300 Win Mag to 300 H&H

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mistahmojoryan

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I read in another thread that rechambering a 300WM to 300 H&H is not possible without setting the barrel back about 2"....assuming there's enough steel over the new chamber to do so.

Questions: 1) Assuming it's doable, is it even worth it cost-wise or is a new barrel a better/far better option?

2) Assuming ~2" need to be taken off the barrel, does "customizing" a 22.75" barrel 300 H&H even make sense or should I be looking at 24" and up?

Just thinking ;) ....thanks for any feedback!
 
Not possible without setting back. The 300 H + H has a lot of taper to the case. I have had a 30-06 re-chambered to this cartridge and once all the adjustments for the longer cartridge were done it is an excellent shooter and feeds/ejects flawlwssly. Was done on an M-70 Classic action. If I was doing it I would want at least a 24" barrel.

FWIW, 44Bore
 
The 300 H & H Mag. chamber is 2.850" in length and the neck diameter is .338"

The 300 Win. Mag. chamber is 2.620" in length and the neck diameter is .339".

That is a difference of .23 inches.

Assuming the throat in the H & H is not excessively long or worn, and the present chamber is within correct specifications the barrel would only need to be set back about 1/4 inch.... that's if all goes well. It could also be made into a 300 Weatherby and would only need to be set back one thread... but I would not recommend the Weatherby unless you had more barrel length. It would work okay with the Win Mag I am sure...
 
The shoulder diameter is more important:

The 300 H & H Mag. Shoulder diameter is .457"

The 300 Win. Mag. Shoulder diameter is .475".
 
Yeah, I figured it was the strong taper to the shoulder that was the main issue and reason for setting back the barrel nearly 2".

At any rate, assuming it's possible, for cutting, reaming, threading, etc... about how much would it cost?
 
Its going to cost the same to rechamber the old barrel as it would to chamber and thread a new one. If the old one has sights factor in more $ to get them lined up perfectly.
 
I misread the original post...:redface:

I didn't think anyone would want to go backwards from a 300 Win Mag...;)
 
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Nothing wrong w/ the 300WM....just thinking "out loud". I'm always thinking about changing this rifle into something else. It's served me well for 10 years though so I should probably just shut up and keep hunting w/ it but the Sako V action will hold a 375 H&H so.... ;)
 
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