New 45-70 AW already going back for warranty work.

[Flinch]

Or I would use a punch to thicken the edges of the dovetail on the front sight

What you are referring to is called 'staking' the front sight.
Typically this is done by securing the front sight (bottom up) in a vise with small blocks of hardwood with leather to protect the sight.
Then the base of the sight is given a few punch marks to create some metal expansion to tighten the sight in the dovetail. This way it is invisible with no damage to the sight. Pretty basic (and common) procedure.

A good reminder here when looking over a new gun prior to purchase is a quick, firm push on the front sight. A sight as loose as the OP reported on his rifle it would have probably moved with finger pressure.

I picked up my new Golden Boy after reading this thread and that is exactly what I did to check the front and rear sights before accepting delivery.

When I adjusted windage, I did not have to tap the rear sight very hard to move it. I could not move it with my fingers before I tightened the lock screw, so I am not worried about it.

[bmur66]

I would guess that your rifle was not the only one with this problem and the service rep already had a good idea of what was needed,

[medpilot]

I recommend sending it back to Henry. I was given a Big Boy 357 for Christmas that wouldn’t cycle well and jammed a lot. I got it back 6 days later (only, six days!) and it’s perfect now. Best warranty experience of my life. I bet yours will be perfect too.