Real World BC berger .25?

G1 BC = .466 (average from 3000 to 1500 fps)
G7 BC = .239

 

That number works real well with both my 25-06's.

 

.257 Weatherby

.25cal 115gr berger hunting vld

temp - 65

altitude - 1600

FPS - 3306 average

zero - 200yards

scope hight - 1.955

600yard = 7moa up this put me right on for elevation. three shots

900yards = 14.75moa up this put me my group center about 6 inches low. three shots

This puts me know where nere berger's BC and has made me want to go crazy for the last two years.

.6 works two about 600yards it seems to lose it's bc from there on out.

my scope is a Sightron SIII and as far as I can tell it tracks accurately.

 

Bryam Litz, the guy who replied to you, Berger's ballistician, is the one who derived those BC's, and all of the Bergers BC's They are about as real world as you're going to get.

 

Bryan's listed G7 BC of .239 works perfectly for my 257 Weatherby shooting 115 VLDs.

 

If you are dead on at 200 and 28 clicks at 600 and a calculated 61 clicks at 900, try a BC of .450 and a MV of 3527 fps. On the program I use this will be real close for the data you give. The one question I have is the scope height center of barrel to center of scope? I know the numbers don't seem quite right but try them and see if they fit.

Phil Conklin

An after thought, shoot some 5 shot groups at these same ranges and measure verry carefully. A 1/2 inch error at 200 or an inch at 600 can really mess up the results. Just a thought!

 

Another note on Berger bc's and Mr. Litz, if you observe something different he WANTS to know about it. And he will try to help you figure out why. You won't get that with most other manufacturers. His email address is very easy to find and he replies fairly quickly. One more reason I am completely sold on Berger Bullets. I don't shoot competitively and don't personally know anyone at Berger, but I can't sing enough praises for them as a company. They do business the right way. You pay a little more for their bullets but you get more and better service with them than you will with any other bullet manufacturer. And they are just plain deadly on game and accurate on targets.

 

I do agree about making sure it is perfectly zeroed at 200 and will try a 100 yard zero and go from there.

My velocity has ben checked through two chronograph's.

The scope height is center of scope to center of bore.

I do like these bullets and believe that they are the best .25cal bullet for long range. Though i do wish thay would get the 125gr .25cal bullets out soon.

I have killed two deer with them with DRT preformance.

 

Bryan actually could make his BC's more real world by abusing his rifles a little more.

 

I have only shot a few of the 25s but I know of the 500+ 130 grain 6.5mm VLDs I have fired from 3 lots I can mix and match and all groups look the same out to 200 yards. Velocities are consistent, I can punch in his numbers onto bergers ballistic calculator and my environmental conditions and they do just what it says they will (at least at the relatively short ranges I shoot). can't ask any more than that. Had one issue and I emailed him, and over a couple days he helped me iron the issue out.

 

I still stand behind the .450 BC and 3527 fps velocity in my earlier post. Those are the numbers that fit the data you provide. Did you shoot the data with a wind blowing from the left? If you are certain the MV is 3306 then some other factor is affecting your results.

After reviewing several ballistic programs and entering BC .466 and MV of 3306 with a 200 yard 0 , 8.4 MOA come up for 600 yards and 17.3 MOA for 900 yards. What are you using for your click value?