I'm searching for used Remington 700 long/magnum action for my new project, it will be a 338 Tomahawk. (The brass is .404 Jeffery)
If the bolt head has .532, can the gunsmith expand it to .404? or it is better off replacing the bolt head to .404?
404 bolt face is vey close to 300 HH mag face family ( the most popular bolt face in Mag case ) so open 300 HH bolt face family to 404 family ( 300 ULTR Aand other base on ) required no steel cutting to just a most amount , generaly I do that when I square the bolt face ( very important to get a perfect square bolt face )
a put a ZEDIKER/TUBBS Sako clone extractor , Rem ext is not a mecanical dream
If you want to make more cosmetic works start with a 30.06 bolt face by this way you can cut more steel and get some time look nice .
just make a little mistake by answering without reading all your post
404 is full rim dia
300 ULTRA is a rebatted rim
so you need to open the bolt face of you std mag action but the fact to install a SAKO extractor stay a good way to solve the rem extractor problem
actually except to want to use the very costly RWS brass and more esay to find , that more easy ( case avaibility ) and less costly ( REM brass and perhaps other soon ) to use wilcat base on 300 ULTRA brass
I think that a Sako extractor well fit on a 404 bolt face can extract both 404 and 300 ULTRA CASE without any change .
No UltraMag based on a rebated 404 Jeff case. It has the same diam as a 300 win mag, 7 rem mag etc. It's just a matter of rebarrelling or rechambering and having the rails opened (if a repeater) so it can feed. This is the route I would go. Remington made the diam the same as any other magnum to save from retooling and redesigning the 700.
If you go with a 338/404 Jeff Imp, you will have to buy 404 brass and have the work done to the bolt,and go with Bell brass (I'm not sure who else makes it).
Hope this helps.
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