case prep

I've noticed some resistance on my bolt whilst closing it. I had my die set as per manual, had played with it a bit and found a sweet spot where bolt closes like butter. However I then noticed the crimping on the neck has a much smaller area (left case) compared to the case on the right that...

As title says, anybody used (small) stainless steel nails whilst wet tumbling, any pitfalls I should think about? Thanks in advance