Starting with new brass

[cdherman]

When working with quality brass (lapua, norma, RWS) the flash holes will be fine without reaming or chamfering. I would never FL resize new brass with a standard FL die. Those dies push the whole body down, as well as the neck and then pull the expander back through the neck. You are working the brass -- resulting in hardening. More hardening equals variation in neckg tension, which results in inaccuracy. Nevermind split necks eventually.

For virgin brass, my choice after a lot of reading and use, is the Sinclair expander mandrel. With quality brass, new stuff, I expand to using graphite (no need to clean afterwards), then champfer. That cleans out the dented necks and uniforms the inside neck dimensions so that bullet tension is uniform.

Later, annealing is needed. Different thread....

Standard FL dies tend to size the neck way down and then open back up with the expander ball. This is fine for average work, but it works the brass, and early splits will occur, as well as variable neck tension.

 

[lancetkenyon]

When working with quality brass (lapua, norma, RWS) the flash holes will be fine without reaming or chamfering. I would never FL resize new brass with a standard FL die. Those dies push the whole body down, as well as the neck and then pull the expander back through the neck. You are working the brass -- resulting in hardening. More hardening equals variation in neckg tension, which results in inaccuracy. Nevermind split necks eventually.

For virgin brass, my choice after a lot of reading and use, is the Sinclair expander mandrel. With quality brass, new stuff, I expand to using graphite (no need to clean afterwards), then champfer. That cleans out the dented necks and uniforms the inside neck dimensions so that bullet tension is uniform.

Later, annealing is needed. Different thread....

Standard FL dies tend to size the neck way down and then open back up with the expander ball. This is fine for average work, but it works the brass, and early splits will occur, as well as variable neck tension.

An FL die will not bump the shoulders back on virgin brass if it is set up correctly. Like if you have it set up to only bump fired brass .002". I have found MOST virgin brass to be shorter than chamber dimensions by more than .002".
If virgin brass is annealed (like Lapua is), a single pass through a die will not work harden it enough to cause any issue. If virgin brass is NOT annealed from the factory, I always run it through a die, tumble, then anneal it before loading anyway.

I anneal after every firing and FL resizing, and have yet to have any split necks on brass that has been fired 10+ firings. I usually lose primer pockets before that. The only other issue I have ever had was on a single Rem R-P case in 7RM that had a slight case rupture just above the belt after the 8th firing. Case shoulder always bumped back .002", same as any other case I reload, belted or not.

 

[Rick Richard]

Yep, most new brass is below chamber dimensions and needs to be "blown out" to chamber dimensions before resizing.

 

[Mikecr]

To an earlier post about confirming .2s in the first 10shots, this is not load development.
This is merely validating all that is known with a system. Change ANYTHING from known; bullets, powder, primers, seating, etc., and now you'll likely need to develop with that change before expecting .2s, even with all else known.
Just getting this back to reality..

Every gun I've bought/had built is different. It's always starting from unknowns.
The only time I can expect validation instead of development, is with barrel changes that include the same exact chamber(same reamer/barrel finisher). Even then, this validation is with fire formed cases. That's what I shoot. If you're a reloader, it's what you'll shoot.

 

[gohring3006]

I need stability to get some sleep. New brass is not stabile.
I usually feel differences in bullet seating, it's not even the same size as it will be, that's why I neck size for two firings, then set up my die. I don't even get serious until those steps are done, I also wait till a new barrel has 200ish rounds on it, and I'm confident it's stable. This 200 round "break in" also gives me a chance to work out any bugs in the system, like scope base loose, bad scope, bad bedding, etc. once I'm there, I'll get the Chrony out and get serious with loads. I also take into consideration, bore cleaning and the copper equilibrium, or in my case, Hex boron nitride equilibrium.