After the PC9/PC4 was discontinued, value increased on these, but not a lot.
Then, as the newer PCC was released a few years ago, the value of the originals plumeted. I have a very nice PC4 with a ghost ring. I've attempted to sell it multiple times, without a sniff. Part of the problem too, the folks at Ruger don't understand the PC9/4 and newer PCC are not the same gun. Try to find parts for the originals, and they will attempt to send parts for the newer version, and argue the parts are the same. There are no parts interchangeable between the originals and the later version. The problem in enhanced by the nomenclature. Folks insist on calling the newer model a PC9. The newer one is not a PC9. So folks see the older one and the newer one as one and the same. Why would a feller buy a 25-year old PC9 when he can buy a brand new PC9, not understanding they are two completely different guns. Ruger has followed suit with this confusion.
Bottom line, they have no parts, and offer no support for the originals. Hence, I've found them to be not easily sell-able.
On the other hand...
I've owned a number of the the original PC9's and PC4's. If a guy didn't bubba-fy his carbine, and/or otherwise lose parts, I can't imagine mine ever needing replacement parts. These are robust guns that have always worked extremely well for me.
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