Quoted:
A brass punch will not work. You need a hardened steel punch and the whole assembly cannot have any give when you hit it, it must be planted firmly.
I dont know why, but all the DIY threads dont specify the punch type. Use a hardened steel punch. Even a plain black steel punch will not work, you need it to be hardened so when you strike it, all of the hammers momentum transfers to the pins.
A big +1............also, you have to use something really solid on the back side......such as a piece of granite or steal plate w/ a socket against the back of the gas block where the pin would come out (no wood), hammer should be steal too.
Any give what so ever would render efforts useless, so dont do this on your bedroom floor (it gives)...........Use a really solid bench on the corner where the leg is or go all cro-magnon and use the garage floor.
You'd be suprised how little effort it takes w/ a solid system..........system being: hammer to punch to pin, gas block to socket to steal plate to garage floor, no give !!.............even a brass punch has give, so yea, use hardend steal.
Oh and my pins came out w/ a 4ounce hammer......I know, I was probably lucky