Inspect your brass closely.
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Don't be complacent, regardless of brand name. Due diligence is required. I've seen plenty of "bad" batches of brass. Even lapua, many many times. Just a moment ago I finished sizing a batch of 150 6BR cases and found 2 cases with creased necks. Lapua is certainly not infallible, and others are usually worse.
The one on the left was a creased case I didn't catch when it was brand new, and upon firing, split all the way up the neck. The one on the right you can just barely see, is creased on the shoulder. Within a firing or two, it would probably split too. That is not happy for a nice chamber.
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Another example of a piece of brass that I will cull. Nosler(norma) 17rem brass here. For some reason the case on the right exhibited odd markings after annealing. It was very clear that the markings were more than surface deep. I could speculate as to why those markings showed up, but that is all it would be; speculation. The point is that it was the only piece of brass that was different from the rest. All the others looked like the brass on the left. It is important to pay attention to little differences like this and understand that inconsistencies can come from any number of variables during manufacturing. All pieces are not created equal, and it is not uncommon for employees to pick up stray brass and throw them in the mix. These cases should be culled, or at the very least, separated. They can come in handy for random testing where brass will be sacrificed.
Here is another 17rem case I found with a creased shoulder/neck. This was the 2nd firing... so I missed this the first time through.
