6BR bullet seating question

[earthquake]

I am attempting to load ammo for my Am at the GAP Grind next month. He will be using my 6BR. I only got this barrel for fun or my kid to use and haven't loaded anything but 95-TMK's with it so far.

For the Grind though I'm going to load up Hornady 105 BTHP's in it. When I was measuring Base to Ogive in this barrel, it seems....off. The BtO measurement is 1.60" on average and it looks like these bullets are waaay down into the case. Is that normal for 6BR? If I go with a standard start point of a 0.020" jump, then they're even farther in.

I'm used to my 105 Berger hybrids sitting out a lot farther in my Dasher. I know they're different bullets, but damn!

Does this look right?

Here's where the bullet sits in the case when touching the lands.

Dasher for comparison.

 

[blbennett1288]

1.645 CBTO is what I run with 105’s

 

[Dthomas3523]

Reamer with short freebore.

 

[b6graham]

don't hold back. give your AM some damn hybrids

 

[earthquake]

don't hold back. give your AM some damn hybrids

LoL. I thought about it, but damn....that's a lot of good bullets gonna hit the Tennessee dirt, his first ever match and all.

 

[earthquake]

Reamer with short freebore.

I thought about that. Would a carbon ring do that too? Maybe I'll scrub the hell out of it tomorrow and remeasure.

 

[Mike Casselton]

It sure can.
I have a short throat 6BR and noticed a tiny bit of resistance when chambering a round. I grabbed my barrel stub and the fit was just like it was supposed to be including OAL.
I gave the barrel a quick scrub and the issue disappeared.
It's beginning to come back so this thread is a reminder for me to clean it again.

 

[earthquake]

No change in CBTO after a good scrubbing. I picked a seating depth, five different charge weights from 28.2 - 29.3 and this was the best 5-shot group.

28.5-gr H4895, Hornady 105 bthp,
2,767 ave fps
SD = 6
ES = 16

Taking them to 700+ tomorrow to see how they fly, but I don't wanna blow through more powder and bullets figuring this out. I think it'll do....for a first timer.