Re: 338 conversion
If it were me i would go with a PT&G bolt made up for the Lapua for several reasons , like , ordering it to fit the action tighter , smaller firing pin hole , the lugs are a little bit thicker , having the ejector located where it will work with the Sako extractor a little better and you can have their threaded handel welded on and timed to the action correctly where the factroy bolt probably is not.
I would also opt for the coned bolt face as it will allow a little better feeding and even thicker bolt lugs.
You should be able to sell your factroy bolt for $125 pretty easy especialy if its been trued up and with the Sako extractor.
But in short yes your current bolt will work for the Lapua and if the cost of the brass isin't an issue then I don't see any bennifit of going with the Edge over the Lapua especialy if your going with the Ackley improved version
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