Best way to ignite myself for Elemental Projector relic?

I’m trying to find a good way of setting myself on fire to make use of my elemental projector relic, so I’m guessing some low level grenade mod or weapon, but I’m not sure what the best option is. Any suggestions?

Low level sellout pistol is the popular one

I’m partial to the COV AR legendaries. They all set you on fire