Did you use a primer pocket uniformer on them before firing? If not, there could be just enough variation in depth to cause a difference in appearance.
Rick, I read about indexing cases ( the same position in the chamber where they are once fired )
I'm not going to sweat it though !
Dr. Vette, no I didn't uniform them !
I still have the charges still wrote on the cases when I did the work up ,so I'll go through them and compare the pockets to the best groups and bad groups and see if there's difference.
It really is no big deal , they all fired just fine.
I was pretty consistent with seating them.
I just found this and thought I would ask.
Last night, I pulled out all the first fired brass from that load work up.
I did two powder work ups.
W760 with cci250 and the imr 4350 with CCI 200.
I even looked at the factory Nosler 1st fired brass which they use WLRs .
The 4350 and CCI 200 with the best groups were light and heavy with deposits.
The cci250 and WLR loads were all heavy with deposits.
I think with in the 200s some were hotter than others but I guess it doesn't matter !
Nah, just ignore the gunk left over in the primer pocket. Doesn't matter.
Indexing cases...I'm sure it makes a difference, or German Salazar wouldn't do it, but...it doesn't make a difference! At least not for anything you or I would shoot. He's shooting at 1000 yds, and I think there's a bunch more to think about than we do.
Other items that absolutely do not matter:
1. How uniform your primer pockets are
2. Powder charge weight difference of 0.1 grain. It might not even matter at 0.3 grains for a 30-06. Think of the amount of powder more like the amount of cinnamon in a cinnamon roll. Sure, you need it, and a healthy dose...but if you're off by a tenth of a teaspoon it won't matter.
3. How clean your brass is. Dirty brass (tumbled), clean brass...they all shoot the same.
I'm sure a long list of other stuff too.
I think concentricity matters. I think a good powder/bullet combination matters. I think bedding and barrel matters. Beyond that don't make it too complicated! Just go shoot a barrel out and you'll figure it out along the way.
Have you ever seated a primer then run your finger over it to find it's protruding just a tad over the case head. Then seated it with a little more force only to find it's still proud of the case head?
That is the little radius in the bottom of the primer pocket that causes that. Look in the bottom of the pocket in the upper LH case and you can see it. As long as that radius is there not all the primers will seat uniformly and any that are proud will leave just enough space to cover the bottom with carbon. It is more noticable because these were new cases and you happened to look at them.
All a primer pocket uniformer does is remove that radius and cut all your pockets to the same depth, thereby making your cases more uniform. And uniformity is one of the tenants of accuracy.
I personally adher to this tenant and take any step I can to accomplish it. Even if some deem it unnecessary.
I bought a rcbs uniformer when I was buying all the tools to reload.
I did a lot of measuring of primer pocket depth and primer cup height going by the pocket and primer dimension charts and doing the math to see how it all works.
I did notice that the uniformer would not stand up level or square on the cutter end and this told me that when it cuts , it would leave the bottom of the pocket concave in shape.
I realized that everything was going to work out without modifying them and every time I would seat a primer I made sure they were below flush either using the probe of my calibers ,my fingernail. or standing the case up ,primer down to check for excessive wobble.
I will say that the rcbs uniformer will bottom out on a RP primer pocket but it won't on a nosler case .
The nosler pocket being shallower.
Being a rookie , I guess I'm just feeling the waters.
I have bought and use a Redding primer pocket uniformer.. In reading about the necessity to uniform pockets, it was stated in an article, and I do not remember where, that over time the pressure on the case head during firing will push brass back into the area of the primer pocket, necessitating its removal with a uniformer to allow proper seating of the new primer.
My cases are not fired that many times that uniforming removes much other than any carbon residue in most cases.
Just passing on what I remember, not promoting the extra step. Have a Great Day. Rol
Mine is the Lyman model, non adjustable, I've found a reason to complain. I read somewhere that the primer should be .005 below the surface. Mine are real close to that.