Retumbo-7mm RM

[jwrowland77]

I was looking on Hodgdon website and my manuals. Plan to use 160-170gr bullets. I noticed on Hodgdon website that the MV was good and pressures were lower than other powders for a 162gr bullet. Hodgdon showed 69.0-73.5C. 2963 on upper end of MV.

I picked up a pound to test out, and try and make a precision load for long range, 1000yd+ range.

I was just mainly looking for reviews on Retumbo from fellow reloaders and see how they liked it.

 

[JimKirk]

JW ... I have used Retumbo in .264 Win and .270 WSM with good results ... velocity is great and accuracy is also ... if there is anything if you could say negative ... it is a little sooty ...

 

[Cycletroll]

I have used Retumbo in a 26" Barrel Remington 700 & mag with 180gr Berger bullets (among others). IME Retumbo works best with heavy bullets and high load density. I was able to fine a really nice load with an SD of 6fps that shot those 180 Bergers at 2980fps into .57 MOA@335yds (1.6" 3 shot group). I was a bit above book max but my COL was long and the Bergers have relatively short bearing length. I think it is an excellent powder for 7Mag. H1000 and R33 are good too.

 

[jwrowland77]

That's good to hear. I have a Rem 700 with 26" barrel as well.

I'm looking at running either the 180gr Bergers or 180gr SMK. I was leaning towards the Bergers since I wouldn't shoot it often.

My goal is to have a 1500yd load.

 

[Cycletroll]

In my 700 loading at the lands (about 3.46" IIRC) and 71gr Retumbo gave me 2980fps. Measure your guns throat and work up to be sure.

 

[jwrowland77]

Oh yeah. Always!

I have to Rem 700's and both have extremely long throats. My .308, I load my match ammo to OAL of 3.000, ogive 2.3520. My 7mm RM is the same. My hunting ammo for that one using a 139gr Hornady BTSP is at 3.300

 

[gamestalker]

I've tried it with 7mm RM, and didn't care for it much. A good friend of mine talked me into trying it, but the first thing I noticed with it, is I had to sacrifice, and you know me, I won't give up my velocity. I stick to RL22, or IMR-7828 mostly.

As for accuracy, it wasn't terrible, but it also wasn't as accurate as my 7828, and certainly not as good as 22. I also gave RL25 a run, and that was pretty darn accurate, but velocity was an even bigger sacrifice.

GS

 

[Cycletroll]

Gamestalker,
You saying you can push a 180gr Berger faster than 2980 with R22? That has got to be a seriously high pressure load given that R22 is considerably faster than Retumbo. I can get the same velocities with Reloader 33 but no way with R22. As far as accuracy 1.6" at 335 yds for three shots is nothing to sneeze at for a stock Remington.
Of course every rifle is different but for my money Retumbo and R33 are tops for fast accurate heavy loads in magnum cases with H1000 a close third.

 

[gamestalker]

No, not 180's, the OP was referencing 160's and 170's. I don't load a bunch of 160's or 170's, but I've been there, done that with good results.

And yes, with the right powders, right bullets, the 7 mag will get 3000+ fps with a 160 gr. bullet, and without having to get into red line pressures, but getting them up there requires fully working them up.

My preferred bullet weight is 145, they fly nice and flat. And with the right bullet, 145's can be comfortably be pushed beyond 3200 fps..

That's my story and I'm sticking to it.

GS

 

[Cycletroll]

Got it Gamestalker. Ya I've pushed 160's to 3100+ and 140's to 3200+

My feeling is that velocity is temporary and bleeds off fast with a lighter lower BC bullet. The beauty of the 7 Mag is using super high BC bullets energy and velocity is carried much farther and of course have way less drift in wind.
The slower powders like Retumbo and R33 as well as H1000 seem to work better with heavier bullets and 100% load density if not slight compression.

 

[GooseGestapo]

If you're feeding a 7mmRUM, you owe it to yourself to go to www.gi-brass.com and look into the surplus .50bmg powders that Ron Bartlett sells.

I got some WC860 back in '05 to feed my .300RUM. Except for match/target grade ammo, I've gotten some excellent results with it. I bought the .300RUM and later, a .257wby just because of the inexpensive components...

I actually prefer RL25 to Retumbo, but that's just my gun. It "likes" RL25, but others including the $5/lb WC860 do well, too.

Stock up on some of the "blemished" 160gr or 175gr bullets MidwayUSA has currently and 16lbs of either WC862 or WC870 and you'll shoot out that barrel before you know it !!!

Cheaper to shoot than a .30/30 with "mainstream" components.

 

[gamestalker]

Actually, I believe the OP is referring to the 7mm RM, or Rem. mag, rather than the RUM, or Remington Ultra Mag.

GS

 

[jwrowland77]

Actually, I believe the OP is referring to the 7mm RM, or Rem. mag, rather than the RUM, or Remington Ultra Mag.



GS

That would be correct GS.

 

[jwrowland77]

Hey GS, does Lee make a Collet Neck die for the 7mm Rem Mag that's NOT in a 2-die set?

 

[gamestalker]

I don't know if Lee offer's just the single collet die, or if you have to buy the 2 die set. I only use the Lee handgun die's.

GS

 

[flashhole]

Yes, you can purchase the Collet Neck Die separately. Try FS Reloading.

Retumbo is my favorite powder for the 7RM for 165 and 175 grain bullets. I have a good stock of the Speer Magtech and Grand Slam bullets. Might be considered a bit much for whitetail deer but they bore fifty cent piece size holes clean through them and don't cause a lot of meat damage.

 

[jwrowland77]

Yes, you can purchase the Collet Neck Die separately. Try FS Reloading.



Retumbo is my favorite powder for the 7RM for 165 and 175 grain bullets. I have a good stock of the Speer Magtech and Grand Slam bullets. Might be considered a bit much for whitetail deer but they bore fifty cent piece size holes clean through them and don't cause a lot of meat damage.

Awesome. I tried looking for them but kept coming up with the two die sets.

I'll have to order me one tonight.

 

[jwrowland77]

Just checked. No bueno. Only die sets. I'll just buy the set. Oh well.