We got ahold of the folks that make these new SLAP SHOT PHD shells and they offered to send us some to test out. They claim they have a 3000 fps velocity which is probably the fastest 12 ga. slug in the world. They are for rifled shotguns only.
To find out more about these and purchase them slapshotusa https://slapshotusa.com/products/12-gauge-personal-home-defense-phd-250-box-of-5
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