Cold Bore shot way off

[nrpate05]

Hey all, thought I’d throw this out to the pros on here. The last couple times I’ve shot my 25-06, the first cold bore shot is way off. In the picture below you’ll see what I mean. The subsequent shots are decent and are grouping how this rifle usually groups. Curious what’s going on. Point of aim is the lower left corner of the red square. My internet research says a bedding issue? Thought??

 

[elkantlers]

Is the cold bore with a clean barrel?

 

[Jnasa]

How long has this been happening? Approximately how many rounds have been fired?

If you shoot a second group is the first shot drastically off as well?

As Elk Antlers asked is it a clean bore each time?

 

[D4570]

I have a Marlin 4570, an actual Marlin. Anyway, the first shot cold is always 5" high, but only when cold. It's perfectly straight up and down 5".I tried everything, multiple loads and bullets. Clean fouled everything. Nothing helped. It's a lever gun, so bedding is not an issue. What I did was sight it in to the first shot; it takes all day to sight in, shoot, let cool for two hours, and shoot again. It will shoot a cloverleaf group with the first shots and a cloverleaf after that, but 5" low. These are not low-velocity lead bullets; they're 300 gr Hornady 2500 fps loads. Seldom do I need more than one shot, but if I do, I have to aim 5" higher. It's not a big deal if I keep the shots around 200 yards.