.300 Weatherby vs .300 Ultra Mag

B

bayou

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Any thoughts? The platform is not an issue, I just want opinions on the cartidges. A friend of mine is ready to sell his rifle in .300 Weatherby. I think I'll be able to get it for under four hundred. The cartidges seem very similar performance wise, with the edge given slightly to the Weatherby. Any gripes?
 
actually the ultra will have the slight edge if your reloading as it hold more powder according to hodgdon it will burn 10 to 20 grains more powder for 100 to 200 fps.
 
run a 220gr pill out of both and you will see why the RUM was developed. It is NOT for widdle bullets like the 165's and 180's,..it is a monster that pushes BIG LONG bullets at a speed not acheivable by it's factory competitors.

Weatherby brass and ammo is wayyyyyyy overpriced because of a lingering fad. They use great brass,..but the markup is rediculous. Nosler now makes RUM brass,..so the brass issue is becoming a mute point.

I'll take the RUM,...no belt and more power.
 
Don't know where your getting the edge goes to the Weatherby. If your talking about the 300/378 then yes, but the Ultra-mag I chronographed gets 3380 fps from a 180 grain bullet where the 300 Weatherby another friend shoots is getting 3200 fps.

Like JustC said the Ultra-mag brass is much less expensive. The only 300 mag I would consider today is the Ultra-mag if your looking for flat trajectory. My favorite mag rifle has always been the 8mm Rem mag pushing a 220 grain Sierra boattail at 3080 fps and I've often thought of boring that out to an Ultra-mag case for 3200 fps from that same bullet.
 
justc, have you tried nosler brass? what I have used of it, won't hold up nearly as well as rem. and not even as consistant in neck thickness, my lot of 270 cases varried as much as .006, and have a report from a smith who evaluated some nosler rum brass and neck variation was worse on it than my 270's.
I was blowing primers with fireform loads using noslers that the rem and win took in stride.
If it were me and I was gonna handload, I'd go with a 300 Allen Express, more power than either and much better cases.
RR
 
I was comparing the factory loadings of both - can't remember where, of course - and for the same bullet the company gave about 50-100 fps edge to the Weatherby.

However, you've all brought up valid points. I'm not in dire need of a long range rig right now, but had been doing a bit of research on some different cartridges that wouldn't be handload only. Then this guy started talking about selling his rifle, so I wanted to get the collective opinions of the board.

Thanks for all the info. As I've not settled on any cartridge, .338 RUM is still out there, and if I'm going to buy a new rifle, then I'll have to be deciding between the .338 and .300 RUM's, as well as a couple of others.
 
If I were planning on a lot of elk hunting or going to Alaska I'd probably go with the 338 RUM. There's certainly nothing wrong with the Weatherby at the price your talking about. A friend has one built on the Howa action and it's both accurate and packable.
 
Here's a visual comparison that may only be viewable for members, it's a public link, but I dunno if everyone can see it. The 300Wby has a case capacity of 92.4 gr. water, the RUM 108gr water. They both have a SAAMI MAP of 65kpsi. Ammoguide states the RUM was designed to outperform the .300 Weatherby Magnum, propelling a 180 grain bullet at 3300fps, with a muzzle energy of 4352 ft/lbs.


http://ammoguide.com/cgi-bin/aicompare.cgi?sn=VqCtUikAIJ&loadset=28&xxglbl=1
 
If you compare sources such as Remington's catalog and Hodgdon's reloading data, the RUM comes out with about a 125-175fps edge.

If you want the hotter gun and want to pay price of a little more recoil and muzzle blast, go with the RUM. The obvious comment is that if the Wby won't do the job, neither will the RUM. Don
 
Well, I may have to weigh the price of the gun vs the 14 grain difference in capacity. I'll definately handload for this one since the ammo is so expensive. And of course, there's the question of if the animal will get back up, saying "aw, that was just a .300 Weatherby".

The guy knows I'm interested, so he's supposed to say something when he's actually going to sell it. I've not seen the gun, but I think it's the Vanguard. The cartridge will do everything I need it to do - but then so will my .270 and my .45-70.
 
Here's my buddies 300 RUM at the Range. 180 grain factory bullets.

Dustinatriflerange.jpg


Here's what my chrono says.

Chrono300RUM180Factory.jpg


Nuff said?
 
Well IDBob, looking at the barrel profile on your friends gun, it looks rather lightweight. Certainly doesn't look like an enjoyable bench rest companion!

I'm also a little surprised that the muzzle blast didn't damage your chronograph. Don
 
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interesting, according to their propaganda, they would be far tighter in tolerances than Remington. I have some on order for the RUM and will run measurements when I finally get it (backorder). I would have thought they would have easily beat remington in the dimension dep't as remington seems to me to be the sloppiest of all mass produced brass. It is a little thicker though, which allows me to uniform the necks.

come on Lapua,..get on the RUM wagon and make some good brass. /ubbthreads/images/graemlins/confused1.gif
 
I used to have a .300 Win Mag. Great round. And yes, it's more than I really need. But then it's not about "need". As I said earlier, my .270 Win and .45-70 will handle everything I need. But I've been having a hankering for a really fast cartridge.

I kick myself to this day for getting rid of my 7 STW in a fit of madness in 1999. It was the Sendero with the laminated stock.

So, I want another fast cartridge.
 
I have both a 7mm RUM and a .338 RUM. Both are custom builds on a 700 action and Lilja #4 barrels with breaks. I can't say enough good things about them. My .338 will push a 250 Grain Barnes X bullet at just under 3000 fps. The 7mm RUM hits deer like the Hammer of Thor. 140 gr pills and there is no tracking on a whitetail deer. I did take a coyote with the 7mm in Kansas last deer season, If your looking for fur friendly, this aint it!

Steve Garrett, I suppose we could all ride mopeds too, but a Harley sure sounds nice and feels good! /ubbthreads/images/graemlins/cool.gif
 
Totch, what bullet are you shooting in the 7? The last deer I shot with the STW was using a 140 gr A-Frame that punched a 7mm hole going in and a 7mm hole going out. Gelled EVERYTHING in the chest cavity.

Man, I loved that gun. Have I mentioned I regret getting rid of it. Tempted to build one that looks just like it.
 
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