Ok I need help. I have a stainless Portugal M70 in 338WM. I want to rebarrel it to 458 21-22”. Any thoughts on contour? NECG sights.
Hey, smallfry, based on your reply to my .4** thread from last year, I know that you've had 458 WM's before. Unlike you, I was a newbie so based on the suggestions of Sir Ron & Sir Bob, I opted for a 23" 1:14 McGowen #5 for my first attempt at a Ruger MkII rebarrel. It's in production right now & based on emails I exchanged with their manager yesterday, I have my fingers crossed that I'll have it in hand soon. So unfortunately I can't give any experience-based feedback at the moment. But this thread is a great resource for ideas & the #5 contour often comes up as suggestion that's not too light or too heavy.
I've been reading this thread a lot since it's basically an encyclopedia of all things 458 WM. I had noticed back in 2021, you had toyed with the idea of rebarreling this rifle before. It's nice to see someone else who mulls over ideas for a long time before actually making a decision . Sir Ron's advice back then is probably still a good option:
Originally Posted by Riflecrank
Welcome to the Square Table. No. 4 Sporter is lightest, and length no more than 23", but 22" would be optimum with such a light contour, considering wall thickness at muzzle.. No. 5 Sporter is best, 24" to 25". No. 6 Sporter contour would be the heavy weight. I used to wonder about fluting a No. ^6 but that would probably be silly, and interfere with barrel-sights. 1:14" twist is optimum, but 1:10" to 1:20" may be considered for special purposes ... nah.
As someone who like quantifiable data & the ability to weigh lots of options, I've always thought this thread would be a great candidate for an indexed & bookmarked document of lots of random facts & observations. Below are a bunch of contour posts from this thread:
Of course you could always forego all of that research and hit the easy button:
Originally Posted by jwp475
Why not have JES Rebore the current barrel and shorten it
What is the diameter of the 338 barrel at the 21" mark? If you subtract .458 from that, how thick will the remaining walls be?
On a somewhat unrelated side note, a couple of days ago, a BassPro store up in South Dakota listed a LH Winchester M70 Classic Sporter in .338 WM for $599. It looked great & there was a mad scramble by the southpaws in the LH forum to grab it. I wasn't fast enough but another member was. My opinion was they forgot to put a "$1," in front of that price. I didn't need a .338WM. But anyone who puts up a LH M70 for $599, I'm going to buy it & figure out what to do with it later.
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