Since I started with a 16" Big Loop .357 Carbine, my button mag conversion oughtta qualify as a half mag.
I used my $1.29 hacksaw, to shorten the issue mag tube; my $4 Chinese milling machine (file) to cut a female dovetail in the barrel bottom to accept the forend cap hanger; and my plastic to buy the forend cap/hanger & screws from a parts house for about $17.
I handmade a slightly large-headed screw, to retain the mag tube in the forend cap's inside groove under recoil & mag spring pressure.
OH...... and, I had to slightly rasp down the forward couple inches of forend wood, to be flush with the new forend cap, stain the area to match the rest, and apply stock finish.
It's probably not the way to do it, but whadda I know ?
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