Hello there, I see this is your first posting and that your new to the forum. Welcome from Missouri.
To get a much better identification on your bullet you need better measurements. Tbe bullet needs to be measured with a caliper either a dial or digital one, and weighed with a scale that weighs in grains versus grams which would be used to weigh precious metals. If you have a friend or an acquaintance that reloads their own ammunition that is the person you need to see.
Just at a very rough look it appears it may be in the quarter bore area, .25 or .26 caliber such as a 6.5 mm that uses a long bullet for caliber. The 6.5 Sweedish with a lead 139-40 grain bullet would be only one example. Anyway use a scale that weighs in grains and measure below that crimping grove with a caliper and cross reference in a reloading manual. Hope this helps, good luck and happy hunting.
Don