Winchester conversion

[WHITEY338]

I have an older push feed Winchester Model 70 Super Express in 375 H&H. The gun was availible in 375, 416 rigby, and 458.
Question 1: Is it plausible to build a switch barrel between the 375 and a 338 lapua? Like interrupted threads or would the recoil be too much for a system like that. Also couldn't I just unscrew the barrel, buy a new bolt(with the correct head diameter, some headspace guages and screw my own barrel on?(the lapua is based on the rigby basic brass and is just a pinch shorter than the 375)
Question 2: Is it a DIY proposition? I have access to a impressive machine shop where I could do anything I needed.

 

[Jim Watson]

1. You could change the barrel and bolt but getting two cartridges of such different size and shape to feed out of the same magazine would be difficult to impossible.

2. If you have to ask, the answer is probably no. There are gunsmith tools and techniques you need on top of general machine shop equipment and practice. Of course there is no reason you shouldn't study up on it and learn on your own guns.

 

[Chawbaccer]

Have you ever unscrewed a barrel?

 

[BluesBear]

That is certainly not a job to be undertaken for Gunsmithing 101 no matter how skilled you are in the machine shop.

I can however put you in touch with a gentleman up here in the Seattle area who can do it and has done it. In fact I was looking at one of his rechamberings today. Beautiful workmanship.