I thought I did, but I only looked at my first few comments so I didn't see it.But in Post #13 you mentioned it was a custom rifle.
Good tip. I'll try that.Anytime I have an issue with a round not chambering I will get out the premanent marker and color the entire case and bullet.
Insert it and see where the problem lies.
You will see where the issue is at when you see where the marker has been rubbed off.