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HiBC · May 12, 2009, 02:52 PM

I just picked up my Sierra loading book and pulled out some interesting data.

I realize published data does not favor the full potential of a 7 Rem mag

But the Sierra recommended hunting load for a 160 Spitzer boat tail was 2900 fps.
The recommended hunting load for a .308 165 gr load was 2670 fps.

In each case ,we are playing by the same rules,Sierras recommended hunting load.

Using the criteria of a +/- 5 inches in trajectory,what sierra calls "Max point blank range",the 308 is 320 yds,the 7 mag is 345 yds.

We can quibble over shades of grey,the point is part of the advantage to the long range high velocity magnum is imaginary.

If a person has the basic skill of using a duplex or other reticle feature to estimate range,the trajectory is friendly enough to cover for a bit of range estimation error.Wind and mirage still have some effect,but its manageable at the 300 something ranges

Velocity is high enough to get excellent bullet performance.Once the game has been sighted,all can be acomplished with confidence using only the scope and rifle at the 300 something yard range.

Now,I do shoot targets at 1000 yds,and more.I do have a Leica rangefinder,Sierra's ballistic software,a chronograph,and a 4.5 to 14 Leupold Mark 4 on Nightforce 20 minute bases .It has a Kenton knob calibrated for 162 gr Hornady SST's at 3050 fps at a 5000 ft elevation.Its on a 7 mm Rem mag Laredo.It's my "Watching over spring calving" rifle.

I just suggest game seldom holds a pose where I can see them at 600 yds.
At those ranges,30 yds or so of range estimation error can cause blown backstraps or a broken leg. A thread of wind in the canyon that doesnt touch the leaves can push my bullet.My animal can take a step as the trigger breaks.
Ah,but we can spot the game with binoculars,then switch to the laser rangefinder,then put it down and pick up the rifle and find a position.All of this requires moving.Motion is easily seen.It takes time.Has our animal moved?

Try,early in the morning,dawn,sandbag a riflescope on a target at 600 + yards.Wait till the sun begins to heat the ground,then without touching the scope,look again? How is the elevation? Off 2 or 3 feet?Mirage.It works the same as when we put a stick in water.The stick seems to bend.Mirage appears to move the target.

From the military sniper skills we have learned a lot,and we have new toys.Thats nice.Those military snipers are even better at sneaking up closer to their target that they are at shooting.

Anyway,I'm not a want to be sniper.I have too much respect for the real thing to entertain Walter Mitty fantasies.I know who I am not.

You all,live how you want to,but for me,hunting is different than that.

Unless maybe if I see a coyote....

May 12, 2009, 02:52 PM	#56
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,283	I just picked up my Sierra loading book and pulled out some interesting data. I realize published data does not favor the full potential of a 7 Rem mag But the Sierra recommended hunting load for a 160 Spitzer boat tail was 2900 fps. The recommended hunting load for a .308 165 gr load was 2670 fps. In each case ,we are playing by the same rules,Sierras recommended hunting load. Using the criteria of a +/- 5 inches in trajectory,what sierra calls "Max point blank range",the 308 is 320 yds,the 7 mag is 345 yds. We can quibble over shades of grey,the point is part of the advantage to the long range high velocity magnum is imaginary. If a person has the basic skill of using a duplex or other reticle feature to estimate range,the trajectory is friendly enough to cover for a bit of range estimation error.Wind and mirage still have some effect,but its manageable at the 300 something ranges Velocity is high enough to get excellent bullet performance.Once the game has been sighted,all can be acomplished with confidence using only the scope and rifle at the 300 something yard range. Now,I do shoot targets at 1000 yds,and more.I do have a Leica rangefinder,Sierra's ballistic software,a chronograph,and a 4.5 to 14 Leupold Mark 4 on Nightforce 20 minute bases .It has a Kenton knob calibrated for 162 gr Hornady SST's at 3050 fps at a 5000 ft elevation.Its on a 7 mm Rem mag Laredo.It's my "Watching over spring calving" rifle. I just suggest game seldom holds a pose where I can see them at 600 yds. At those ranges,30 yds or so of range estimation error can cause blown backstraps or a broken leg. A thread of wind in the canyon that doesnt touch the leaves can push my bullet.My animal can take a step as the trigger breaks. Ah,but we can spot the game with binoculars,then switch to the laser rangefinder,then put it down and pick up the rifle and find a position.All of this requires moving.Motion is easily seen.It takes time.Has our animal moved? Try,early in the morning,dawn,sandbag a riflescope on a target at 600 + yards.Wait till the sun begins to heat the ground,then without touching the scope,look again? How is the elevation? Off 2 or 3 feet?Mirage.It works the same as when we put a stick in water.The stick seems to bend.Mirage appears to move the target. From the military sniper skills we have learned a lot,and we have new toys.Thats nice.Those military snipers are even better at sneaking up closer to their target that they are at shooting. Anyway,I'm not a want to be sniper.I have too much respect for the real thing to entertain Walter Mitty fantasies.I know who I am not. You all,live how you want to,but for me,hunting is different than that. Unless maybe if I see a coyote.... Last edited by HiBC; May 12, 2009 at 08:21 PM.