Please be aware there are (at least) 2 different front sight setups for the Lee Enfield.
If you have the type with the reverse screw then you need to losten the screw, not just smash it with a hammer.
If you have the friction with no screw type then tap with a drift if you must, but a sight pusher is much better.
Hammer, good!................. Mongo like hammer!
Allan Quatermain: “Automatic rifles. Who in God's name has automatic rifles”?
Elderly Hunter: “That's dashed unsporting. Probably Belgium.”