I can't let this one go without further comment. Is it really an "Archer" if it doesn't have the tapered tail? It looks like a Hotchkiss nose with rings on the tail. It was a terrible idea! Lead sabot too thick and heavy. Was this by design or a stupid mistake by CS foundry? Below is an identical 3.3 inch version from Shiloh. I believe that most of those dug have been this slightly larger caliber. No shell versions am I aware of. I suspect these were cast in Memphis by Quinby & Robinson. They made eight or ten 3.3 inch bronze Rifles during 1861. For a short time in mid-1861, 3.3 inch was the regulation caliber for CS field Rifles. By the end of 1861, the regulation caliber had been reduced to 3 inch. They also made some bronze 3 inch Rifles and their invoices confirm the production of hundreds of field-caliber "Archer" projectiles (including some big 24, 32 and 42 pounder Archers). A number of Deep South foundries produced their own versions of the Archers. I'm still working out who made what.
The second photo below shows a common flat-nose 3 inch Archer bolt made in VA and dug on the Shiloh battlefield. The State of Mississippi purchased 5,000 of these from Tredegar in April 1861. Identical Archers have been excavated in Manassas and Centreville, Virginia. This was the correct design for an Archer bolt. I suspect the Deep South foundry tried to make their own version of this VA projectile without removing the lead sabot to observe the tapered iron ringed tail. Just a guess.
Woodenhead