Be sure the rifle's empty
And remember to slide the mag tube out after removing the forend iron/band screw(s), and before trying to pull it off.
Start the mag tube removal with it's front end plug screw - and be mindful of the spring pressure on the cap.
Some forends may be pulled off/down w/o removing the mag, depending upon how the barrel/tube combo was inletted, but if there's a partial wood web between the two channels, the mag will have to come out.
Also take care that the metal forend hanger, inside the front end of the wood in a barrel under/dovetail, doesn't catch on and/or split the end of the forend wood - it has sharp egdes/corners.
A lotta force generally isn't needed.
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