Spike Camp

7 mm on 300 weatherby

7 mm on 300 weatherby
« on: February 08, 2018, 06:01:44 PM »
am thinking of a rebarrel job to this.got some brass and a doner rifle in 700 reminton magum now in 300 Winchester.any thoughts on this and what are you loadind in one if you have one?
gary b

Re: 7 mm on 300 weatherby
« Reply #1 on: February 08, 2018, 07:11:43 PM »
What would be the largest animal you might hunt with this rifle? I have both calibers, so this is an important question.
JK

eford

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Re: 7 mm on 300 weatherby
« Reply #2 on: February 08, 2018, 10:08:30 PM »
I think I real advantage of the fastest moving 7mm bullets is you can get the heavy-for-caliber bullets moving at the same speeds or faster than 180gn bullet from a .30 cal rifle. Sectional density discussions aside, the great BC offered by the 160-175gn .284 caliber bullets is among the highest for hunting bullets. At the long ranges, the BC matters more than the simple weight of the bullet.

Now I get to contradict my previous statement since my son's 7mm Rem Mag loves the 154gn Hornady SST bullets pushed at a near maximum powder charge. I have a long line of bullet styles and weights waiting for my 7mm Weatherby Magnum.
Of all the gin joints in all the towns in all the world, she walks into mine.

Every man needs to know his limits.

Re: 7 mm on 300 weatherby
« Reply #3 on: February 09, 2018, 04:34:22 AM »
Are you talking about a 7mm-300 in other words a 300 necked down to 7mm?

Marishka

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Re: 7 mm on 300 weatherby
« Reply #4 on: February 09, 2018, 05:47:52 AM »
Like Wyominghunter said, it depends on the size animal you are hunting. I have both. I dropped a young 1000+ lb bison at 125 yds using the 7mm Wby. The 300 Wby has a very wide range and it can handle bullets up to 250 grains. I like it for bears unless for coastal browns when the guide requires something larger. And, same take bears with the 7mm Wby. Alaska only requires a 30-06.

Re: 7 mm on 300 weatherby
« Reply #5 on: February 09, 2018, 06:32:15 AM »
Are you talking about a 7mm-300 in other words a 300 necked down to 7mm?

That's how I read it too. If so, you're essentially reproducing a 7mm STW. The STW is an 8mm Rem Mag case necked down to 7mm. The 8mm Rem Mag is approximately the same length as the 300 Wby (2.85" or thereabouts). So the only real difference between a 7mm STW and a 7mm-300 Wby would be the venturi shoulder on the Wby.

And after all that, you still wouldn't be able to best the 7mm RUM, which is a slightly fatter case.

I do love 7mms. Maybe think about a 7mm-378 Wby? If you want to be the biggest baddest kid on the block. :)
JW

eford

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Re: 7 mm on 300 weatherby
« Reply #6 on: February 09, 2018, 09:18:00 AM »
A 7mm-378Wby would be the screaming out of the muzzle as the fastest 7mm cartridge. There is little difference between a 7mm Weatherby and a 7 STW, but from the 378 case things would be much different.
Of all the gin joints in all the towns in all the world, she walks into mine.

Every man needs to know his limits.

Re: 7 mm on 300 weatherby
« Reply #7 on: February 09, 2018, 09:27:51 AM »
I have no personal experience with this, but here is a link from Nosler forum in 2012 that might give you a starting point. https://forum.nosler.com/viewtopic.php?f=4&t=20568

Re: 7 mm on 300 weatherby
« Reply #8 on: February 09, 2018, 09:40:28 AM »
A 7mm-378Wby would be the screaming out of the muzzle as the fastest 7mm cartridge. There is little difference between a 7mm Weatherby and a 7 STW, but from the 378 case things would be much different.
Been there done that. I had a mark v 7mm weatherby  converted to 7mm-300wby and the gunsmith screwed up the chamber. so i had him rechamber to 7mm-378wby. The 7mm-378wby would not extract a fired case no matter how hot of a load or how mild. I know it was not the fault of the cartridge but the incompetiant gunsmith. I did some velocity tests with a chronograph and was just barley above 7mmwby velocities. Roy knew what he was doing when he designed these cartridges. Maybe if the work was done by a gunsmith thatknows what he is doing my results would be better.
Good Hunting And Shooting To all
Derrill

Re: 7 mm on 300 weatherby
« Reply #9 on: February 09, 2018, 10:49:46 AM »
My son has a 7mm RUM and I have a 7mm Wea mag. The Rum gets about 75-100 ft/sec over the 7mm Wea with equal barrel length, but at the expense of appx 20 % more powder and the throat erosion and recoil that comes with that. I feel the 7mm bore can handle only so much of today's powder and the 7mm Wea is just about right. I can get 3157 ft/sec with the 175 Hornady which is right there with the 7mm STW. I think the gain of a 7mm/378 over the 7mm Wea would be very slight but the down side ( throat erosion) would be very real. JMO

Re: 7 mm on 300 weatherby
« Reply #10 on: February 09, 2018, 01:14:49 PM »
My son has a 7mm RUM and I have a 7mm Wea mag. The Rum gets about 75-100 ft/sec over the 7mm Wea with equal barrel length, but at the expense of appx 20 % more powder and the throat erosion and recoil that comes with that. I feel the 7mm bore can handle only so much of today's powder and the 7mm Wea is just about right. I can get 3157 ft/sec with the 175 Hornady which is right there with the 7mm STW. I think the gain of a 7mm/378 over the 7mm Wea would be very slight but the down side ( throat erosion) would be very real. JMO

I found the same thing, when I had a 7mm RUM and 7mm STW. With equal barrel lengths, I saw only a little fps gain, over the 7mm Wby, but burning quite abit more powder. I dealt them off, for something else, and just keep my 7mm Rem and 7mm Wby's around.  8)

Rob
cfp-223REM
accumark-223Rem
ultralite-240 Wby
synthetic-240 Wby
synthetic-257 Wby
ultralite-270 Wby
fibermark-270 Wby
accumark-270 Wby
accumark-7mm Wby
stainless-300 Wby
fibermark-300Wby
accumark-30378 Wby
fibermark-340 Wby
accumark-338378 Wby
custom-375 Wby
DGR-378 Wby
DGR-416 Wby
custom DGR-460 Wby

Re: 7 mm on 300 weatherby
« Reply #11 on: February 09, 2018, 02:13:23 PM »
I have a hunch we may see a new 7mm of sorts coming from Weatherby in the future.
I agree with the current 7mm being a great Cartridge and not needing replacement, however with Adam confirming that Weatherby is working on a few new cartridges, the 7mm is about the only popular caliber Weatherby can’t claim “top dog” status and has me wondering if that’ll be one of the new releases?

Personally, I have my fingers crossed for a Varmint round, 20-224, 220 Rocket, etc. offered in a fast twist heavy contoured 26” barrel.

Re: 7 mm on 300 weatherby
« Reply #12 on: February 09, 2018, 03:05:42 PM »
I have a hunch we may see a new 7mm of sorts coming from Weatherby in the future.
I agree with the current 7mm being a great Cartridge and not needing replacement, however with Adam confirming that Weatherby is working on a few new cartridges, the 7mm is about the only popular caliber Weatherby can’t claim “top dog” status and has me wondering if that’ll be one of the new releases?

Personally, I have my fingers crossed for a Varmint round, 20-224, 220 Rocket, etc. offered in a fast twist heavy contoured 26” barrel.
  LOL! My "varmints" are becoming more and more 2 legged!  I can't shoot them until they pose a threat or on my property.  2 doors away at a unoccupied house, no! Convincing them to trespass on my 98 year old neighbor's ( my other mother) property changes everything. Shooting "varmints" outside requires a revolver, no brass to "police" .  Consider the GSD attack as a courtesy extended to very few. 4 legged varmints( raccoons, possums and feral cats)  are handled by my 17WSM Savage, quiet, accurate and deadly. BTW, any center fire is a legal for big game here.   ;D

257 Shooter

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Re: 7 mm on 300 weatherby
« Reply #13 on: February 09, 2018, 03:15:13 PM »
Commercializing the 7mm/300 would be nice. It wouldn't outrun the 7mm Ultra but it would match the 28 Nosler. The Ultra is all but gone anyway. I have two 7mm STWs and would have to say that's about the best of the super fast 7mms.

A 7mm/300 Weatherby would mean brass would again be easily available for a cartridge that matched the STW. A 7mm/378 would be a monster but I'm not sure how advantageous it would be.

To the original post, not sure what the person was looking for.

Re: 7 mm on 300 weatherby
« Reply #14 on: February 09, 2018, 03:26:58 PM »
I hunt pa white tails.my ranges are 50 yard to out past 800 or so.i have a 300 weatherby in a 26 inch mark v rifle and the 700 300 Winchester mag.i was always impressed with the 7 mm on the 300 weatherby for years.saw it in 1968 in a article about 1000 yard shooting .
I may in the long run just get a better scope for my 300 weatherby and make do with it.
gary b