I went from a 30 06 to a 270wsm case. The magazine follower did not allow the new case to feed properly. In fact the magazine would jump and scramble the live rounds. It also needed a mag ramp in place. Now it works correctly.
M700 bolt face can be enlarged to your size with a Sako extractor. Mine works exactly as intended. but the rails are another story along with the follower. The point is be sure of the expenses that you can incur incrementally they add up. You might just be getting a rifle already built but needing tweeking with a pillar/glass bedding, timmey trigger, truing the bolt. Depends on what your want to spend.
Here is an Idea of what the PTG looks like in 338 Norma. Comes with the extractor installed. As for prints of the cartridge I dont have any but depending on what you are lookinng for it's a shortened Lapua with minimum body taper set up to run a 300 smk with an OAL of 3.602 Mine runs 12 off at 3.592.
"Fast is fine accurate is final"
I just read that your building a 338 Norma Mag. Also as you stated this is based off of the 416 Rigby case. Here is where it's nice to have all the facts first. In your case now, I would not advocate using a sako extractor let alone even a Remington action. The bolt diameter is too small for this large of a case head. I would recommend you look into getting a complete custom action such as the Stiller TAC 338 that has the .750" diameter bolt and is designed for these larger cases.
You know I've been sitting here typing for an hour my response about the safety issue of a sako extractor, and how I've never had one failure in over over 20 years. But then it finally dawned on me, I've got better **** to do than argue over a sako extractor. I've got 6 Remington bolts being fitted with sako extractors right now in the shop to do.
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