Exactly it’s the chamber pressure.

But most argue about a Llama Extra in 9 mm largo. Some shoot any round that fits it. Even the shorter 9 mm x 19 letting the extractor head space the round instead of the barrel. Or they shoot 38super. Just an example food for thought.

Hmmm letting the extractor headspace the round there’s an idea?
But think with a knotched cam opposite the extractor. Not just thinking out loud.

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Plant garlic in the fall