my ar-15 m4 carbine only likes metal case ammo double star m-4?

You need to get a "chamber brush," and use that brush and solvent to clean the chamber.

Steel cased ammo gums the chamber with lacquer, carbon blow-by, or both. This will cause cases to stick.

If you shoot steel cased, you will definitely want to bring a cleaning rod when you shoot. If you really stick a case you'll need to push it out with the rod, if pulling the charging handle and tapping the butt on the ground doesn't work.

Wrap some Scotch Brite pad around a cleaning rod and sock that up in a powerdrill. Dip it into some cheapo motor oil and then use it to polish the crud out of your chamber. It won't hurt the gun in any way. I shoot for five mins polishing the first time. If it still sticks, polish for ten mins the next time. Keep the pad moving in and out of the chamber as you work it.

Russian ammo is lacquered to prevent rusted casings. When your gun gets hot from firing, that lacquer heats up and sticks to your chamber walls. When you go back to brass cased ammo, it heats the lacquer up and it works like glue on the brass. You'll need to polish it out every time you use that Russian ammo.

You need to clean it real good.The gunk from the steel cases have built up and are cause the brass rounds to hang.

Educational opportunity:

Steel and brass are both metals.