Neck/Bullet contact

[cbh560]

So I started reloading for my Rem 700 in .30-06. I am loading hunting loads with 180 Hornady BTSP for moose and 150 Hornady SST's for deer. When I checked where to seat the bullets to engage the lands, I discovered that this particular chamber has a VERY long throat. I'm talking long as in I can seat these bullets .150" beyond the normal crimp ridge in the bullet. So my question is....how much contact surface should I have between the neck and of the case and the bullet? If I seat the 180's (flat base) to engage the lands only half of the neck makes contact. If I seat the 150's to do the same, there is maybe a quarter of the neck making contact, due to the tapered base of the bullet. I would think that a .150" jump to the lands is not helping accuracy (groups are about 1 MOA, fairly typical of a hunting rifle).

 

[H4831]

They usually go by the diameter of the bullet. Most people consider half a diameter of the bullet solidly into the neck is OK. That means a 30-06 would be seated .15" solid into the neck.
Less than that is getting iffy.
However, what makes you think some jump to the lands is necessarily a bad thing? When Weatherby brought out their line of powerful magnum calibres they free bored the rifles to reduce recoil. The bullets were going like 3/8 or half inch before they hit the rifling.
I haven't heard of people complaining about the accuracy of the early Weatherbys.

 

[sunray]

Forget the 'crimp ridge' for starters. Crimping is only necessary with cartridges with heavy recoil and lever actions. Most bolt actions don't need a crimp and .30-06 rarely needs it.
I wouldn't be married to all this 'just off the lands' OAL stuff either. It's a load tweaking technique that doesn't apply to ever rifle. Especially for a hunting rifle. The max OAL with the bullet given in your manual will do nicely.