Load development seating depth starting point

[smithjasona1978]

I am just beginning load development for a Weatherby vanguard series 2, 300 wby mag. It has .361 inch of freebore. I am using 208 grain ELD-M bullets. And my question is what my starting seating depth should be? I am gonna single load. Mag box is way too short. But with the Weatherby free bore I can chamber a round and close the bolt all the way out to 3.901 inches. Or seat it all the way in to spec at 3.560. Thats .341 inch I have to play with. Any suggestions on where to start??

 

[Dosh]

1978, you need a minimum of .308 seated in the neck or bad things will happen. The freebore is way too long to seat anywhere near the lands. Some seat to mag length and go shorter. Perhaps try seating to book spec and seat in .005 increments after may also work. Be safe

 

[smithjasona1978]

Even at 3.900 the boat tail is past the end of the neck.
Im thinking I may start in about the middle. Half way between spec and jammed in the lands. 3.750???

 

[Rich Coyle]

Start anywhere and work up to pressure. Then play with overall length. One of mine like .180" from lands. Never can tell what the rifle will like. Weatherbys can be amazingly accurate.

 

[rcoody]

Weatherby's were designed to jump. That long.freebore was there for a reason.

I would start mag length and work shorter. Try the COAL in the reloading.manual. Read about the cartridge and what Roy Weatherby says.

 

[gohring3006]

I single load the 225 ELD M in my 300 Weatherby Vanguard.
One thing you need to ask yourself is, do you mind using the bolt release to eject a round. That will dictate how far out you want to seat.

 

[dsculley]

With a secant ogive bullet, I usually run the Berger seating depth test prior to load development rather than pick an arbitrary seating depth. Since seating depth on these bullets can greatly affect group size, starting load development with a proven seating depth can help avoid frustration as you develop your load. If you happen to select a "bad" seating depth, you are not likely to find a "good" group during load development.

 

[Mikecr]

+1 dsculley
TEST for best CBTO, to begin, and continue from there.

 

[Gord0]

With a secant ogive bullet, I usually run the Berger seating depth test prior to load development rather than pick an arbitrary seating depth. Since seating depth on these bullets can greatly affect group size, starting load development with a proven seating depth can help avoid frustration as you develop your load. If you happen to select a "bad" seating depth, you are not likely to find a "good" group during load development.

+2. It'll save you a bunch of headache and $

 

[rcoody]

With a secant ogive bullet, I usually run the Berger seating depth test prior to load development rather than pick an arbitrary seating depth. Since seating depth on these bullets can greatly affect group size, starting load development with a proven seating depth can help avoid frustration as you develop your load. If you happen to select a "bad" seating depth, you are not likely to find a "good" group during load development.

Well i can attest to the validity of.the berger jump test. Worked.for months trying to get a mag length load for the berger hunting VLD. Read about the jump test and.tried it. Found my jump 0.127 off the lands. Who would of thought. An accuracy node 0.030 wide where groups go from over an inch either side to less than a half inch in the node.

That said i have found the berger hybrid hunting much like a MK. Very tolerant to seating depth.

Any vld type bullet would benefit from the berger jump test