Help with determining OAL (to lands/ogive) 6XC

[Michael C]

I have never had such a hard time determining my Base to Ogive measurement in any rifle I have ever reloaded for. This thing is driving me nuts. I have been using that tool on 4 other rifles for over 10 years. I am new the 6XC but, have loaded for my other prone and Palma rifles and my service rifles.
I have used the Hornady tool (both curved and straight) and cannot seem to get a number that makes sense. I got this 6XC rifle used and the last owner gave me his measurements and the 105 Berger is seated quite deep. I posted last week about some donut issues with the brass that came with it and lots of people said to just seat above the donut. So today, I have been messing around with the Hornady tool and a dummy cartridge that I seated a bullet into (no powder or primer).
When I seated a bullet long so that the top of the boat tail sits just above the donut area, I can close the bolt on the dummy round, extract it and it measures the same. I did so several times and the bullet never stuck. I assume that I am not hitting the lands but, I am not sure. However when I use my tool, it has me seated so deep in the case that the bottom of the boat tail is past the shoulder. What the Heck? It just does not make sense to me. Why would the throat be so short in a single shot prone rifle?
I have fired the cartridges at the shorter length in a Palma match a few weeks ago and they shot well at 800 and 900 with good X count. It started blowing like heck and I was all over the place at 1000.
Anyone have any suggestions to try? Mike

 

[DeadEyeDick45]

 

[jdh47]

Wonder what the round count is on the barrel. It might be prudent to look at it with a bore scope.

Joe

 

[mikecr]

When I seated a bullet long so that the top of the boat tail sits just above the donut area, I can close the bolt on the dummy round, extract it and it measures the same. I did so several times and the bullet never stuck. I assume that I am not hitting the lands but, I am not sure. However when I use my tool, it has me seated so deep in the case that the bottom of the boat tail is past the shoulder. What the Heck?

The hornady tool relies on shoulder datum, right? Is the dummy case formed to the chamber? Forget the Hornady anyway.
You know you don't want to seat bearing into donut, so don't. Seat bearing out further until it is soft seated with bolt closure.
Back off the load, and perform seating testing from this point, adjusting further from jammed, until identifying best seated CBTO.

 

[Nomad47]

Have you tried pushing fairly hard on the Hornady plunger? It sounds like the bullet is hitting a tight spot when in the tool but overcomes the tight spot when seated in a case.

 

[Michael C]

Dead Eye, I am heading out to the shop to try the technique in the video above. Thank you...will advise.

 

[DeadEyeDick45]

Thank Alex Wheeler

 

[jlow]

I have had a very similar experience doing the same thing with a Berger 140 Hybrid. This drove me nuts until I figured out the problem with seating the bullet deep and pushing it forward is because the bullet is so long and narrow it was getting stuck cockeye in the case. When that happens, you feel it stopped moving forward and think it is in the lands when in fact it is just stuck in the case.

Seating the bullet long and pushing the case into the chamber to seat the bullet is in fact how I got it to work. In your case, it may well be that you have a very long freebore.

What I would suggest you do is to first forget seating short – it does not work with this type of bullets. Seat it long, push the modified case (I assume you are using the Hornady tool with a modified case...) with the bullet into the chamber by hand, now push with the rod on the bullet to see if it falls out. If it does, then you have a very long freebore and will have to do a long jump. If it does not fall out, you will be able to find touching distance reproducibly.

Good thing is you never have to worry about the donuts

 

[Michael C]

Well, I used the technique in the video above... short throat. Thank you to all that helped out. The good news is no more guessing where to seat.
I just can't figure out why a single shot prone rifle in 6xc would have such a short throat. It reportedly has 1500 rounds on it. It was a good price and really I just paid for the action and eliseo stock. I will see about a new barrel soon.

 

[jlow]

When I seated a bullet long so that the top of the boat tail sits just above the donut area, I can close the bolt on the dummy round, extract it and it measures the same. I did so several times and the bullet never stuck.

So how can this be too short a throat?