I have a couple year old Winchester model 70 sporter in .300 Winchester magnum that I'd like to rechamber to .300 Weatherby. I'm wondering how much work is involved to do this?

Besides the rechamber, remove spacer in magazine or just just replace the magazine box and a new bolt stop what else needs to be done?

Does the ejection port need opening up also? I've read here on AR a few who say no. I've tried ejecting a .300 Wby round from and it works fine. What say you gunsmithing experts on this project.

I have to ask what are you hoping to gain ?? When loaded for a std length action of 3.3 or 3.4 inches bullets are seated quite deep in the 300 Win but it only gives up 100 to 150 fps to the Wby. If you have a longer action like the Win or Rem 700 that will accept cartridges of about 3.6 inches you can seat the bullets out in the 300 Win case and regain some powder capacity . Velocity difference between the two is much less when you use all the capacity of the Win case. Biggest difference will be doubling the price of brass and ammo when you move to the 300 Wby.

You can get away without opening up the ejection port, but opening it up will make it easier to load.

Hmmm..if is a pre 64in 300 WM, you have a keeper...The Wby version is longer and to function proper, would have to have a lot of work. New mag box, follower and action opening..and in the process....lose value

you gain ~7 yards, MPBR, making the change, and will spend a good deal to get there

quote:

Originally posted by Duane Wiebe (CG&R):
Hmmm..if is a pre 64in 300 WM, you have a keeper...The Wby version is longer and to function proper, would have to have a lot of work. New mag box, follower and action opening..and in the process....lose value

It's a classic that I bought 2-3 years back new.

quote:

Originally posted by snowman:
I have to ask what are you hoping to gain ?? When loaded for a std length action of 3.3 or 3.4 inches bullets are seated quite deep in the 300 Win but it only gives up 100 to 150 fps to the Wby. If you have a longer action like the Win or Rem 700 that will accept cartridges of about 3.6 inches you can seat the bullets out in the 300 Win case and regain some powder capacity . Velocity difference between the two is much less when you use all the capacity of the Win case. Biggest difference will be doubling the price of brass and ammo when you move to the 300 Wby.

I figured someone would ask.

Of the .300's the Weatherby version has been my favorite for a long time so I'm pretty well invested into it. Besides I like the way it handles heavy bullets compared to the Winchester version and no brass isnt more expensive for it.

quote:

Originally posted by Cougarz:

I've tried ejecting a .300 Wby round from and it works fine. What say you gunsmithing experts on this project.

Don't forget with shorter 375 bolt stop the bolt (and hence the live round) will be further back in the action.

As to 300 Win and Wby and in 26" barrels I have had quite a few over the years. In "accuracy" rifles when both loaded just below where accuracy falls off the difference 180 grainers is from 100 f/s to 130 f/s.

I guess this is a mental thing but for me a 300 Magnum is 180 grain at 3100 f/s "plus" The 300 Wby does that with ease even with the wrong powders. Also something bout the 3000 f/s and 200 grainers and the 300 Wby is 3050 to 3070 but 2950 sees out the 300 Winchester.

If you are someone who finds the 300 Winchester at your upper limit for recoil/blast then the increase with the 300 Wby will be very noticeable.

Coat of brass was mentioned. If load the 300 Wby back to equal top loads in the 300 Winchester then brass life in the 300 Wby will be just this side of forever.

I put the 300 Wby and 375 H&H together. Both have lots of pizzazz and will do job on anything while giving up very little in the way of practicality. However, I always feel a 375 belongs in a M70 and a 300 Wby a Mark V but that is all just personal stuff.

Buy this and you will be money ahead all the way around.
https://www.gunbroker.com/item/851920467

quote:

Originally posted by Cougarz:

quote:

Originally posted by Duane Wiebe (CG&R):
Hmmm..if is a pre 64in 300 WM, you have a keeper...The Wby version is longer and to function proper, would have to have a lot of work. New mag box, follower and action opening..and in the process....lose value

It's a classic that I bought 2-3 years back new.

OK..so it's NOT a pre 64...forget all I said. In my opinion you can't hurt the value no matter what you do

A 300 Winchester Pre 64 would not be real common since the 300 Winchester was introduced in 1963.

Thank you all for your responses.