7mm Remington Ultra Mag

[meatyrem]

Kirby,

If you happen to see this I was wondering what you think about my post #23? I have the powder should I give it a try?

 

[Nimrodmar10]

I hate to admit defeat but I finally gave up on the Bergers. Figuring that Remington might have learned something with their factory loads, I decided to try the Swift 150 gr. Sciroccos. Having not had a lot of luck with the Retumbo, H4831sc or H1000, I tried the US-869 with the Swifts in my Sendero. Loading 104.5 gr. of US-869 with the Swift Scirocco 150 gr. to an overall length of 3.60" is giving me groups of 1/4-1/2" at 100 yards. The velocity is running at 3325 fps which is what the Remington factory loads are doing. The chronograph is showing very consistent loads with extreme spreads of 13-15 fps and a SD of 5 for 5 shot groups. These loads are for my gun and should be approached with caution.
My next step is to start stretching them out for distance and see how they compare to the drop tables.

 

[NZ Longranger]

Another bullet that works really good in factory RUM throats is the 175gn SMK. It is far more forgiving of the long factory throat. The new 180gn SMK is also as good if not better at handling a large jump. You can push either of these to 3150 to 3200fps with either Retumbo, H50BMG or 869. I know Kirby says he's not keen on H50BMG but we've fond it really useful in factory RUM's. It does get rid of barrels quicker than the other 2, but that means you'll get annew match barrel on their sooner!
Seat the SMK's out until you've still got 100 thou of parallel in the case neck, and they'll easily shoot under .5 MOA unless you got a real dog of a Sendero. If you seat them to fit in the mag, they'll probably still shoot ok, but they shoot more consistently seated out as far as you can with still 100 thou holding in the neck.
Once you rebarrel with a custom short, tight throat, then you have a far larger range of bullets that will work. The 7mm RUM is an awesome long range hunting round as Kirby say, so long as you don't treat it like a high volume varmint rifle!
Greg

 

[Airgunner7]

Good thread...not too much info on 7 Rums.

Been playing with mine for a year with 180 Berger vdls and 160 Accubonds.

How high can I go with retumbo and 180's?
Berger sent me quick max load of 86g @3050....I see one other fellow here did 92!!!

I have gone to 86.5 @ 3010 and and settled on 85.5 @2960....I feel like I am not using the advantage of the Rum.

Anyone else have problems with primers not hot enough to light powder? I use cci 250's and was thinking about 215m's?

 

[theflyonthewall]

Hey guys. I have a question here.....

The 7RUM is a cartridge that I find really interesting and was wondering about your thoughts. This seems like a near perfect dual-purpose elk/whitetail cartridge for me. I have yet to go out west to hunt elk, but I hunt a lot of whitetails. the question is:

Is there any potential to get ....say.... .6 accuracy or thereabouts with reduced loads in the 7RUM? I ask because if I were to rechamber my current rifle in the 7RUM someday, I want to be able to have a decent amount of barrel life and was thinking that reduced loads would have to help with that.

Why reduce loads in the 7RUM when I could go with another lesser-capacity case? Because I could turn up the horsepower and have a great elk round if the need ever arises.

So can reduced loads give solid accuracy in the 7RUM?

 

[WildRose]

Hey guys. I have a question here.....

The 7RUM is a cartridge that I find really interesting and was wondering about your thoughts. This seems like a near perfect dual-purpose elk/whitetail cartridge for me. I have yet to go out west to hunt elk, but I hunt a lot of whitetails. the question is:

Is there any potential to get ....say.... .6 accuracy or thereabouts with reduced loads in the 7RUM? I ask because if I were to rechamber my current rifle in the 7RUM someday, I want to be able to have a decent amount of barrel life and was thinking that reduced loads would have to help with that.

Why reduce loads in the 7RUM when I could go with another lesser-capacity case? Because I could turn up the horsepower and have a great elk round if the need ever arises.

So can reduced loads give solid accuracy in the 7RUM?

7mm STW is the answer vs loading the rum down.

 

[Airgunner7]

I average .75 ish even with some bad primers( I think) . Almost all groups are below 1 moa. Stock Sendero 26"

Went out to a local mile shoot and rang the gong at 1804Y...even with some problems with my reloads.gun)

 

[theflyonthewall]

7mm STW is the answer vs loading the rum down.

In your opinion W.R., would I be looking at nearly as short of a barrel life with near max loads in the STW as near moderate loads in the RUM? I know I'mkinda picking the fly dung out of the pepper here....lol. But in a way, isn't that what we're all doing in long range equipment?

I average .75 ish even with some bad primers( I think) . Almost all groups are below 1 moa. Stock Sendero 26"

Went out to a local mile shoot and rang the gong at 1804Y...even with some problems with my reloads.gun)

Wow....nice going on the gong! Is that .75-ish with a reduced load or near max loads?

 

[Sako7STW]

7mm STW is the answer vs loading the rum down.

A STW is hardly a loaded down Rum. Maybe a 7RM or 7WSM or .280 Rem.. Thats almost an insult to the STW.

 

[WildRose]

A STW is hardly a loaded down Rum. Maybe a 7RM or 7WSM or .280 Rem.. Thats almost an insult to the STW.

No it isn't. Smaller case, less powder, lower recoil, and out to 1000yds every bit as deadly as the Rum on deer sized and smaller game/varmints.

 

[WildRose]

In your opinion W.R., would I be looking at nearly as short of a barrel life with near max loads in the STW as near moderate loads in the RUM? I know I'mkinda picking the fly dung out of the pepper here....lol. But in a way, isn't that what we're all doing in long range equipment?





Wow....nice going on the gong! Is that .75-ish with a reduced load or near max loads?

When you compare similar bullet weights the powder charge is significantly smaller.

Looking at 162gr bullets STW load with H-1000=78.2gr=3150fps vs Rum 87.3gr=3100fps.

That's a much more efficient use of powder for nearly the same result with a significantly reduced blast and lower recoil.

It's also going to tend to produce better barrel life.

 

[Airgunner7]

This is really splitting hairs as we are talking small margins here. I don't think anyone can say the 7 rum is not the ultimate hot rod here...it wastes powder like funny car burns fuel. I would love a stw though, as it might last a tick longer and use less powder. Pick your poison

here are my log #'s for a 160 Accubond
Retumbo CCI Virgin Nosler Brass
90.0G 3234,3240, 3237
92.0G 3305, 3310, 3300
94.0G 3398,3389, 3413 getting sticky

 

[theflyonthewall]

When you compare similar bullet weights the powder charge is significantly smaller.

Looking at 162gr bullets STW load with H-1000=78.2gr=3150fps vs Rum 87.3gr=3100fps.

That's a much more efficient use of powder for nearly the same result with a significantly reduced blast and lower recoil.

It's also going to tend to produce better barrel life.

Sure would be nice if some brainiac would work out a realistic formula for case volume vs. charge weight vs. barrel life. I know, there's considerably more to consider in making such a formula. But it sure would be nice if it could be done.

And yes WR, the lesser amounts of powder in the STW would definitely equate to longer barrel life if all other things were kept equal between them.

This is really splitting hairs as we are talking small margins here. I don't think anyone can say the 7 rum is not the ultimate hot rod here...it wastes powder like funny car burns fuel. I would love a stw though, as it might last a tick longer and use less powder. Pick your poison

here are my log #'s for a 160 Accubond
Retumbo CCI Virgin Nosler Brass
90.0G 3234,3240, 3237
92.0G 3305, 3310, 3300
94.0G 3398,3389, 3413 getting sticky

I LOVE that funny car analogy!...lol. So true.

 

[submoa1000]

I have really enjoyed reading the posts on this forum!

I must say however as an owner of many long range rifles, I have been drawn back time after time to the ballistics and the performance of my 7 Remington Ultra Mag. I have had my action re-chambered to a 7 Tejas Ultra Mag. This squares the shoulder and allowes for around 5% more powder. However, I am back to what works best with the least amount of pressure.
I believe anyone who does not shoot the 180 Berger VLD in this caliber is absolutely crazy. Of course, I have a custom 26" PacNor barrel, but it should not matter. I am loading it at 3.670 O.A.L. or 2.970 on the ogive to make sure it fits in the magazine. I have been lucky to not have to seat into the lands as my accuracy is 7/16 or better at 100 yds. and sub moa at 1000 yds!!!
load data
93.5 grains of Retumbo (3190 fps)
180 Berger VLD Hunting Bullets
Federal 215 Match PRimers
Remington Brass
Hornady custom competition dies(reamed for the Tejas)
.001 Runout(concentricity)


Do not waste your time with any other powder as they are way to tempeture sensitive. I tried US869, H1000, and Re 25, non of them produce the speed and accuracy of Retumbo!!!
Make sure to sight your gun in at a minimum of 500 Yds and work your drop charts from the longer ranges. I have used both the turrets and nightforce ballistic software. They are both sufficient to make kills at extreme long range. I would also highly recommend a Co-Sign indicator for elevation shots.

This set up in my opinion is proved to be the best long range set up period!!!

I know there are many calibers out there. I also shoot a 300 RUM, 30-378 Weatherby and 25-06 Rem. Love them all, but the first gun I grab when going big game hunting is the 7 Tejas! My best friend just dropped his cow elk at 1240 yds

Good Luck, hope this helps...