Retumbo in 7MM Magnum...

[NDTerminator]

Howdy all. Recently began experimenting with Retumbo in my 26" Remington 700 LH 7MM Magnum, and am very happy with the results. 69.5 grains with a 160 grain Accubond yields 2980FPS and sub .5MOA accuracy. Shoots flat and accurate out to 400 yards, which is as far as I have to work with until we get some of the corn off around here.

Hodgdon's lists 69.5 as max for the 160 grain Partition but 73.5 for the 162 grain Sierra BTSP. The 160 grain Accubond is a lot closer to the BTSP than a Partition and 69.5 grains seems a conservative max, but I can't find any specific data for the Accubond.

Retumbo data for the 7MM Magnum is sparse and I'm wondering if anyone has any loads they worked up in this caliber?....

 

[Ernie]

Sorry, but no. I use H-1000 in mine (7 Rem Mag Imp) with 180 JLK's and Berger's.

 

[gei]

I load 71.5 retumbo and 168 burger safe pressures, and wonderful accuracy.

 

[Sendero_Man]

i shoot 168 VLD and 71 grains of retumbo. 3040 fps @ 4800 asl

excellent accuracy in my Sendero....

 

[4xforfun]

I have been an H1000 fan in the 7MM Rem Mag since it came out!!!! Basicly....if you couldn't get a 150-160 grain bullet to shoot with 71 - 75 grains of h1000.....it wouldn't shoot.....They ALL DID!!!!!!

But............................This year I tried RL 25 with JLK 168 and 180 VLD's in 3 different 7mm Rem Mags. WOW......every bit as accurate, but FAST........FAST.............FAST!!!!!!

I was getting around 3000 FPS with the 180 JLK out of a STOCK 24" 7mm ADL manufactured in the early sixties.............one of the first made, with eighteen cazillion rounds through it!! It shot great.

Out of a 26 " Hart with 168's we were getting .......well................I am ashamed to say it......1st 5 shot string..........A. V. of 3277 & 28 ES..............second 5 shot string, with a well warmed up gun..........A.V. of 3290 & 17 ES.!!! The only problem I had with this gun is the fact that this was the load that it shot best, by quite a bit, I might add. Since it was my brothers gun, and I am in his will, I gave it to him.

This is almost embarising, as the pressures had to be very high, but there were very little signs of pressure (except for the chrono readings). These strings were shot at night with a CED M2 with infra red screens.

I am guessing, based on my 300 WBY data with heavy bullets, that Retumbo would be just as good with heavy bullets in a 7mm Rem.

If I have time next spring I will try the Retumbo/JLK mix in the 7mm's!!!

I thought I was over the "SPEED IS KING" mentality...................Guess not.


Oh well, There is always next year.

 

[shootinfool]

I just started working on a load for the 160 gr ab and retumbo. I havent finished working on it due to a closure of my range for winter but so far 68.5 gr retumbo and a federal gm215m primer seated at 15 thou off lands and grooves gives me average velocity of 2920 fps. the gun is a rem 700 pss with a 24 inch factory barrel. groups at about 3/4 inch. want to do more work with this bullet and possibly switch and try rl22 or h1000 with it.

 

[txsendero]

For what it's worth, out of 26" Hart barreled Sendero 7mm Rem Mag, getting very good accuracy (consistent 1/2 MOA or better) with 168 Berger VLD @ 3065 fps with 72 grains Retumbo, WW brass, and Fed 215 primers. Very consistent velocity spreads after barrel break in. One cool thing I noticed was that as the barrel got more rounds through it, velocity increased a little bit, then leveled off.

 

[260shooter]

This is good to hear. I should pick up my 7 REM Mag in a week or so. 1-9 Broughton at 26". I have laid in a good supply of Berger 168's and Retumbo.

Any preference of bullet jumping or into lands?

Thanks

260

 

[Derek M.]

This is good to hear. I should pick up my 7 REM Mag in a week or so. 1-9 Broughton at 26". I have laid in a good supply of Berger 168's and Retumbo.

Any preference of bullet jumping or into lands?

Thanks

260

Berger recommends into the lands or at least at the lands. I tried this and found the 168 did well. It did even better with about 10 thou off lands.

73.0 gr of Retumbo is safe in my rifle but 72.5 and 72.0 shot best.

 

[Pdvdh]

74.9 gr Retumbo, 168 Berger VLD, Federal GM210M primers - my load in my 7mm Rem Mag rifle.

My barrel is 24 2/8" long and my MV = 3080 fps.

Bullets loaded 0.006" into the lands shoot very well for me. I've never tried the VLDs backed off the lands as they shoot very well loaded into them.

 

[Derek M.]

74.9 gr Retumbo, 168 Berger VLD, Federal GM210M primers - my load in my 7mm Rem Mag rifle.

My barrel is 24 2/8" long and my MV = 3080 fps.

Bullets loaded 0.006" into the lands shoot very well for me. I've never tried the VLDs backed off the lands as they shoot very well loaded into them.

This has always interested me. I have been told by some with many years more experience than me that a standard primer, especially in a 7mag, creates a very uniform burn for the column of powder and accuracy is stellar.

~ 75gr of Retumbo is a good stout load. I may have to monkey with this and use a standard 210M primer to see what happens.

 

[Pdvdh]

I found that the non-magnum primers yield lower extreme spreads and standard deviations in fps velocity. Don't use a magnum primer with my 74.9 gr powder charge without working up to it cautiously, as it will likely be one fiesty load.

Regarding the non-magnum primers, I've experienced the same thing with my 300 Win Mag. When you drop down to the standard large rifle primers you may see a decrease in MV and then have to increase the powder charge a tad to get back up to your maximum charge.

 

[linksmechanic]

68 grains of retumbo with the berger 180 jammed into the lands. 2950 fps. No pressure in this gun. Fed 215m primers. Norma brass. Accuracy is rediculous. All from a sendero sfII.

 

[KQguy]

As soon as I get my rifle(7mm WSM) back from my gunsmith,I am going to load develope using Fed210M's.I was told by a competitve BR shooter,that would be the best primer to try,unless I was planning on shooting in extreme cold weather.The good thing about the 210's,you can find them fairly easy right now,unlike the 215's.