The question of buying collector ammunition as an investment comes up from time to time. This is easy to answer. DON"T.
Buy collector items bcause you want to own them. If they increase in value it is a bonus.
The cartridge market is VERY small and specialized. Most cartridges are worth very little and the ones which are rare and valuable are too risky to be considered as investments. Add to that the wild cards of new laws , natural decay , thining of the major collector pool which reduces the retail value of rare items and at the same time adds collections to the market further reducing value.
Some items you will only see for sale once in your lifetime but most you will see over and over again. Buy the ones which you like and can afford without creating family problems.
Establish a budget and stick to it.
Try to specialize. There are far too many cartridges to be had for general collectors and in any collecting field knowing a little about a lot is not as good as knowing a lot about a little.
BUY REFERENCE MATERIAL. A $20 book can save you hundreds of dollars. IGNORANCE is expensive. Recently on ebay a hand full of folks bid up a hand sectioned $20 flechette cartridge to well over $100 and I saw a .45 ACP with ECS headstamp for sale at a huge price identified as made for GERMAN paratroopers in WW2.
Most of us have shells which we paid too much for when we didn’t know any better. The quicker you get to know better the more enjoyable your collecting will be.
If you have money to invest and are not an INVESTOR put it in triple tax free bonds NOT collector cartridges.