I have a new Ruger MKII 77 in 6mm Remington with feeding issues. Doesn't feed in CRF mode, more like a push-feed. Any options,or need send in for facory repairs?Have only tried remington factory ammo so far......

I would first check the magazine follower is operating properly. As the round is pushed forward, the follower should spring the cartridge up and the claw extractor should engage the rim (case head). If it is not doing so then it isn't working properly. Make sure the magazine follower is springing level and smoothly.

Something simple as improper tension on the extractor can cause this. If there is too much bend in the tail w/ too much tension, it will bind and the cartridge head will not immediately snap behind the claw against the bolt face as it clears the mag box. Too little tension and it will drop out.

A burr or rough suface behind the claw and/or at the bolt face can cause binding as well.

If the follower and/or the cartridges snag or bind w/in the mag box, you'll have all sorts of issues. The follower/cartridge(s) must smoothly and freely move up and down w/in the box. As you are stripping the top round out of the mag box, the follower and rounds below it must smoothly give way slightly while maintaining even upwards pressure. Any binding in this movement can prevent the cartridge from smoothly being pushed up behind the claw. If it binds badly, you can jam the cartridge between the rails and the cartridges/follower below. Often the box has burrs along its joint and/or the follower is rough along its edge. The mag box could be bent or not properly assembled in the rifle so that it is cocked and binding between the receiver and bottom metal.

Many simple things can cause this alone or in combination.

GVA

Yeah, I had a new one that did that. With the bolt out, see how much force it takes to snap a round under the extractor.

The previous response gives a good mechanical description of what's going on. Since the extractor is so snug, the cartridge enters the chamber at too steep an angle and jambs - am I right?

I don't know the easiest way to fix it, I sent mine back to Ruger (also had a loose one go back). Remember this experience next time someone extols the virtues of CRF.