Getting the roll pin and gas tube out

[justa22]

Installed a free float handguard on my rifle, took about an hour to get the roll pin and gas tube out of the ugly factory railed gas block, was determined to save both for my new low profile gas block. Kept heating the gas block with my hand torch, then quenching in cool water, used penetrating oil on it , drove the pin back an forth till it came out, worked the tube by hand once it started to come loose. No damage at all, pain in the -------. It can be done!

 

[M&P10 owner]

Roll pin bore hole

Look very closely in the roll pin bore hole before you attempt to remove the pin. You'll notice that the roll pin hole is slightly over-bored for a short way before it narrows to the actual roll pin bore. You might say it's a stepped bore on both ends.
I'd say most folks having problems removing this pin are using too large a drift punch.