Attached gas-check facts for kids

An attached gas-check was a special copper plate. It was fixed to the bottom of a cannonball, called a "projectile." This was used in older cannons known as rifled muzzle-loading (or "RML") artillery. Its main job was to stop hot gases from escaping when the cannon was fired. This helped the cannonball fly faster and more accurately.

Gallery

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  1. This is a Palliser Shell, designed to break through thick armor.

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  2. This is a Common Shell, used for general purposes.

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  3. This is a Shrapnel Shell, which burst in the air to scatter small pieces.

What is an Attached Gas-Check?

An attached gas-check was a clever invention for cannons used a long time ago. Imagine a small, flat piece of copper metal. This piece was firmly attached to the back of a cannonball. Its purpose was to create a tight seal inside the cannon's barrel when the cannon was fired.

Why Were Gas-Checks Needed?

Older cannons, especially those called "rifled muzzle-loaders" (RML), had a problem. When you fired them, hot gases from the exploding gunpowder would try to push the cannonball out. But sometimes, these gases would leak around the sides of the cannonball and escape. This leakage meant the cannonball wouldn't go as fast or as far as it should. It also made the shot less accurate.

How Did They Work?

The attached gas-check solved this problem. When the cannon was fired, the huge pressure from the exploding gunpowder would push on the gas-check. This pressure would make the soft copper plate expand outwards. It would then press tightly against the inside walls of the cannon's barrel. This created a perfect seal, stopping any gas from escaping past the cannonball. All the power from the gunpowder was then used to push the cannonball forward, making it fly faster and straighter towards its target.

What is RML Artillery?

RML stands for "Rifled Muzzle-Loading." Let's break that down:

• Muzzle-Loading: This means the cannonball and gunpowder were loaded into the cannon from the front end (the muzzle). This was different from later cannons that loaded from the back.
• Rifled: This is the important part! Inside the barrel of these cannons, there were spiral grooves, like the inside of a screw. These grooves made the cannonball spin as it flew through the air. Spinning made the cannonball much more stable and accurate, just like a spinning football flies straighter than one that tumbles.

RML artillery was a big step forward in cannon technology during the 1800s. They were used by many countries, including the United Kingdom, for both land battles and on warships. The attached gas-check was a key part of making these powerful cannons work their best.

See also

• Gas-checks in British RML heavy guns
• Automatic gas-check