With the exception of a major woodworking project, I don't count costs with my hobbies. When figuring expenses for woodworking projects, I don't add in costs of my tools. I figure I paid for 'em so I don't need to figure out a cost/hour basis on the equipment. I only figure out my wood & hardware costs and go for it.
I figure reloading is a hobby in itself, which lends itself to another hobby (shooting), so I get 2x the benefit from it.
If you track your other hobby expenses, by all means, track your reloading costs.
If your wife tracks your hobby expenses, perhaps a (GENTLE) reciprocal tracking is in order - watching the HIS and HERS side of the hobby ledger.
As long as you can afford what you're doing (i.e., living within your means), enjoy it. If your hobby is presenting a financial hardship, then tracking your expenses is critical.
Q