coolbreeze

I don't own an M4, but typically, to remove a shotgun stock, you start by removing the recoil pad. Trigger group isn't involved. Good luck.

My Sport II is a 20ga, before shooting, I cleaned down to taking the bolt apart and removing the trigger group. I lightly re-lubed and took it out and shot it. No issues at all with 2 1/2 Dram, 7/8 oz target loads. Good luck.

Sorry, no photo, but just a brass cleaning brush on a cleaning rod with no handle, chucked to my drill. Works slick.

Hoppe's on a brass bore brush and my cordless drill. No problem.

I just bought a Sport II in 20ga. for casual skeet and clays. So far, I love it.