The combination of self assembled rifles and self assembled ammunition by individuals who don't have a thorough understanding of either one often results in posts exactly like the original which began this thread.
[bleep] Off! You have no idea anything about me. I purchased a complete upper, so if it has headspace issues it isn't because of me. But that isn't the point. The ammo I use has all been reloaded by yours truly for at least thirty years. I bought up some of this cheap fmj [bleep] for ripping off rounds through these tacticool rifles for fun. My mini-14 fired the same ammo the AR had issues with. So maybe the ammo is the issue with the AR. I openly said it. But if everything fired fine out of everything but the AR does it or does it not make it more finicky?
So as I did load some with a Lee kit it may be the culprit. If you've done anything at all in life for yourself, at some point you may have something not go exactly right. Insulting people is pretty low. It's easy to talk [bleep] when you're anonymous.
Thats teh way to deduce an answer, insult the folks that have answers, and by bad language too. Not welcome here, to me at least in that usage.
Anyway the mini is goign to have a sloppy chamber compared to most ARs that nowdays have snug chambers and are more accurate because of it.
ANYTIME you desire more accuracy you go to a better chamber and barrel. That negates using any old ammo you can find, reloaded or not. Try putting any ammo in a BR gun. Duh.
Now that you've admitted you loaded with the Lee kit, it does infer that you do not know that much about loading or guns if you expected neck sized or any old ammo to work in any old gun.
The post was not insulting, it was spot on IMHO. If it was insulting it would have used the same language you did.
And the poster was not, IMHO, even being specific to your situation, just a generally correct over all statement.
IMHO if you want it to go bang with anything all the time you need a mini or an AK. I just don't tend to like, want or often keep a rifle that won't shoot MOA. Same with ammo.
I have no "blasting" ammo as I'm not sure what the use of that ammo might be. If I want to make a lot of noise its been cheaper to light off a full string of firecrackers. And somewhat safer too.