I'm having Pac-Nor install a new barrel (30-06) on my Remington long action. My problem is how long to make the chamber. I will be using Barnes xxx 168 grain and Nosler 165 grain bullets. I want to send them a dummy case but I don't know how long to make it. My powder of choice is IMR-4350. I don't want the bullets to take up too much space in the brass cases. With Nosler bullets I have found success with .010 off the lands. With Barnes .030-.050 is best. So I need an aprox A.O.L.

I assume you are talking about the length of the throat. If I want it set up for a specific bullet I seat the bullet in the case out as far out as I can and stay within the magazine limits and still have at least 1 bullet diameter in the case. Then tell your smith you want a specific distance off the lands from there. I doubt the two bullets you listed will give you the same setting so you might have to compromise a little.

Seat the longest/heaviest bullet you are going to use even with the base of the neck. Or check your manuals and find the longest recommended OAL. I used the OAL method when I ordered my last reamer from KIFF. It turned out perfect. I believe you want 140% of your bullet purchase for a new chamber. Meaning you would want .431 of a .308 bullet in the neck for OAL of the loaded round and be able to touch the lands. Someone else will chime in on this. Rems can take alot longer OAL than the books say, if you are not using the magazine version.

By using the 140% of the diam. (.308 x 140%=0.431)It seems that a large portion of the bullet will be in the case. Using your cal. the O.A.L. would be 3.229. Even S.A.A.M.I. specs state a 3.340 to be max.
Am I making to much of this??

You should/recomended to have at least a caliber purchase in the neck. This keeps your ammo straight and gives consistant release. Neck length on a 30-06 is .385. I would set a Barnes with .330 in the neck and have him cut the throat so it is touching the lands. That will give you .055 to seat in deeper with out passing into the powder column. Nolser and Barnes have different profiles. Make a dummy with the Barnes and seat a Nosler with out touching the die and see where you are at. Good luck I just went through this with my 280AI and I am waiting to get a Wildcat on a 222 case I ordered the other day, same thing with seating depth and throat length questions. You should be fine Chris is top notch.

The 3.34 length is the standard. So any factory ammo you buy will not be longer than that. They will also consider the shape of their bullet to insure that the bullet will not contact the lands.

If you are going to reload your own ammo then you are not limited to the 3.34. As long as your COL is longer then the standard you could still use factory ammo you will just have longer freebore like a Weatherby. If you go shorter than 3.34 then you need to check factory ammo to insure it doesn't contact the lands. I feel that 140% of dia is overkill. In the case of the 06 for example the neck is only .385" long while 140% is .4312". So that means .0462" is not even supported by the neck. It just takes up available powder area. I think 100% of dia is plenty the 300Wmag only has 87% while many would call that short I have never had a problem.

In a sense, I think you are making too much of it. In your case you have two things going for you which makes the job very easy. You have an action with a nice long box so your length is not limited by this. You have a cartridge with a nice long neck which gives you a lot of latitude in seating depth.
Keep in mind, despite your avowed intent to use one of two bullets, you may want to use others. Happily, the combination of long box and neck will probably allow you to do so.
In my experience, a throat which allows a bit of jump is not necessarily detrimental to accuracy providing the throat diameter is not too big (30s should be .3085IMO). Ultimately chamber concentricity is much more important than chamber dimensions. Regards, Bill.