[Sevens]

There are some certain cases (snicker) where a +P headstamp has an actual difference in construction... but for the most part (and for the purpose of this thread), the only difference is in the head stamp, just as Miata Mike said.

I am one who will always separate head stamps in all my brass, and I do it every single time and I load a heckuva lot more handgun than rifle.

There is the possible accuracy/consistency angle to it... I'm not sure there's going to be a discernible difference with the guns and ranges we shoot it.

There is the OCD/pride angle to it, where all your ammo looks proper. (for me, that's important)

But the biggest reason that I do it has not yet been mentioned by anyone. I do it for ultimate consistency at the bench and through my loading dies.

All you have to do is take 3 pieces of R-P brass and run them through a flare die and then run 3 pieces of CBC/Magtech through the same sizing die with the same settings and you can easily feel the large difference in resistance in the press lever.

The cases do NOT have a consistent thickness nor malleability between mixed head stamps. When you simply go with mixed, you open yourself up to much more possible case mouth tension issues and your risk of unintended bullet setback raises dramatically. (in my opinion, of course)

Don't get me wrong... I use most all head stamps... it's quite simply that if you open one of my boxes of ammo, you are going to see 50 rounds and only one headstamp. You open the next box and you may find an entirely different headstamp, but there will be only one kind in that box -- and 50 of them. I will sometimes make slight adjustments to either my flare die or my crimp die (or both!) when moving to different headstamps.

(typically, I'll do a run of about 200-500 loaded rounds, usually all with the same head stamp, but that has more to do with my brass supply in that caliber than anything else)

We can all agree that in some chamberings... when using certain brass... and a particular bullet, you will get a particular "feel" in that press lever when seating and crimping, yes? There's a "feel" that speaks to you and says, "dead solid perfect" and there's the lever feel that also says, "holy hell, is there even a bullet in there? Why is there no resistance? Will I have ANY case mouth tension or is this bullet going to fall inside the case?"

Do it for enough years and you'll be able to predict your lever "feel" before you even powder charge a case simply by the bullets you have, the brass headstamp you are using and the feel from the lever on the flaring stage.