Benjamin Marauder .22 transfer port 1/4 tubing

Airgun-hobbyist said:

I get the best velocity gains when porting and polishing the transfer ports by simply blending and radiusing the sharp drilled corners of the ports. High pressure air needs a smooth flow to increase velocity, so the air isn't going around a sharp 90° corner. I use a Dremel tool with small carbide ball shaped cutting bits to knock off the corner edges, to essentially create a curved pipe for the air to flow through.View attachment 488633View attachment 488634View attachment 488635

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