I tried that. How hard does this need to be done?! Lol wow... Alright. I'll try again when or if I decide to change the rail.
It helps to have a partner, one to pull down on the delta ring while the other removes the handguards, or rail in your case. That Troy rail fits very snuggly around the barrel nut, one of the reasons why it's so solid, but can be a bit of a pain to install and remove, especially without 4 hands.
NRA Certified Pistol Instructor & RSO, IDPA Sharpshooter, Project Appleseed Rifleman
Member NRA, GOA, SAF, VCDL