I as at the range today and noticed my rounds would not chamber. I broke tthe rifle down and after a quick look did not see any issues with the barrel. Loaded another mag and had the same issue. I broke it back down to run a patch through and promptly broke the cleaning rod. When I got the rod out the upper half of the casing came wth it. I have never seen anything like this and I am wondering if anyone has and what cold cause this. Any help or insight you can offer would be appreciated. Thanks.

Sounds like a case head seperation. Usually happens when using shit ammo made from surplus brass fired in a machinegun.

It can also happen with too much headspace, which sounds unlikely since it has run fine before.

It was Remington UMC 55 gr soft tip

Remington UMC has a reputation for problems.  Avoid it when possible.

Quoted: Remington UMC has a reputation for problems.  Avoid it when possible.

Indeed it has problems, but like any ammo, the user should visually inspect rounds when loading them.

I've shot a fair amount of Rem UMC 55gr with no problems. I have often noticed that the seating depth of bullets is not very consistent -- some rounds have a few millimeters of cannelure showing.