Big Z

I'm wondering what your thoughts are on the 30-378 Weatherby Magnum, versus those of the 300 Remington Ultra Magnum.

I'm thinking that a few years down the road I want a rifle in one of these chamberings. As I handload, there is no real concern over availability of ammunition or components, nor does cost of brass need be part of the equation. In fact, let's ignore completely the components and get down to other characteristics of these two magnums.

Reloadability, design advantages or flaws, noticeable ballistic difference, ability to handle bullet sizes, etc.

Feel free to go off on a tangent about certain distinctions you feel set one apart from the other .

salukipv1

although I hear the .30-378wby is their best seller, by amount of ammo sold, I can't imagine it being so popular, though guys are obsessed with the biggest fastest etc...

Personally I'd never buy a .30-378, I have .340wby, and would consider owning a .300wby, but not that monster.

So of the two, .300 RUM and .30-378 my pick would be the .300 RUM.

I thought the .300RUM was more of the match of the .300wby though, but perhaps handloaders can load the RUM even hotter than the .300wby.

Either way who needs to shoot a 180gr or 200gr bullet that fast?

Are you looking at these for a specific reason? ie long long range shooting/hunting? 500yds plus?

Not that it's apples to apples, but my .340wby with 200gr bullets will at least come out the muzzle quite a bit faster than a .300wby shooting 200gr, and even faster than the .30-378 w/200grs. Of course most 30's will be shooting 180grs, and most .338's will shoot 225 or 250grs.

So my advice/choice would be just about any other 30 than the .30-378.
I really see no need for anything bigger/faster than a .300wby and/or .300RUM

Please tell us the reason you want a superfast .300 though, perhaps you can get away with something smaller and still fast, like a .270wsm or .257wby?

Perhaps a 7mm Rem.Mag. loaded with some high BC bullets can do the job down range too, ie more energy at 500-1000yds than even a .300RUM?

I think I'd be comparing .300wby to the .300RUM though, and my choice might be the .300RUM of the two.

Personally though, I just think there's something cool about a .338 mag, perhaps its that they're less popular, ie everyone and their brother has a .300mag, and claims their version is the best. So a fast .338 like the RUM or .340wby is pretty sweet, I've heard that .338RUM's kick is particularly brutal, ie fast and hard, though my .340 is not worse than my .300win.mag, and perhaps even less so and that's without a muzzlebrake! I believe you can handload that .338RUM quite a bit faster than factory loads, but again that kick may stop you from loading it that hot.

So it's just my opinion of course, but I think the .340wby is better than both the .300wby and the .30-378wby. Course the .340wby and 7mm Wby are their most normal cartridges IMO. Ie the case that pushes the .257wby ie 100gr bullets, is also the same case that pushes 175gr 7mm bullets. ie their biggest caliber for case cartridges...

it's like the .375wby vs. the .378wby, which I think they've kinda killed off their 378 on their own doing nowdays, even though the .375wby is slower than the .378, I think most would rather have and say the .375wby is the better cartridge of the two.

And while you're at it, what about the .338 Lapua?

bigbulls

RUM... no belt and non radius shoulders.

But my honest opinion is cases the size of the RUM need a .338" diameter bullet or larger and cases as large as the 378 WBY need a .358" diameter bullet or larger. Anything smaller is way too much powder being squeezed into too small a hole and things like throat erosion become excessive.

afp

Both the 300 RUM and the 30-378 eat barrels. With 26" barrels, there isn't a lot of different in velocity between the two. The RUM has the advantage of no freebore, and relatively inexpensive brass. Also, RUMs are usually cut with tighter chambers since they headsapce off the shoulder.

Now in a custom gun, you can have a 30-378 cut with a tight chamber as well, though you might have to order a custom reamer. Typcially, chambers for belted magnums are cut with a lot of room in front of the shoulder, meaning the brass will flow around .018 to .025" on the first firing. With a 300 RUM, the brass will only have to flow around .003 to .005" on the first firing, meaning RUM brass ought to last longer.

Gus tell me they can get 3200 fps with 200 grain NABs, but I could never get either of my RUMS to shoot the Accubond accurately at those speeds. I also hear rgat 180 NABs will run 3300-3400 fps form a RUM.

I shoot a lot of heavier recoiling rifles. I can shoot my 416 remmy comfortable for many rounds, and was able to get an ocassional 1/2" group out of the 338 RUM I had. To me, an 8 lbs all up 338 Winny recoils rather mildly.

Having said that, I found I didn't like how my 8.5 lb 300 RUMs recoiled. Lots of snap and twsit. The 338 RUM generated more snap and push but twisted much less. I decided that the 300 RUM just wasn't worth the 200 fps it gave over the 300 Wby/ 300 Ack.

Some guys think that these big 30s are great 1000 yd guns when chambered in heavy rifles. They aren't. The recoil too much and wear out barrels to fast. I absolutely cleaned house with a 300 WSM shooting a 220 grain SMK in 1K BR competition. the short fat 30s to the 300 Winny still seem to be the 30 cal chamberings of choice in that game.

streetglideok

I have the 300 RUM myself, and other then the brain rattling recoil, its a real blast to shoot,lol. I thought the idea behind a 30-378 would be cool, but the recoil has to be intense, not to mention the muzzleblast. From what Ive seen, brass costs more, that much more retumbo or H1000 to buy, and with the severity of the case to bore ratio, not a significant gain over the RUM. Either way, unless you're pushing the 180-200 grain bullets, IMO you arent taking advantage of the big boiler room they put in there. I just got into reloading here, and with a 7mm rem mag already, I think I'll be focusing on the 200 grain rounds for the 300, and lighter bullets for my 7mm.

Frank in the Laurel

NEITHER is needed by anyone in the lower 48 states for anything..ALL that noise, expense of cases, extra powder, wear and tear in the barrel throat, RECOIL, RECOIL AND MORE RECOIL for a couple hundred feet per second..just no need.. the same bullet placed in the same spot by a .300 wm, wsm or saum will have the same results with far less of everything you mention above. FOR the average guy there's just no need, now if you into super long range killing from 750 up to where ever your equipment will take you, OK.. but for anything up to 750 there's just no need..a good ole 300 mkg out of my .338 wm will kill anything that either will hit beyond that will less of everything also..they are specialized and useful for sure BUT not for the average Joe hunter..

Big Z

I'm not in this game to make things more dead. I'm in it for flat trajectory, a future in CASUAL long range targets, and cartridge envy . Why not have another gun? I narrowed it down to 2 that shoot flat and that I can load 30 cal bullets in. Sounds like the RUM is winning for being beltless, more popular, and brass life.

streetglideok

Exactly, why not have another gun or three, it ticks off the liberals!lol

salukipv1

since you're reloading, have you considered the 7.82(.308) Warbird by Lazzeroni?

7.82(.308)WARBIRDŽ
150* 3775 fps
180* 3550 fps
200 3350 fps

http://www.lazzeroni.com/ct_lacart.htm

Big Z

Salukipv1, Yes I have considered the Lazzeronis. However, they are going to run me double or more the cost of a high-grade weatherby or 700. The features and accuracy are outstanding, with a guaranteed sub MOA to 500yds. Perhaps I could have a 700 action used to build a lazzeroni mag. Know if that's do-able?