Can a corporal in a team leader position have me do corrective action (“smoke” me)? And was I wrong to tell him to eat a bag of dicks?

I assume this was a training environment. Training is where everyone gets trained, including the NCO's, especially dry training, that is where mistakes can be made, evaluated, reflected upon. The simple solution would have been to have a sidebar, explain yourself respectfully, and failing that, you then go to the squad leader. Getting into a pissing contest, regardless of how right you are, immediately puts you in the wrong. He is the NCO, you are not. The minute you refused to obey, and then told him to eat a bag of dicks lost you any moral, professional, and situational high ground. You should have either pulled the TM to show where he was going wrong, or requested to see the squad leader. Hell, if no rounds were being sent down range, you could have stated your argument, let him make his mistakes, and waited for the AAR. You subverted his authority, disobeyed an order, and disrespected an NCO. All 3 are separate infractions of the UCMJ. Two wrongs will never make a right. I have been in your shoes SPC. The first time, I did as you did, and paid mightily for it. The second time, I learned from the first, and asked for a side bar, explained myself without the arrogance or derision, and the matter was amicably solved.

When I was a Corporal. If you came back and said something like that to me. I would have started UCMJ proceedings against you for insubordination.
You are completely in the wrong here troop.

Simple.... "what if" you were a Corporal and you told someone to do something and they gave you that response? Don't play the "But this" game... only facts... you're a Corporal and you asked one of your Soldiers to do something and the response was eat a bag of #$%s.... Your response?

Being realistic, everybody has to start somewhere to learn how to be a leader. In this case, both of you have responsibility. Your corporal‘s responsibility is to learn and grow as a leader whereas your responsibility is help teach him how to be better. I dealt with the same situation many times, it was very difficult because no one was really sure what to do. Reality goes that regardless of rank, you guys need to rely on each other for help and support, especially when shit is hitting the fan. I dealt with many people that were promoted to corporal that had no business being in leader ship, with disastrous results. However each person adapts to positions in their own way, a true team will help build on the weaknesses through education and coaching versus telling each other off.

Yes! Full stop! As one person stated you speak offline and resolve. Full stop!

If he's your team leader, then telling him to "eat a bag of dicks" was wrong. You may well know more about how to operate a mortar. But you don't address your team leader that way, whether you're more experienced or not.

Well, it's never a good idea to tell anyone to eat a bag of anything....new Corporal was wrong for not listening because he needs to learn from those already doing the job...and You were wrong for giving into your ego instead of your professionalism.

What does 'smoke' mean?

A bag lol

He might deserve your comment but he still is a noncom! In my day I would have made you eat that bag and would have had the support of my entire chain of command. In the military seniority doesn't count though a good leader will find a way to incorporate authority with common sense, shut up and learn from those who have the experience. Still, he out ranks you and as a noncom you deserved to be put down. You're in the military boy quit acting like your privileged. Embrace the suck it will make you a better man Instead of a wimpy sniveler. Most people in today's military wouldn't have made in my day. When you had a disagreement with your noncoms and didn't like the treatment, you embraced the suck or took it behind the barracks got your whooping and the went had a beer. Not today with stress cards and all the wokeness! You're always going to have someone above you that knows less than you, teach them that you're a better man by embracing the suck. They will get it if you go into combat.