Extraordinarily advanced and with slab-sided sci-fi looks, the USS Zumwalt is a seriously advanced piece of military technology. Except when it . And requires to fire a single round from its big-ass gun.

Evidently, $800,000 for each Long Range Land Attack Projectile round for the Zumwalt’s Advanced Gun Systems was a price that even the United States Navy couldn’t justify. So it wasn’t clear what kind of ammunition the destroyer would use instead, until now.

Raytheon’s Excalibur guided artillery round could be the potential replacement, reports . The Navy didn’t confirm any details, saying that things were still “predecisional.”

But in a statement, Captain Thurraya Kent toldUSNI News that the Navy is still evaluating hyper-velocity weapons for the gun:

“The Navy continuously monitors the gun and ammunition industry capability and capacities. To address evolving threats and mission requirements, the Navy is evaluating industry projectile solutions (including conventional and hyper-velocity projectiles) that can also meet the DDG 1000 deployment schedule and could potentially be used as an alternative to LRLAP for DDG 1000.”

The Excalibur round only has a 30-mile range, about half of the LRLAP’s range. But they are also only about a quarter of the price.

If the Navy decides to go with the Excalibur, it will need to re-tool and re-engineer the AGS on the three battleships so that they can accommodate the new round, an endeavor that could cost $250 million alone.

points out that a new type of Excalibur missile, the Excalibur S “has a semi-active laser seeker. Once fired, the shell can home in on a laser painting an enemy target.” This would make it useful against enemy ships.

The shorter range also means that the Zumwalt will only be able to fire when it’s much closer to the coastline, however. Which increases the risk of it being hit by enemy fire.