Keith H, at the 100 Mile Clinic, one rifle experienced the same problem. I checked and compared how tight his op rod was in its channel against several others. It was very sloppy when grasped at the mid-point of travel and rocked from left to right. This is easiest to see with the op-rod spring out. Remove it, then reassemble and watch.
One thing that became clear at the 100 Mile Clinic was that rifles built close to the same time can vary greatly in their parts fit and finish. There were serveral explanations given such as depleting inventories etc. The point is you have bought a product that is assembled from parts made in more than one factory. There is no Consumer Reports magazine to rank them like Hondas and Toyotas. Your warranty is basically one second or one shot.
Now some gunsmiths weld up the small tab at the rear of the op-rod when they get worn out. This involves a good welder and understanding of heat treatment afterward. One hopes that the action rails are harder than the op-rod, therefore the wear will all be on the rod.
If the rod is sloppy at only one worn spot on the rails, your action is faulty. Making the guide rail tab thicker will only bind it elsewhere in its travel. One then needs very sophisticated work, or a new action. Matching the action's rails to the tab would lead you into needing op-rods with custom thick tabs. Forget that.
Your op-rod may just be very loose at the top where the roller goes when the bolt opens. Again either welding or replacement seems in order
With the thousands of M305 rifles now in Canada, and the nature of our relationship with the US, we more than ever need M14-specific gunsmiths. We need to be able to get them repaired in Canada. We also need a domestic source of spare parts to free us from border shenanigans. Some parts, such as the metric threaded ones I doubt the Americans will care to make. We are on our own. Where are our Canadian manufacturers?
Another possible fix for Keith H's rifle is a different op-rod. I doubt you will find anyone with a rod too tight in its channel, but if you do, try switching.
Try getting a new one if possible, good luck especially a Norinco part. Canada Ammo may have one. If not we're back to the border thing, but it's not impossible.
One last thought. If you have a rifle with some sloppy parts in it, you particularly need to err on the side of excess lubrication. Read the stickies.
