7mm Mag loads

N

ncrypt

New member
Hey guys. I'm working up some loads for 7mm Rem Mag. and I'm shooting for 3000 fps.

Browning A-Bolt with 26 inch barrel
150g Nosler Partition
WLRM Primers
Hornady Brass
H4831 SC Powder
OACL 3.290

Using my manual and the hodgdon site, I started at 60 grains and worked up to 62 in .5 grain increments. I got around 2800 fps with 62 grains with zero signs of pressure issues and my best group at 62 grains.

The Nosler site starts at 61 and goes up to 65 claiming just over 3000 fps.
http://static1.squarespace.com/stat...71141801750/7mm-Rem-Mag-150gr-version-7-0.pdf

So, my question..is there anyone else shooting a similar load that can share their experience going up to 65 grains with this powder bullet combo? Three grains over the Hodgdon max seems like a lot.

appreciate any thoughts
 
I assume you have a chronograph. Keep adding powder until you reach the max listed velocity in the manual. That is the max load with the components you are using and in your rifle. You may well reach that velocity before you reach 65 gr of powder. Stop at that point regardless of pressure signs.

I know some people would go farther and get speeds in excess of what is listed in the manual. It may or may not be safe, but that is what I'd do.

If you get good accuracy then you're good to go. If not then it may be time to tweak the loads and reduce the charge some.

You may find the need to use a different powder in order to get both accuracy and speed.
 
I'm looking at Lyman, and they are closer to Nosler than Hodgdon. I wouldn't be so fixed on velocity though. Thats more a matter of the test fixture used. I would keep creeping up until your group starts to spread, or velocities begin to spread, or at 65gr, whichever comes first.
 
With a 26" barrel 150 gr Nos Bal Tip 3.4" H4350 I get 3333 -3375 fps over the chrono. That is with a VZ24 and the only slim Lothar Walther barrel that Brownells sells.

It works in mule deer AND antelope.
 
With the 150 partition Nosler likes n160, that what my son uses with the 150 Btips.
With 4350, I could never get the precision I needed so I went with a 160 grn Accubonds and IMR 7828, now that is a great combo..
 
I used an estimator to fit Nosler's load data into Hodgdon's load data performance curve, and that got 3202 fps, and not the 3048 fps Nosler measured. So this load difference is some sort of artifact of the combination of different guns, different brass, different primers, and different lots of powder.
 
I worked up to 65 grains today. No pressure signs at all, but I'm a little disappointed with the numbers I'm getting. However I'm happy with accuracy. All groups were within 1" to 1.5", which is totally acceptable for a hunting rifle/me.

63- 2843
63.5 - 2870
64 - 2911
64.5 - 2926
65 - 2961

I thought I would see greater gains per grain. I'm thinking of working a little past 65 or trying a different powder, just because it's fun to shoot. ha
 
I'm thinking of working a little past 65 or trying a different powder, just because it's fun to shoot.
Click to expand...

You will see much more dramatic velocity increases with a different powder.
 
I think IMR 7828 is pretty close to H4831 (at least in my 7mm RM).

Gun: Stiller TAC 300 7mm Remington Magnum (26 inch bbl./1 in 9 twist)

Bullet: Nosler 150 gr. Partition
Powder: IMR 7828 65.0 grs.
Primer: Federal 215
Case: Winchester 7mm Remington Magnum
LOAL: 3.270 (2.744 Base to Ogive with Stoney Point)
Velocity: 3029.70 fps
ES: 38.75
SD: 14.59
Comments: Jam length 2.749 Base to Ogive with Stoney Point. Bullets seated for 0.005 bullet jump to lands.

For example, I didn't use the same brass but these two were pretty close in velocity.

Bullet: Sierra 168 gr. HPBT Matchking
Powder: Hodgdon H4831 64.0 grs.
Primer: Federal 215
Case: Federal
LOAL: 3.300 (2.742 Base to Ogive with Stoney Point)
Average Velocity: 2852.90 fps
ES: 44.38
SD: 20.19

Bullet: Sierra 168 gr. HPBT Matchking
Powder: IMR 7828 64.0 grs.
Primer: Federal 215
Case: Remington
LOAL: 3.300 (2.742 Base to Ogive with Stoney Point)
Average Velocity: 2851.65 fps
Extreme Spread: 41.73
Standard Deviation: 16.12
Comments: Once fired brass. Three shot group at 200 yards was about 1.5 inches.
 
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Mark Twain once said there are white lies, regular lies, black lies, and then 7mmRemMag published data;)

You may start to suspect when the 7mmRemMag can't keep up with a hot loaded 7x57 surplus Mauser shooting over a chrono.

I am hunting with 11 grains more than max published. I know where the thresholds are and I have lots of safety margin.
 
I was gonna say... I don't own or have experience with a 7mag but these all sound like really nutered loads considering the case capacity. My .270 will throw a 130 grainer 3150-3180 fps. My 30-06 is at 2900-2950 with a 165 grain bullet. I'm not being critical but I couldn't help to think you can get the same performance in smaller cases of the same caliber and save yourself 10 grains of powder per round. Except for Clark. Sounds like he loads em like I do:o
 
The 7mmRemMag was SAAMI registered in 1962 at 61 kpsi and it should have been 65 kpsi.
It was registered at 3.29" over all length and it should have been registered at 3.34".

But that does not go half way to explain why published loads are so wimpy.


There must have been a push to make the recoil less than a 30-06 or one blew up in an executive's face, or some idiot had a job that year, or someone hated Remington, ....... or something.

30-06 loads are not wimpy.
 
Clark,

From my experience, if I load close to the 61K max listed in the manuals, after the 2nd reload on the casing I'm throwing the brass in the scrap pile due to loose primer pockets.

Deer doesn't know the difference between 56K PSI, and 61K PSI...
 
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