I need shooter app help please

[upacreek]

My rifle is a 7mm Rem Mag with a 26" lilja barrel, 1:9 twist. I have been working on load development for awhile and have been pretty happy with 70.5gr rotumbo under 180 Berger hybrids. Behind my house I can make 2000yrd shots if I want to set up a target that far. Having settled on 3050fps due to plotting different ranges fairly accurately (I don't have an accurate chronograph) I finally stepped past 750 yards yesterday straight to 1095yrds. To my surprise things were way off. My shooter app came up with 23.9moa. It took 4 shots to come down far enough to hit the steel. Settling on 20.25 moa I hit the steel, and 3 consecutive times after that. My steel is 21" round.

So what did I enter wrong?

Today I only had 2 bullets left of that load, and my targets were still up, so being the show off I am to my family I nailed my 740yrd target (8"x14"), and missed my 1095 target. Quite embarrassing.

How can I determine where my 3.25moa discrepancy is and what is the best method for entering the altitude/weather info?

Thanks for any help.

 

[Greyfox]

It's hard to tell without seeing your entry data for your rifle and bullet. I played around and tried plugging your provided data into my Shooter program for 1095 yards using a 200 yard zero, G7 formula, 1.75" scope height, 3000ft alt, 40 degrees temperature, no coreolis, and zero angle, I get an elevation adjustment of 23.7 elevation at 1095 yards. Comparable to your data. When I plug your actual adjustment into the velocity calibration function it shows a correction of over 200FPS higher. This is an unlikely velocity for your load in a 7mag.
I would first check to make sure all my entry information was correct , particularly your angle. I would then look to my scope, mounts, bedding, and shooting platform/technique.

 

[oldno7]

Lots of change will occur with your zero setting, as well.

I would confirm your zero range and go from there.

 

[upacreek]

Thanks for the input. My zero range is 270yrds. I didn't however realize I was using a g1 setting instead of g7. I have been reading some on the shooter app and still don't understand some things.

It is possible my range finder was not accurate because of the snow around the target. Holding a rangefinder steady is difficult. The way I knew to drop my poi was because I could see the impact in the snow.

I am not sure what setting to use for weather data input. I just opened up shooter and selected 1095yrds and the call was for 18.1moa. This alarmed me and I realized in the atmosphere section calls for 17.6 degrees. A value I wouldn't have entered, but is accurate right now. Humidity calls 75.4 and wind speed 4.47mph at 90 degrees.

Where does this info come from?

Last September when I got this batch of bullets loaded I manually entered my atmosphere, and have never noticed it being entered automatically. My zero target just happened to be at 270 yards. My sight height is entered as 1.5". Is it gonna make much difference?

I will continue to read what I can.

I will be loading another 100 rounds this week. I don't know what else to do except start over and enter the cleanest data i can at the time.

 

[mikebob]

i used shooter for awhile until i got a windows phone. i believe there is a setting for atmosphere zero and a setting for current conditions. im pretty sure there is a check in setting to auto populate current atmo using internet data. also if you use no altitude and absolute pressure when zeroing in you need to check the box or it wont work.. dont quote me though been a while since used it now i use a program on my windows phone that is much simpler. all setting on one screen in tiles its called nimoh ballistics.