Anyone use a 8mm/RUM or 8mm/378 WBY

[Overkill338]

Trying to find some information on both. Wanting to build a wildcat on a Savage action. I was told this would be a great forum to find information on some big boomers.

Thanks

 

[MudRunner2005]

Why not just rebarrel it as a .338-378 Weatherby Mag.

That's a real "big boomer".

I have a 7mmSTW...which is an 8mm necked-down to a .284 caliber bullet.

It's a hot-shooter. I enjoy the hell out of it!

Why not just go with a 7mmSTW???

You can find ammo for it, you can shoot 1,000+ yards with it...and it will take down ANYTHING on the PLANET!!!


I'd suggest either a 7mmSTW.......or a .30-378 Weatherby Mag. or a .338-378 Wby. Mag.


Of the three, my top choice would be the .30-378 Wby. Mag...but ammo will cost you about $100-130 a box!!!

7mmSTW ammo will run you about $50-70 a box.

And .338-378 Wby. Mag. ammo CAN run you close to $200 a box!!!


So, I'd stick with a 7mmSTW...bad-*** round, and will do whatever you plan to use it for!

Even scare the **** out of other people at the shooting range, when you fire it!!!

However, I'd strongly recommend a muzzle-brake.

I'm no little, weak guy...by ANY means...

But...It's not the politest round on your shoulder, if you plan on shooting it all day long.......don't be a fool......get a muzzle-brake!

 

[JPRITT]

holy crap slayer! no more coffee for you. that wore me out trying to follow that post.

 

[4xforfun]

I think the biggest drawback with an 8 mm is bullet selection, or lack there of. You will be very limited on your bullet selection.

Another problem would be cost. This is a wildcat.....no factory dies. Custom dies are not cheap!!! Best case would be a bushing die with proper bushings. I did some costom loading for a 7mm-300 wby and simply used my 300 wby neck die with the proper bushings. I don't know that this would work with what you want. As far as FL sizing a wildcat with a standard die......I think you would be out of luck.

I agree with the other guys....7 stw, 30 378, 33 378, or a Lapua.

But, if ya gotta do it....let us know how it works out!!!

Good luck, and have fun!!

 

[Tyler Kemp]

8mm bullets have sucky BC's, 338 is definetly the way to go.

 

[MudRunner2005]

Like I've said before...sometimes I get a wee-bit bored @ work.

Plus I felt he needed all the facts before he gets into "big boomers".

You don't necessarily want a gun that that's so **** big, that you can't afford the ammo, to make it go BOOM!

You know?

I mean...he's a "Newb" on here, so, I don't know how far his "big boomers" knowledge extends???

Hahahaha!!!!

 

[Marine sniper]

If there were a decent bullet for the 8 mm the 8/ 378 would be a great cartridge, but there ain't so go with the 30 or 338/378.

 

[Overkill338]

I shoot my .300 Win Mag weekly, and also mess with my .325 WSM from time to time ( I load for both). Neither of which are in the same class as the big Roy cartridges. I have had some bench time with a .375 H&H, as well as Lightfield Slugs from a 3.5" 12 gauge, so recoil shy I'm not.

There is no way Id ever consider one of the .378 based cartridges without handloading. It just wouldn't be worth it, no matter how big of a smile it put on your face at the range.

 

[MudRunner2005]

I shoot my .300 Win Mag weekly, and also mess with my .325 WSM from time to time ( I load for both). Neither of which are in the same class as the big Roy cartridges. I have had some bench time with a .375 H&H, as well as Lightfield Slugs from a 3.5" 12 gauge, so recoil shy I'm not.

There is no way Id ever consider one of the .378 based cartridges without handloading. It just wouldn't be worth it, no matter how big of a smile it put on your face at the range.

I'd still recommend the 7mmSTW.

It's not a bohemoth, like a .416 Rigby...but it's a well known cartridge.

You can even buy Federal Premium ammo, pre-manufactured with 160gr. AccuBond bullets (BADD!!!!)

I'm planning on getting some of those AB's (AccuBonds) for my 7mmSTW!!!

I would seriously consider a 7mmSTW if I were in your shoes.

And YES...it does turn heads @ the firing range...people want to know what that "cannon" is used for?

 

[RockyMtnMT]

If you are going to do a wildcat, I would recommend that you base your cartridge on the 338 Lapua. Brass will take much more pressure than the other brass. Weatherby brass will not take much pressure, in fact Weatherby does not recommend reloading their brass. They consider it a one firing brass.

I agree with the prior post that the bullet selection for the .338 or .308 would be better.

If you are interested in a big overbore in a 30cal, I had a 30-338lap imp built last year. C H Tool and Die built my dies. Price was very reasonable, and now they have it on file.

One thing I would do differently next time is I will not get another tight neck. All the neck turning sucks.

I believe the Ultra mags would be a better choice than the Weatherby as well. Better, less expensive brass. I did the 30-378 and three firings on brass is not good when brass costs almost $100 per 20. If you do a Weatherby, do not push it.

This is just my opinion, and we all have one of those. So take it with all the others that are coming, shake them around and see what comes out. Good luck with your project.

Steve

 

[MudRunner2005]

If you are going to do a wildcat, I would recommend that you base your cartridge on the 338 Lapua. Brass will take much more pressure than the other brass. Weatherby brass will not take much pressure, in fact Weatherby does not recommend reloading their brass. They consider it a one firing brass.

I agree with the prior post that the bullet selection for the .338 or .308 would be better.

If you are interested in a big overbore in a 30cal, I had a 30-338lap imp built last year. C H Tool and Die built my dies. Price was very reasonable, and now they have it on file.

One thing I would do differently next time is I will not get another tight neck. All the neck turning sucks.

I believe the Ultra mags would be a better choice than the Weatherby as well. Better, less expensive brass. I did the 30-378 and three firings on brass is not good when brass costs almost $100 per 20. If you do a Weatherby, do not push it.

This is just my opinion, and we all have one of those. So take it with all the others that are coming, shake them around and see what comes out. Good luck with your project.

Steve

I agree!

Steve knows his stuff!!!

Listen to him, and he'll guide you in the right direction.

He helped me make my decision on a new caliber for this year to hunt whitetial deer with...and I have never felt more assured in my choice of caliber, DESPITE the fact that I have NEVER owned or EVEN shot one before!!!

But I know he knows what he's talking about...so I'd recommend listening to his $0.02.

 

[4xforfun]

If you are going to do a wildcat, I would recommend that you base your cartridge on the 338 Lapua. Brass will take much more pressure than the other brass. Weatherby brass will not take much pressure, in fact Weatherby does not recommend reloading their brass. They consider it a one firing brass.Steve

I think I RESPECTFULLY disagree with this statement. I do agree that Lapua brass is the best on the planet, along side RWS. But Norma brass is a close second, and FAR superior to the rem, win, fed, ect.... brass that is out there.

And as far as Weatherby/ Norma not recomending reloading their brass....imagin this.

A hotshot lawyer who loves to hunt, decides that the economy is bad, and decides to handload. Obviously Court (that is his name in our little story) shoots only the finest Weatherby Lazermark rifle. He grabs up his used weatherby brass (or buys new brass) and starts loading.

Now Court is real book smart, but as far as common sence.....not so much!!! Court looks at his shiny new reloading book (book smart, remember) and proclames.."I will shoot 79 G of RL 25 behind 180 NBT". Or what ever. He goes to the store and picks up his new stuff, but they are out of RL25. Being a man, who HATES to ask questions for fear of looking dumb, grabs a pound of RL 7 instead.


BANG...............

Now, two years later, Lefty (he changed his name because he lost his right eye and hand in the accident) sees somwhere on the internet where someone says that Weatherby/Norma does not recomend reloading their brass.


HE CHANGES HIS NAME BACK TO COURT!!!

I just don't believe that this is true.

Like I said , I RESPECTFULLY disagree with you, and I won't get in a ****ing match, or demand you proove your statement. Just not my way.
But, most of the guys I compete with use Norma if Lapua isn't available.
I use it in my 300 WBY 1K comp gun and have gotten 6x out of them so far, and see no reason why I won't get another 6. I just need to learn how to anneal the necks.

 

[Marine sniper]

I have NEVER heard Weatherby recommending not to reloading their brass, if it is true, I would agree it is because of some dirtbag attorney.

I have been reloading 300 Wby's for over 20 years. Weatherby brass is excellent brass, not as good as the Lapua, but very good.

The 300 and 30-378 have both held numerous 1000 yard world records. When the 338 Lapua does this I will give it credit. I believe both of the Weatherby's are inherently more accurate than the 338's. This could change with the better 338 bullets.

I get 5-7 reloads out of my 300 Why brass pushing 210 Berger's at 3000 fps, ES of around 15 fps and honest .25-.35 MOA for an Average at 100 yards. .5-.6 MOA for an average in field conditions (off a bipod) out to 900 yards

 

[Overkill338]

Thanks for all the replies. I looked at the 7 STW before when I had a 7mm Rem Mag, but at the time didnt see any need for two 7's. Isnt the 7 RUM a step up from the STW ?