Free Mike's War: Sequel to Jesse's Starship by Saxon Andrew Page A

Tanks are smooth bore.” Howey looked at Jeanette and wondered how a woman knew so much about the weapons used by Earth’s military. She saw his expression and said, “My father was one of the highest ranking generals in the United States Military; of course I know about all the weapon systems used by all our services.”
    “We’ve cut rifling into them.”
    “Why didn’t you just use a cannon barrel that already had the rifled bore?”
    “The Abrams’ main gun was portable. Its breech could be automated for a belt feed such that it could fire at a much higher cyclic rate.”
    Jeanette’s mouth went into a pout. She stared at Howey and shook her head, “There is no way you can feed 120 mm rounds like a machine gun. The heat alone would melt the barrel.”
    “What is the temperature of open space?”
    Jeanette was surprised by the question. She tried to remember and Mendrel said, “It’s slightly higher than absolute zero. Cooling the cannons will not be an issue.”
    “How are the spent shell casings going to be removed?”
    Howey sighed, “That’s what we’re working on now. The belts have an empty space beside each of the cannon shells that is magnetized. The belt will move in line with the barrel and the injector system will push it into the barrel’s breech. Once the round is fired, the belt will move one notch forward and the extractor will drop the spent casing on the magnetic slot.”
    Jeanette nodded and said, “So what’s the problem?”
    Mendrel still had his head in the hole and his voice sounded hollow, “Carrying the spent shell casings takes away from the number of rounds that can be carried.”
    Jeanette looked at one of the new 120 mm shells that was standing next to the work table and said, “Why are you using the old propellant to fire them?”
    Howey and Mendrel both turned and looked at Jeanette, “What?”
    “I’ve been reading the properties of the explosive used by the slivers and it’s my understanding that it is as hard as steel until you spin it.”
    Howey nodded, “Yeah, go on.”
    “It just seems to me that you could take the projectile portion of the shell and use a much smaller base made of the new explosive. You put the shell in the barrel and spin it as it enters the breech. Now the base is active and once you ignite it, it will push the projectile out of the barrel and not leave anything behind.” Both engineers stared at Jeanette in silence and she said, “Hey, the normal shell casing detonates a large explosion of gunpowder to fire the projectile. Wouldn’t this accomplish the same thing?”
    Mendrel looked at Howey, “Could the barrel withstand the pressures?”
    “They do now. The issue would be the heat they would have to endure… but, if the barrels are in open space that would not be a problem.”
    Mendrel pulled out his pocket link and began punching numbers into it. After three minutes he looked at the result and showed them to Howey who began shaking his head. Jeanette watched them and said, “What?”
    Howey said, “Your idea is a good one. I thought the blast might set off the explosive in the projectile but it won’t become active until it has left the barrel spinning. Our tests have shown that the projectile won’t be activated until it’s twenty feet out of the barrel.”
    Mendrel nodded, “So the blast in the cannon’s barrel won’t harm it.”
    Jeanette smiled, “But you have to be able to spin the shell to activate the base; won’t that activate the projectile?”
    “No, we’ll make the two mixtures different so the base can be activated at a much lower RPM. Developing a device to spin the shell before it enters the breech is a lot easier than extracting the spent shell casings.” Howey smiled, “Thank you.”
    Jeanette curtsied, “Don’t mention it.”
    Mendrel said, “If you come up with any other ideas…”
    “How are you going to target the cannons?”
    “Just like the tanks did; you’ll point the cannons on the path