7rum....thinking of changing...

I have shot a 284 caliber since out of high school....
Do have a 280ai in an older style Remington mountain rifle...noodle barrel and discolored bolt handle...same rifle(other than 2506) I gave to my son...and he outshoots me with it...
Was considering changing that 7rum(26") to a 7wsm(24")...could that be done just by shortening the shank? ...I would like to have a little more freebore in the 7wsm in the safe...

26Reload said:

I currently have a Remington 700 7RUM....shoots okay...but burns a lot of powder to get a 168gr bullet to 2950fps...91gr rl33....
Have a 7WSM that can easily do that....
Limited with a magnum bolt face...but curious what other options there can be to change out a barrel to a....
Don't necessarily need another magnum caliber...just thinking different cartridge.....
Also been thinking of selling it....with all the accessories for reloading...
Couple boxes worth of brass and rcbs dies....
Throw out some ideas please....

Click to expand...

There's a lot of bad info in this thread on the 7mm RUM. It's not a very easy cartridge to figure out and it does not come from the factory with the proper barrel length or twist rate.

Remington screwed this cartridge up big time.

The 7mm RUM is great cartridge, IF you know what you're doing. You just need a 30" barrel to burn all that powder.

Twist has to be faster than 1-9, but you need to seriously think about going any faster than 1-8.5. At this point you will have to build a rifle around a bullet, and the bullet may not work or still be in production by the time you get the rifle. Ask me how I know this. That's a very narrow window on twist rate.

However you will be limited to either solids or bonded bullets.

On the plus side there is an insanely flat trajectory. Some bullet and powder combinations can take bullets to 1,000 yards with less than 4.5 MILs of elevation correction.

140gr. = 3,700 - 3,800 FPS

150gr. = 3,700 FPS

160gr. = 3,600+ FPS

180gr. bullets = 3,400+ FPS

190gr. = 3,300+ FPS

The muzzle energy is equal in some cases to factory .338 Lapua.

It's not for the novice, and it runs best right at the maximum pressures. Oh yes, and a muzzle brake is mandatory.

pikeman said:

Have you tried some different powders with that bullet. H1000, retumbo, Rl26. I can get the speeds you get with the 175 eld-x and H1000 in my 7 mag.

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I also have a 7 RUM and my two loads with the heavies are =
3170 ft/sec using 94 grains of Retumbo and @ 63,000 psi (Conservative).

For the 175, (Again Staying at a conservative 63,000 PSI) My load of 91 grains of Retumbo gets 3050 ft/sec

Barrel length will have an effect on the velocity, (The 7 RUM needs 26''+ barrels to get the velocity) but with higher pressures it will add lots of velocity if the right powder is used.

H 1000 is also a good choice and the rum only needs 90 grains to reach 3100 ft/sec.

With the right combination of barrel and powder it will amaze you with velocity and accuracy. I have a 7 STW that I realy like, but when I need to push the bigger 7 mm bullets, I change to the 7 RUM.

My RUM will reach velocities well past the 150,s and 160,s jacket abilities.

Just my experience with the big RUM.

J E CUSTOM

Those gotta be bigger rifles....the rum I had was a light version...sporter barrel...even after i put in in an aluminum bedded Stocky it still liked to jump up and eat the brim of my hats.....
Shot good though....and the kid that bought it has been really impressed....
Kinda of sad I let it go.....oh well...lite weight older Remington mountain in 280ai is okay to shoot along with the 65284......
Now just to hunt........

26Reload said:

Those gotta be bigger rifles....the rum I had was a light version...sporter barrel...even after i put in in an aluminum bedded Stocky it still liked to jump up and eat the brim of my hats.....
Shot good though....and the kid that bought it has been really impressed....
Kinda of sad I let it go.....oh well...lite weight older Remington mountain in 280ai is okay to shoot along with the 65284......
Now just to hunt........

Click to expand...

This is the perfect place for a good muzzle brake !!!

I ran the recoil Test on my 7mm RUM loads in my rifle with the 168,s and with my rifle weighing 11.5 pounds, the recoil without a brake was 32.6 ft/lbs. With the brake it was 8.5 ft/lbs for 98% of the gas recoil.

With the same load, your rifle it would have 40.9 ft/lbs without a brake and with the brake on my rifle it would be reduced to 11.1 ft/lbs.

The rifle would not only be manageable, it would be fun to shoot.

Ear protection is a lot easier to get use to than recoil.

J E CUSTOM

I wear ear protection all the time..shooting or using had equipment for work....
the recoil was never the problem.....
i challenge myself to relax and hit targets....challenge myself to not flinch by pulling that trigger really slow sometimes......
But........
I would never like the noise of the brake.......my ears are bad enough...

Let me save you guys half a barrel.....

120gr.-168gr. = Retumbo

168gr.-190gr. = US 869

"Let me save you guys half a barrel....."

Well where's the fun in that......

If it takes half a barrel too get a load worked up something wrong! running this case with 140-170gr bullets is comical and really those are left up to the smaller cases( but it is fun to rip a 140 gr at jacket exploding speeds) and really when its loaded w/195 or 200gr @3100-3200 it brings out the inner monster!

I used a 7 mm rem mag for 1000 yard matches and it was great. It pushed a 168 grain Match King to 3254 ft/sec. "BUT" brass life suffered.

This velocity is child's play for the 7 RUM and accuracy and brass life is great. Loaded correctly, it out does my STW with little effort.

With careful planing and good component choices load development
can be quick and simple.

J E CUSTOM

I'd go 8-twist to shoot the heavy bullets in 7mm RUM.
Anything lighter than 175-180gr bullets is wasted child's play in this cartridge.
The efficiency to be gained in this dragon is with the heaviest bullets.

But you're not in the mood, at least not yet...

I run mine with Hammer 143 grain pills over 3,600fps , I was just trying to burn out the 9 twist barrel and get a 8T but I found the gun is a ton of fun to shoot with zero recoil and as THEOTHERDAVE said insanely flat.