7mm-08 problems...

[bk_tradguy88]

So i just got my new rig all set up and sighted in last week. Gear as follows.

Remington 700 sps stainless in 7mm-08(24" standard contour barrel)
Leupold VX-3 4.5-14x40
Leupold dual dovetail medium rings and bases
Hornady superformance 139grn sst's

I sighted in, but was a little shaky that day so I waited till today to shoot some good groups to test out the rifle. Rifle is sighted in 1" low at 50 yards, 1/4"-1/2" high at 100. A 4 shot group at 100 only had 1 flyer when i messed up my trigger pull. Showing from the other 3 rounds to be shooting <.5moa. So at this point i'm really happy. So let's stretch out to 200 yards on steel. Not trying too terribly hard i put 3 rounds on steel about a 2.5" group, but my hits in the steel looked a little low from where i was holding on the steel. So i walked downrange and i confirmed this so i set a paper target. Then i was very unhappy. My rounds are hitting about 8"-9" low at 200 yards!!! Any ideas fellas?
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[bk_tradguy88]

Here was my round at 100 yards.
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[LWD]

Hmmm. This is odd. You should only be about 3" low at that range. Could you have been shooting at 250 yards instead? That would account for the drop. It was a good group at 200?

LWD

[bk_tradguy88]

Hmmm. This is odd. You should only be about 3" low at that range. Could you have been shooting at 250 yards instead? That would account for the drop. It was a good group at 200?

LWD

I was expecting 2.5"-3" low at 200 as well. The group on still was about 2.5" but varied left to right mostly. But seemed about 8" under my point of aim so i went to paper to verify and paper showed 8-9" low 2 shots both about 1.5" right as well. This is at my home gun range and the 200 yards is correct.
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[RemMan700]

Pull up a ballistics calculator and run the data for the load that you're shooting and see what it should be.

[bk_tradguy88]

Pull up a ballistics calculator and run the data for the load that you're shooting and see what it should be.

I do everything from my phone and haven't found a ballistics calculator that is usable on my phone without buying an app(i'm cheap on some stuff). But the box shows this load at 2950 fps, though I'm unsure what i'm actually getting out of my gun with being 1" low at 50, 1/4"-1/2" high at 100, and 8"-9" low at 200 something isn't right. Accuracy is there so something else is going on. There should not be that change from 100-200.
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[texasrazor]

Try Gundata.org

[zac221]

Their website for that bullets shows if zeroed at 200 that its 7" low at 300. Of course that's if you happen to have same rifle they did that with. It sounds pretty close to right since its a factory load. Good shooting though. I reload a 25-06 with 100 grain sierras at 3050fps and its about 3-4" low at 300 being zeroed dead on at 100.

[jmeghunts]

Give me all the data on the ammo and I can post up a table for you. Velocity is the most important factor.

[bk_tradguy88]

Give me all the data on the ammo and I can post up a table for you. Velocity is the most important factor.

24" standard contour barrel remington 700

Hornady superformance 7mm-08 139grn sst
Box shows velocity at 2950fps

Say zero is 100 yards.

Thanks,
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[noflyzone]

How close is the objective end of your scope to the barrel?

Is there any way you have the "Rear ring" in the front and the "Front ring" in the rear of your dual dovetail base?

If so, this would serve to put you scope in a negative MOA and cause you to shoot much lower than your ballistic calculator is showing.


I don't know.............best guess..........

[noflyzone]

in medium height the rings are VERY similar. put a caliper on them to determine exact height of each and the taller ring should be in the back with the shorter in the front

[jmeghunts]

Here's what my shooter app come up with.

[jmeghunts]

This is pretty close I think. I have found this app to be very accurate on my .308 and 300blk stuff. Going to bed, PM me if I can help more.

[bk_tradguy88]

in medium height the rings are VERY similar. put a caliper on them to determine exact height of each and the taller ring should be in the back with the shorter in the front

I didn't remember seeing anything in my packaging so i went back to check. Nothing with the rings said anything about a front or rear ring. Nothing about different heights either. Broke it all down and put the calipers on them both. Identical down to the thousandths putting calipers on multiple points. Just for good measure i went ahead and swapped front/back and remounted.
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