I went out to the range with the new Tikka 7mm08 yesterday. I did a short break in procedure with 4 shots then went to shooting groups. It shoots!
First picture is Hornady American whitetail. The four extreme outliers are the break-in shots. The stuff in the ~1.25" group includes a fouler shot.
The next picture is Hornady reduced recoil. There's 6 shots in the big hole on bottom. The three high shots had very stiff bolt close.
Not pictured is a few rounds of federal fusion, which the gun certainly didn't like.
I am pretty sure this gun has a short freebore for some reason. There were a few rounds on the American whitetail that had a stiff bolt close, and the reduced recoil all had stiff bolt close. The three reduced recoil fliers had a really hard bolt close and I had to put a bit of forward pressure on the bolt to close it. If it is a short freebore, the different poi for the three reduced recoil would make sense since those would be jammed farther into the lands. There was no stiff bolt close with the federal fusion.
I swabbed the chamber to make sure there was nothing in there as well as made sure the bolt face was free of any debris. Still stiff close. I didn't think to eject a chambered u fires round to look at the bullet to see if there was any markings from the lands. I was thinking it was a headspace issue.
I unfortunately shot all the cartridges, so I didn't have any loaded ones to make measurements on when I got home. And now I also don't have any to chamber to see if it leaves markings on the bullet. But I did take the cases, deprimed a few, and measured their base to datum with my comparator. The federal fusion, which closed very easily, had a longer base to datum measurement than the two Hornady! Also, all the fired cases chambered very easily, so I know the chamber headspace is just fine. Since I've been having the kids practice with Hornady reduced recoil, I'll be able to see if it leaves any marks on the bullet next time we go shoot.
Does it sound like a short freebore? I just can't win with my kids' gun! At least it shows it will shoot well, so it's definitely useable. Since I load my own, a short freebore shouldn't be a problem unless I want to load long heavy bullets. But I won't be doing that for my boys. But, I'm now afraid to buy any premium hunting ammo for fear that it won't chamber easily enough for a hunting scenario! I did kind of want to find a good factory load for it so I can focus more on bowhunting. Tikka has a 2 year warranty, so I could just send it back to them after season.
On a side note, when a rifle has a chamber that is within saami spec for headspace, etc but has a short freebore, how does that happen and how is it remedied?