That's just what some guns do. My mossy will throw federal 2-3/4" rifled slugs about that high. It makes it more "pinpoint" accurate as you can "aim to the 6 0'clock". Put the bead under the spot you want to hit and squeeze the trigger. You can see the spot you want to hit this way other that putting a huge bead in front of it.

Or you can just try different brands. Each brand of slugs will shoot a little different.

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