Mini 30 POI and Accuracy

I didn't want to hijack Pointer's current "Mini Medicine" post, hence this new one. My Ruger Mini 30 consistently shoots 4-5" low at 100 yards on the first shot and then follows up where I'm aiming for the next several shots. These rifles have a reputation for poor accuracy, but my follow-up shots will usually give me 2-2.5" groups with good ammo, which is plenty good for a short-range hog rifle. We know that accuracy will deteriorate as the barrel heats up, but that can't be a significant issue after only one shot. I have heard some AR's can have the same problem with the first shot, although I have not experienced that. Can it be that the rounds are not chambering the same when the bolt is released on the first round, compared to the action slamming the bolt both ways on subsequent shots? I have thought of a "fouling shot" when the rifle is first loaded, but that's not always practical. I could sight in for the first shot, but then follow-up shots would be 4-5" high. Is there a solution? Is there some other explanation?

That is what I've seen Chad explain is the case. I learned from him, doing load development to load two extra rounds. Throw out shot 1, shoot three to five, and leave one extra round in the Mag to be chambered but not fired. That is so the bolt does not lock open on the last shot in the group.

I have observed this situation on my own LR-308. Shot #1 might be .2 Mil lower than the next shots. The key is to "know" what the rifle is going to do, and it looks like you know. So you can adapt to it, and hit what you want to hit.

Fireman, thanks for the feedback. I like that solution for shooting at the range, but the "Throw out shot 1" idea may not be practical in a hunting situation. If I could only train my brain to aim high on the first shot...

You can.