CCI Standard velocity discrepancy 300yd drop

[callen3615]

Hey guys, I was shooting my savage mkii today at 300 yards. I was able to get on target (18x30 piece of sheet metal) in 4 shots. From a 50 yard zero my elevation dope was 10.5 mils. I am shooting cci standard velocity 1070fps.

I got home and plugged in the cci standards BC and MV and zero and came up with totally different numbers.

From my calculations I get 108" of drop from a 50yd zero:

10.5 mils X 3.438(moa conversion)=36MOA

36MOA at 300 yards = 108 inches of drop

But from this ballistic calculator it states 166" of drop???

Any help? thanks

 

[clayne_b]

Re: CCI Standard velocity dependency 300yd drop

maybe the bc is off? try .145

 

[callen3615]

Re: CCI Standard velocity dependency 300yd drop

I dont think the bc is off. it would have to be infinitely higher to meet the 108" at 300.

If my zero was off, it might make sense. If my 22 was zeroed for 160 yards I would need roughly 106" of correction to make it the additional 140 yards.


Could my rifle be zeroed for 50yds and 160yds? Like a battle zero?

I did some trigger work saturday and while I had it in pieces I tweaked with the scope and added a shim between the rear scope ring and scope. I did rezero at 50 yards but never checked past that.

 

[callen3615]

Re: CCI Standard velocity dependency 300yd drop

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DFOOSKING</div><div class="ubbcode-body">
What's up with the 160yd zero? I doubt with match ammo you can "battle sight zero" your setup...just too much drop involved. You say you rezeroed after the shim....that may give more available elavation travel but it won't change your rounds ballistics. </div></div>

Just a guess.

I know it is on target at 50 yards, yet I only need 10.5 mils to get to 300.
Strange.

 

[TOP PREDATOR]

Re: CCI Standard velocity dependency 300yd drop

i was and is always a believer that the calculators are a good guide, but nothing beats factual field / range data.