Word of warning first........... If the fore-end is tight and you can't get it off, that because it is MEANT to be tight. It is drawn up at the rear, between the ever tightening taper of the butt socket and the draws (hence the name.....) To remove it, NEVER, never, never, not EVER pull it away from the muzzle end, ever, never...........
Gently drift the rear end downwards gently using a wooden drift, side to side, on the top rearmost surfaces of the fore-end
Peter Laidler, REME Armourer, RNZEME workshops, Ngaruawahia Ordnance Depot, 1967-8