Get your dessicant at hobby shops that cater to those who dry flowers. A lot cheaper there.
Shipboard spaces are air-conditioned/heated, and the ammo is off-loaded before going into a shipyard period where those services are turned off. Inside temps on my ship in drydock reached 120 degrees - but we already had our munitions off-loaded.
In addition to our small arms ammo, our 5"/54 gun used separate 5" projectile and powder in an aluminum can that was consumed on firing - no brass casings to worry about! Our gun would throw the approximately 75lb shell about nine miles - up to fifteen miles for the rocket-assisted Extended Range shell. Accuracy was pretty good - our gunnersmates nailed a cow on the hillside in the Viequez Island range once - silly bovine shouldn't have been there.....