Ultra mag action

mt boy

mt boy

New member
Have a 7 rum. That I don’t ever use. Was thinking of rebarreling it to a 7rem mag or possibly a 300win or 7lrm. Is this possible with a ultra mag action . Will there be any feeding issues or anything else to worry about thanks
 
It should feed just fine I'd imagine.

If it were me, I would do a fast twist 7 SAUM on that action and sling heavy, high BC bullets.
 
If you're looking for 7mm suggestions maybe take a look at the 7mm Blaser Mag. It's a beltless case and has a tiny bit more case capacity than does the Rem 7mm mag. Brass is made by Norma and readily available. Some factory ammo is available but not much so if you don't reload, it may not be a good choice.

I have one built on a Rem 700 and it shoots the 180 Bergers very well.
 
I think your better off selling or trading the rifle and starting over with a shorter action. The RUM actions are extremely long. I have a 300 and 375 RUM. I believe the 338 lapu action is a hair longer. Your going to have a huge bolt throw even if you cobbled it to feed and function with a cartridge a third to half the length of what it was designed for not not mention the extra weight not needed. Just my opinion.

I’m sure you could rebarrel it to one of the nosler magnums since I believe they use the same 404 Jeffery’s case. The 26 nosler or similar would be interesting...and just hard to come by for casings.
 
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Right I really though hard about a 28 nosler but don’t want to deal with the high dollar brass and it will just be hunting whitetails.
 
If you wanted to convert it to detachable box magazine might give you a few options. It seems to me like the ultramag case was a little bigger than standard belted magnums at the case head. I would think that a 7WSM would be a great option on that platform. Using that cartridge in short action forces you to seat deep into the powder capacity.
 
It's just one of those guns that "you" and "I" had to have and now that the new shoes wore off its not that fun to shoot with excessive recoil as the smaller calibers. I have KDF brakes on mine. The 300 Kicks like a 243 and you will make your ears bleed WO ear protection, I can tell you first hand it's true. The 375 will still purple your shoulder with the brake so it's loud and recoils yet. After three shots...or two the barrel heats up and accuracy goes down the toilet. That's why I have a lot of guns and let my RUMs collect dust in the safe. I used the 300 RUM for black bear hunting twice and shot an eight pointer with it....I've had the gun for 18 years and never shoot it. The 375 RUM I shoot two deer with...and a rabbit with a 260 gr ballistic tip. Overkill on both. I won't get rid of them because some say I'll use them again and have plenty of brass laying around for both. I'd tell you to go trade it in if you really want to get rid of the rifle because the RUMs are and have not been that desirable of caliber in the last decade and nobody wants them it seems. The current generation of shooters want video game rifles with low to no recoil to spray bullets everywhere...22lr,223,300BO,ect. Bullets you can go buy for a $1 a dozen...exagerating...but you get my point. IMO the new gen of video game shooters want rifles they can actually shoot and afford to shoot...and not look at. The long range guns with heavy recoil and that you can fry an egg on the barrel after a dozen rounds lost their popularity about three years after the RUMs were introduced. I would guess the noslers are not doing good sales wise and you won't see them in production in a few years as well. Once they faze them out in a few more years your and my odd balls will bring a premium by someone who will be dieing to own that caliber that no body currently would give you their lunch money for.

Otherwise the Nosler is basically the same as the "rebranded"...remarketed RUMs with the nosler branding with a few smaller bullet diameter choices...nothing different than what you have now and will recoil about the same.

If you really don't like the rifle trade it and move on because the short action calibers you want to chamber your RUM in IMO aren't going to work...or work well. Just cut your loss and move on. I had a couple of friends who had to sell their 300 RUMs a few years back and went through the same thing. No one wanted a rifle that costs &60/$80 per box of 20 ammo. They gave me all their brass and both bought 243 for deer hunting after they sold them. I think the recoil wrecked them.lol. I'm a big guy and not recoil sensitive but that 375 RUM when wearing a t shirt will do you in...26 rounds to be exact. I had broken blood vessels up and down my arm and chest. I have not shed a tear since I was five and it almost happened that day.

You could always neck it down to 6mm, 22, or 17 and really melt the barrel at 15,000 fps.lol

 
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I forgot I shot an antelope with my 300 RUM at a hair over a 1000 yards using a 125 grain ballistic tip loaded around 3950 fps. I took another at 250 yards with the same load...I could have clapped in the hole it left. The 1K shot antelope tilted about three seconds after I shot and ran in a 30 yard circle and collapsed. I hit it perfectly behind the shoulder broadside and poked a bullet sized hole through both lungs....I got lucky.

The other battle is finding a bullet that will be tough enough, but not too tough to expand for Kenetic energy transfer instead of blowing up like a varmint bullet. I shot a deer with a 180 gr ballistic tip and saw a small black bear harvested with the same. Nastiest gut jobs I've ever witnessed. It was like a waterfall of blood in both and the the organs were mush. Sciroccos work good along with partitions. The problem with partitions is they are not the most accurate bullets along with the crummy accubonds which defeats the purpose of a long range gun,
 
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What is next after "Ultra mag"? Well, the gun still goes bang and nothing changed.
Things changed a lot in the 50's and 60's but now it is just names that change.
Now Weatherby was my hero of all times. I never owned one but he sure had good ideas.
I guess, I will go down in history with my two favorites, the 220 swift and the 22 short.
 
Originally Posted By: willy1947

What is next after "Ultra mag"? Well, the gun still goes bang and nothing changed.
Things changed a lot in the 50's and 60's but now it is just names that change.
Now Weatherby was my hero of all times. I never owned one but he sure had good ideas.
I guess, I will go down in history with my two favorites, the 220 swift and the 22 short.




The Lapua came next...basically a 338 RUM and then the Nosler magnums. All the the same just better marketing.
 


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