Why would they be wonky? They work fine
Some shooters feel that fresh ammunition is in order. A friend of mine once gave me his 10 year old ammunition. He said he'd carried it around long enough, and just bought a new box.
I used them for target work, no issues, but I did not use them for hunting. His feeling was that bullets, and ammo can get old, and have issues. In reality this doesn't happen often, or it isn't noticed. I've had experienced shooters tell me instances of old bullets failing, one I remember was of loose cores, he noticed that several bullets rattled when he went to reload them.
The silvertip was a tri-metal bullet, gilding metal, lead core, covered with a tin or aluminum cap. I suppose, that under certain circumstances this combination of metals may lead to some bullet compromise. Somewhat akin to hydrogen embrittlement or ???
Luckily 30-30 ammo is pretty inexpensive compared to some other calibers. Use up the old silvertips for sighting in, blowing up milk jugs or ??? and buy some new stuff for hunting.
Sorry can't tell you why they may be wonky, just that I believe there is a possibility that they might be wonky. Wonky enough to notice at 30-30 ballistics, perhaps not.
BTW; A friend of mine that used the old silvertips in 308 Win, switched to the new stuff, his comment was, "Work the same, still good".
