I have a question regarding setting up for a 500 ard Competition. Can I use a ballistics program and enter the following parameters Bullet Weight, BC , sight over bore , etc and use 500 yards as the sight in distance. Calculate a firing solution based on the criteria ive given and use the 100 yard rise value to set up the scope for the 500 yard shot. By that I mean at 100 Yards the bullet is 7.5 inches high. If I set up my scope so that it shows 7.5 inches high at 100 yards will I be right on at 500 Yards ?
500 Yard Ranging
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If all your inputs to the ballistics calculator are correct (mass, velocity, BC and sight over bore most important) you should be pretty close. You need to make sure that your scope crosshairs are level to the scope base and that the crosshairs are level when you adjust your zero. Most calculators probably do not include spin drift, but that is not likely to be a large factor at 500y.
Maybe we are saying the same thing, but you do not want your scope showing high at 100, you want your POI 7.5" high at 100 yards.
Maybe we are saying the same thing, but you do not want your scope showing high at 100, you want your POI 7.5" high at 100 yards.
If all your inputs to the ballistics calculator are correct (mass, velocity, BC and sight over bore most important) you should be pretty close. You need to make sure that your scope crosshairs are level to the scope base and that the crosshairs are level when you adjust your zero. Most calculators probably do not include spin drift, but that is not likely to be a large factor at 500y. Maybe we are saying the same thing, but you do not want your scope showing high at 100, you want your POI 7.5" high at 100 yards. Yes I set the scope up using a laser bore sighter showing the point of impact at 7.5 inches whith the cross hairs 7.5 inches lower than the laser dot.
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You need to zero your scope at 100 and then plug in your atmospherics for that zero session.
on the day u want to shoot 500 you tell your calculator what the atmospherics are on that day. The computer will make all the calculations and give you your drop and/or click value.
I use "bullet flight". Another good one is " Applied ballistics. "
I use a kestrel meter for my atmospherics.
Have fun.
on the day u want to shoot 500 you tell your calculator what the atmospherics are on that day. The computer will make all the calculations and give you your drop and/or click value.
I use "bullet flight". Another good one is " Applied ballistics. "
I use a kestrel meter for my atmospherics.
Have fun.
Maybe we are saying the same thing, but you do not want your scope showing high at 100, you want your POI 7.5" high at 100 yards. Yes I set the scope up using a laser bore sighter showing the point of impact at 7.5 inches whith the cross hairs 7.5 inches lower than the laser dot.
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You need to fire the same live rounds that you plan on using at 500, and then adjust the scope so that your rounds are impacting X inches above your point of aim.
Using a laser bore sighter will get you onto the target backer at 50 or 100 yards, but it is not going to show you the real POI. Laser guides are not usually exactly centered in the bore, so either your elevation, windage or both could be off. Also, even if the bore sighter is exactly centered, it shows the bore axis, not the POI - you already have some bullet drop at 100y, although not much. Live rounds also put the barrel under stress so it flexes to a small degree causing the bullet to impact in different places with different loads. With a sporter contour barrel, I can get my POI to move nearly 2MOA with loads that vary by a grain of powder or so.
The short answer - you need to shoot the live rounds you plan to use at 500 if you want to get close to paper.
I had the competition As a FYI to everyone I was shooting 750 Grain AMX 50 Cal BMG. I sighted the rifle in at 100 yards. I had it dead on. I the ran my balistics calculations for a 500 yard zero using the same load. This showed at 100 yards the bullet would be 7.5 inches igh. I then used a laser bore sighter to set the point of impact at 100 yards to be 7.5 inches high and verified the impact point shooting 3 rounds. I was 10 inches low my first shots at the competition. I then adjusted the scope up 1.8 MOA. I was the almost dead on the bulls eye. I shot a 3 shot group of 1.25 inches
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