Hey guys, I have an issue with my brand spanking new URG, however I brought it to the range today to zero it.

It is a DDM4 URG with 10.3" barrel, 1/8" twist, pistol gas system.
i put a B&T compensator (for the Rotex II suppressor) on it.

I am shooting 200gr L-tech and 200gr DRT Terminal Shock subs. Both are keyholing at 25 yards, some steering far off but most hitting in decent groups - but at an angle.

The barrel _should_ be able to handle 200gr, reviews on the upper indicates so, and a friend with an identical upper shoots 220gr without issues.

It key holes with and without suppressor attached to the compensator.

What could be the cause? Did I get a bad barrel or could the comp be the culprit?

It could be a defective barrel, and more than likely is, try a different comp and see what the results are, have you tried any supersonic rounds through it? If not regardless you should contact Daniel Defense, I know it sucks to send it back and wait but hell for the price you paid DD should make it right, and hope they do, from the sounds of it I doubt it would be the comp.

Easy test is remove the comp and try shooting it with the bare muzzle.  If key holing continues after that, I'd contact DD.

As others have said, test it without the comp first. If it continues keyholing, DD has already said they'll take care of you.

While I don't own any DD products this is a reassuring gesture, considering this isn't even in their sub forum! Since the Block III has come about with the Geissele Rails, does that mean we will see civilian production of RIS II rails again? Sorry to take it off topic real quick. Hey OP once again, I would just take the offer that DD has given you, so its' properly diagnosed and fixed!

Thanks guys. And a lot of thanks to Marler5811 for stepping up.

I'm going to the range this weekend to try w/o compensator and also a few different loads.

Being in Europe it makes this a wee bit more complicated.

Try putting something behind your targets to give them some support. I have a P-64 that I thought was keyholing rounds until I went to another range with targets mounted on backboards. There, all of the holes were perfectly round. Now when I go to the range where I experienced the problem, I take a piece of cardboard to place behind my targets. No more keyholes. I can only speculate that my issue was due to a low velocity round not punching through the paper but dragging it as the round nosed bullets made their way through the target.

Only guessing here, but hope you get it figured out.