easily", like I think about .001-.002" tension would be, not .004" tension. With bullet seated, the neck OD measures .332". A sized case can be manually inserted into the bushing (removed from die) with mild-moderate force and the case can be rotated 360 degrees in the bushing manually - so it's tight in there and the "tightness" is uniform during a 360 degree rotation. If there were .004" clearance, I would think I could wiggle it in that bushing. A loaded round will not fit into the bushing at all - not even close.
So why the heck are my necks measuring .004 smaller (.328") than the bushing I'm using (.332")? For the life of me I can't figure this out, but I wonder if annealing isn't part of the equation. I'm tempted to buy a .333 & .334 bushing
Thoughts?
So why the heck are my necks measuring .004 smaller (.328") than the bushing I'm using (.332")? For the life of me I can't figure this out, but I wonder if annealing isn't part of the equation. I'm tempted to buy a .333 & .334 bushing
Thoughts?