.308 Load, and Optics for Long Range M1A (M21)


Well-Known Member
Jan 27, 2008
My Springfield M1A (M21) can group well under an inch with 168 SMKs, Lapua brass, CCI 34 primers, and 40.5 grs. of H4895.
I haven't tried past 100 yards yet, but, since I've been looking at buying a Zeiss Conquest Rapid Z 800 or Z 1000 scope, the dope on their website has caused me to recently write the following:

'Been doing some hunting for the best scope for my Springfield M1A (M21).

Springfield Armory Rifles


Both are around $925
And both are 4.5-14x50

Note: Please enter your information into our Rapid-Z Calculator to ensure that you make the best possible reticle selection
based on your caliber, bullet, hunting conditions and location.

According to their calculator for the Rapid Z 1000 (designed for the .308 Match ammo):
This IS the value for .308, Sierra 168-gr. MK (BC =.462),
Velocity: 2,550 fps,
Elevation: 4,500 ft. ASL
Temp: 80 degrees F

The Rapid Z 1000:
With their calculator, and the scope power ring set to 11.87 (12 power):
They say to zero dead-on at 500 yards with the Bar 5. (Bar 5 is the center crosshair.)
At Bar 1, the bullet will impact at 154 yards (and you can zero at 154 yards with Bar 1, on 12 power).
(Bars 1 - 4 are above the center crosshair Bar 5.)
Bar 2 = 224 yards
Bar 3 = 316
Bar 4 = 406
Bar 5 = 500
Bar 6 = 595
Bar 7 = 692
Bar 8 = 791
Bar 9 = 892
Bar 10 = 993 yards
This is seemingly unbeatable.

Now, with the Rapid Z 800:
With the M1A, same load, they say to put the power ring at 14 power.
Sight in at 1.77" high @ 100 yards for a 200 yard zero (Center Crosshairs - call it Bar 1).
(All other Bars are below the center crosshairs - Bar 1.)
At Bar 2 (an unmarked bar), bullet will impact at 295 yards.
Bar 4 = 395 yards
Bar 5 = 495
Bar 6 = 596
Bar 7 = 698
Bar 8 = 800 yards

I know it's not a 1,000 yard reticle - but 'tis rather versatile anyway...

:rolleyes: So, I'm deciding on which to choose.
More field of view at 12 power with the Z 1000, than at 14x on the Z 800.
And the Z 800 is intended for other calibers; but, look what it does for the .308!

But, if you definitely need it backed-off at the lowest 4.5 power also, then the Z 800 will work for both close-quarter, and long-range work.
At 4.5 power, just use the center crosshairs for 0-300 yards - then for precision: Zoom to 14x for 200-800+yards.

Q. What would the Z 1000 do at 4.5 power? - when it is set up for all ranges (100-1000) at 12 power?
A. Dead-on at 500-yards ONLY - Center Crosshairs - Bar 5.

Maybe we can't have our cake, and eat it too. :D

So, for me, THE DECISION IS: Z 800 !

The Z 800 is more traditional and more useful under stress. Your short-range field of view (FOV) and accuracy (at 4.5 power) could mean everything.
I'd stress more over the up-close and personal - than sweat the remaining 200 yards down range to the magic 1,000 marker.

But, for a dedicated LR benchrest set-up - or if you don't mind having it at 12 power all of the time, the Z 1000 scratches the 1,000-yard itch.

[email protected]

You can check-out their reticles here:
Zeiss Rapid Z 1000
Zeiss | 4.5-14x50 AO MC Conquest Riflescope | 52 14 90 9973

Zeiss Rapid Z 800
Zeiss 4.5-14x50 800

LRB 7x50 laser rangefinder binoculars


Almost. :)

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