Speed vs accuracy in 7mm rem mag.

[Benchguy57]

So I just would like to see what you all recommend.
The rifle is a mostly stock Remington 700 bdl stainless in 7mm Remington mag 26" (?) barrel but don't quote me on that.
The load is
Nosler 140 grain accubond
64.7 grains of. H4831
Nosler brass
Cci 250 mag primer
Coal is 3.350"
Bullets are all touching at 100 yards consistently more than a fluke lol.
That last couple of trips out I've shot the same, but the problem is the velocity is around 2850 fps.
I would like to get it up closer to 3000 fps but not sure if I should mess with a good thing,
Not that a deer would be able to tell the difference lol.
I hunt mostly wooded land with a possibility this year to hunt over a few bean fields by Truman lake where a 500 yard shot would be possible.




Thanks for your input.
George.


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[flyrodder]

In my opinion, consistent accuracy is far more important than velocity. Other than often minor increases in maximum point blank range and retained energy, increased velocity offers decreased barrel and component life. And, unless you are always taking shots within your MPBR, you'll have to go to holdover or turning turrets at some point anyway.

You might want to check that velocity. I only have a Chrony so the data may be suspect, but my 280 AI is showing about 2,930 fps with 140 Ballistic Tips over 58.0 grains of IMR 4831, Nosler brass, CCI Large Rifle primers. That appears to be a good MV as it ties with my Zeiss Rapid Z out to at least 575 yards.

 

[Graham]

Speed vs accuracy in 7mm rem mag.

There are accuracy nodes all over the velocity spectrum with a big 7mm.

There's sure to be one somewhere either side of 3000fps.

But you don't need a magnum at 3000fps to kill deer at under 500 yards.

 

[Clark]

70 gr H4350 140 gr Nos BT is 11 gr over max Hodgdon published load.
At 477 yards it flipped him over with all 4 hooves in the air and made a big exit hole. The hollow pop sound was like a prairie dog being hit.

It didn't hurt to have excess power, but it sure was excess.

 

[ahhshoot]

I'm shooting the same rifle and you should be able to find a better node around 3100 fps. I was running 65.9gr of H1000 behind a 140 gameking hpbt and had great results. I decided to bump it up to 71.5 grains and still no pressure signs. I have only shot one group with this new load so far but it was 5 shots and measured .386" at 110 yards. That's better than my custom guns typically shoot and this thing weighs 8 lbs with a 9x scope. I went back inside, made 20 more and now they are waiting for hunting season.

I would try working up to whatever load will get you to around 3100. That's some snot from a 140gr projectile and definitely getting your moneys worth out of the big seven. Fyi this was with FC brass, gm215m primers and seated 20 thou off lands.

 

[hermosabeach]

There are plenty of loads to send a 160 grain spitzer 3,000+ FPS

140 Grain load with good accuracy makes sense to me....

Unless you are hunting a bigger ammo where you need more cross sectional density and energy, don't sweat a great load...


the 7 mag has a good case capacity to the diameter so you can load a "barrel burner" and punish yourself with more recoil... why????



Here is the BArnes factory ammo load data
SKU# Cartridge Bullet B.C. grs muzzle 100 200 300 400 500
21526 7mm Rem Mag TTSX .412 140 3100 2865 2642 2429 2227 2034

 

[No1]

I like accuracy myself, but I also like flat. one of my best 7RM loads is
65.6g H4831
SMK 168 HPBT
Rem 9 1/2M
2925fps from a 26" barrel

I've had good results with RL22 and 145g bullets.
67.5g Reloader 22
Speer 145g BTSP
Rem 9 1/2M
3130fps

 

[Sniper260]

I wouldnt worry about it if it shoots great right there... your adjusting elevation is what your turrets are for. if you wanted to get a little more velocity I would look at trying some H1000. 4831 is a slower burning powder.

 

[Benchguy57]

Thanks guys for all the replies. Greatly appreciated.


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[No1]

I wouldnt worry about it if it shoots great right there... your adjusting elevation is what your turrets are for. if you wanted to get a little more velocity I would look at trying some H1000. 4831 is a slower burning powder.

H1000 is slower than H4831.

 

[Powermac]

Try a slower and more appropriate powder then the H4831 in your 7RM and you should have better luck with your velocity.
For a comparsion my shehane with a 26 bbl, lobs the 180's around 2950 with N560, with almost 10 grain less of powder.
A case for witch the 4831 is about ideal.

VV N165 ,170, and N560.
Norma MRP and MRP 2.
Hodgon H1000 and Retumbo.
Aliiant RL 22 and 25.
And possiby IMR 7828.

All these powders are better suited for the task, and probably more that i do not know, never shot any IMR or Alliant though as they are not available here.
RL 22 i know as it's basically Norma MRP.

Norma MRP /RL 22 tends to give very good velocity in my 7 RM, have yet to find a powder that gives as good velocity with lighter bullets, but it's temperature stability is rather horrible compared to some.
If i was you i would firstly try some H1000 and N165 or 170, they are all very clean and cool burning powders with good temperature stability and tend to give good velocities.
Retumbo and N560 is also good options, but harder on the throat.

 

[Sniper260]

H1000 is slower than H4831.

You are right, I looked it up after I posted because I second guessed myself about 5 min later haha. I stand corrected!

 

[Benchguy57]

Well, I went out to my local reloading shop and found some Re-22 and retumbo.
Now all I need is a trip to the range to see how they shoot.
Thanks guys for all the help.



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