Keep hitting the gun show circuits, flea markets, consignment stores and also ask your LGS shopkeeper if he has any odd ball loose rounds that he may want to get rid of.
There's this one seller called Clips n' Things (not 100% sure on the name) out of Goshen that usually sells collector ammo by the onesies.
Hit a LGS today and ended up having seven more rounds for my collection given to me. Two by a customer who I had helped with a gun repair in the past and five from the store owner.
Here is what I added to the collection:
.17 HMR
.222 Remington
.357 Magnum
6.5 x 55mm
7mm Mauser
7mm Remington Magnum
.338 Winchester Magnum
Nice start. It is an addicting hobby, I started with 16ga shotshells and boxes. I shoot a lot of 16 and am always looking for it. I let it be known around work I collect old ammo and people started coming to me with old stuff they got when relatives passed away and such to give to me to get rid of. One guy brought me several full boxes of western X and western Super paper hulls. The way my gun cabinet is set up there is enough room behind the long guns to stack the old boxes. I have not decided what to do with individual cases yet.
If live ammunition is shipped ground via FedEx, UPS, ext.. it is not hazmat. If you ship it air then it becomes hazmat. Primed brass is not hazmat either. To ship ammo you need a Blue ORMD sticker on your box. NEVER ship ammo USPS = Felony
I am a licensed ammunition mfg. I ship regularly with Fedex.
MAJOR score for my ammunition collection today. Here is what I was given:
.32 Short Rimfire
25-20 Winchester
32 Winchester Self Loading
351 Winchester Self Loading
32-40 Ballard
303 Savage
I think you've got a great hobby there. Your collection is very cool. People on love to help, you should be adding several to your collection. Good job!