Reaching maximum load safely

[ar15barrels]

The attached picture is what I am seeing on some of my uncleaned brass now... Doesn't look like it's ready to break but the line shows pretty clear... maybe one more reload on these cases?

That's likely just the normal case expansion in a sloppy loose chamber.
How many reloadings do those cases have?

[dscoduc]

That's likely just the normal case expansion in a sloppy loose chamber.
How many reloadings do those cases have?

I received a bag of about 130 used cases when I purchased the (slightly used) barrel and bolt... So for these cases I have reloaded three times - all with loads closer to the minimum than the maximum.

I understand using unknown sourced brass is a crappy way to go so going forward I buy factory rounds (20 per box), put the once fired brass back into the box, and then prep/reload per box so I can keep track of the reload count.

Today while in the shop the guy told me he runs the cases until the wheels fall off... can't imagine I want to do that though...

[ar15barrels]

I received a bag of about 130 used cases when I purchased the (slightly used) barrel and bolt... So for these cases I have reloaded three times

In order to increase the life of the cases, you only need to be sizing the shoulder about 0.002" back when you resize.
You need to have an accurate method to measure shoulder lengths to verify that your sizing die is set correctly.
Minimizing the sizing will eliminate worries of case head separation.

[PrimaryArms]

Reaching maximum load safely

^^^ This what Ar15barrels said

Like others pointed out C is compressed and if your hitting the sweet no need to go further there is no advantage to an overpressure load. Flat primers and stretched out primer pockets are the first things I noticed.