Howdy all, I am reloading for my first weatherby and would like to know what length to start my testing at. It will be in a 700 long action magazine box which I think is 3.6"?

I was thinking to just seat the 162 A-max .284 (one bullet diameter width) deep into the brass and see if that fits in the magazine box. Is this the right idea or is there a better way?

Thanks all!

BD in my MkV the coal using 160 grain bullets was 3.360 All I ever used 1 grain less of IMR 4831 than the Nosler Manual max. 215 primers, boringly accurate. The throat on the 700 may not have as much freebore as the Weatherby. If that's the case you may not need as much powder.

You need to find the lands with that bullet and see how that correlates to the mag box length. Like rooney said, your freebore will probably not be as long as the WBY barrel he had. Furthermore, if you are going to go into it blind I'd suggest going with the book (hornady manual) suggested OAL. That is, if you don't want to take the time to find the lands on your own.

thank you both rooney and bsa I had not thought of the remington throating being different than the weatherby's. I will check the distance to lands with the 162 and check back in tomorrow. Thanks again

With WBY Mags I seat the bullet to have the base of the bullet even with the neck shoulder junction. Since you normally can't reach the lands in a Wby Mag chamber, WBY OR Rem, this has worked for me in a number of them.Rick.

The throats just as long in Remington as Weatherby rifles, since the 7mm Wby. was standardized by SAAMI a number of years ago.

SAAMI (the Sporting Arms and Ammunition Manufacturers Institute) was formed in the 1920's to standardize cartridges and the interior dimensions of firearms (such as chamber throats) primarily to prevent problems with ammo made by different manufacturers. If Remington 7mm Wby. rifles used shorter throats, Weatherby ammo would create VERY high pressures.

Thank you both for that info.

Mr B. could you please let me know at what specific length (COAL) or method you would start load development if you had to load this cartridge?

I would just load the bullets out as far as they'll go while still functioning reliably through the magazine, and staying firmly in the neck of the case. The classic recommendation for how much bullet shank should be in the neck is one caliber, in this case about .28 inch, but I've found that much isn't necessarily needed.

What Mule Deer said above...Check to see what the magazine length is and start close to there. When I load 175 Nosler Partitions for my Weatherby Mk V, they're at 3.370" OA. I'm not sure how far off the lands that is but it works through the magazine w/o problems.