All,
I have accumulated the parts that I would like to use. However, I may have made a miscalculation. I have a Model 70 Classic in .300 Win Mag that I would like to turn into an 8mm Remington Mag. I have the barrel and all of the other parts what I need to know is if the action and magazine are long enough for this to work properly. The action is up on the farm or I would measure it myself. Will I have to seat the bullets in to make it work or will the Win accomdate the 3.600" OAL? Thanks.

Cheers,
Jason

You will have to get a 300 Weatherby magazine box. The 300 Win Mag has a small folded block spot welded into the rear to shorten it. The Weatherby does not, so it is full length. You may have some minor feed rail work but it is a straight forward converison.

By all the parts...have you included?

a longer 300 Weatherby follower

a shorter bolt release or will have to shorten yours.

And, from a 300win, you'll need to cut away the very rear of the feed rails to let the longer cartridge come up and be picked up by the bolt, at least it was so on the Swiss-owned M70 taking up space in my gun cabinet.

This 300 weatherby box is 3.600 total inside. Naturally, I can't load that long. Say about 3.570 for good feeding.

Thought that you had to open up the rear of the action to load .375 type cases. I do know that the scope bases are different. A friend did buy the pieces listed above for his .338. Had the barrel throated to seat bullets out a little. Why I don't know.

I haven't tried it, but supposedly the full length magnums like the 8mm rem mag will function and eject fine through the M70's with the shorter ejection port cutout like your .300 win mag. As mentioned above, it will require a long magazine box without the spacer and a full length follower along with a different bolt stop and ejector.

Myself, I'd probably get a M70 in 7mm stw, 300 weatherby, .375 H&H or .416 rem mag to start with and build on that, it'll save some hassle and you'll have the long ejection port cutout which I'd want.

I believe the factory 375 has a slightly larger longer ejection port. However I have built numerous 7STWs (8mm mag case) by simply using a magnum action. Replacing the mag box and ejector with the ones for a 300 Why. I didn't have to do any work to the box and it ejected just fine. You can also just remove the spacer in the back of the mag box and shorten the ejector if you don't want to order new parts.

I just looked at both of my model 70s (375&30-06)and heres the deal. The mag box is as stated a folded piece in the rear. I am not sure about the ejector but it looks shorter. The opening in the action IS the same size (go figure). Sooo the conversion should be replace the magazine box change the ejector and new barrel. Have fun

I'd consider going to the .358 Norma Mag.

Essentially the same length as the .300 and necked-up .338 brass works fine with no feeding issues to resolve.

Gobs more bullet selection than 8mm, up to at least 300gr. (Woodleigh) Check the manuals you may find the Norma outpunches the .375 in the 300 gr weights.

Whatever you build get the twist rate right for the heavier bullets.

OK guys I had a brain fart.

The gun in question is a M 70 Classic,

The ejector will have to be replaced with a 300 Weatherby.

The bolt stop also will have to be replaced with a 300 Weatherby or shortened.

The follower may have to be replaced also, I would try it first and see how it feeds.

The ejection port on the 375's is opened to the rear to speed up the loading of the magazine of a dangerous game gun. The 8mm Mag will function without this modifcation. You have to take a little more time when loading the magazine, thats all.

Add a new barrel and you are ready to go. I hope this helps.

Thanks all. I am still wondering if it is worth it. I really would like to buold this baby but.... It will probably happen. Just have more parts to go find. Thanks and cheers, Jason

brownell's has all the parts you need.

Gabe

Jason

You can drill out the spot welds of the spacer in the magazine box and use your original box . Try out the follower you have , very likely it will work . The bolt stop and ejector can be cut back to the proper length .

So , it is quite possible you won't need any additional parts .........

[ 05-21-2003, 16:44: Message edited by: sdgunslinger ]