Ballistics calculations

[HashBrown123]

A question for the wider community as a whole.

When sitting down and working out your ballistic tables for your airguns what information specifically do you find useful and what do you want to discover exactly.

I see lots of programs and apps for calculating this stuff but I am not sure they are all that useful. What am I missing.

 

[Trucker3573]

I believe they basically all calculate the same thing. I find them very helpful. Important factors are BC, scope height and an accurate zero at whatever starting point you choose. I think a lot of the other elements are a bit minor for the closer ranges most of us use air rifles. The trickiest is the scope height.
I use the element optics app. It has the BC of a lot of pellets built in if you don’t have a chrono that will calculate that.

 

[shambozzie]

+1 on everything Trucker3573 said. Add agood range finder and bingo.

 

[blueflax]

They are helpful. I feel that you have to back them up with some range time. I use American Airguns Trajectory Calculator.

 

[JimD]

I agree with bluefax. I like to shoot groups at various distances to check the ballistics program. Often I change the bc a little to get better agreement with the shooting results.

 

[lbc_PSI]

Do any of the airgun ballistics calculators just use two shot in distances to generate the drop tables?

 

[shambozzie]

With Strelok pro just use trajectory validation

 

[elh0102]

I guess I'm just old school (definitely old). By the time I figure out the calculator, I can usually have my solutions from shooting at the range. I've never seen a program that precludes shooting for verification, so I just skip it.

 

[Trucker3573]

+1 on everything Trucker3573 said. Add agood range finder and bingo.

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Oh yeah def need the range finder. Have to know the distance..lol. OP I would just pick a distance you are comfortable that you are going to shoot pellets into the same spot for your zero. That is very important especially your up and down. Needs to be on. I then roughly estimate with calipers my scope height. Then I move the target really close like 10 yards. Put your info (BC , speed, scope height and zero range) into a calc. Then punch in 10 yards for distance. Dial up what it tells you. Shoot at 10 yards. If your POI height is off adjust your scope height in the app until your poi is spot on matching the dial that the calc gave you. When doing that step do not touch scope elevation turret ( after you dial the scope for 10 yard dist according to calculator)only change scope height in the calculator. After that you should find everything is pretty darn close as long as your gun is shooting approx the same speed and the bc info is good. I don’t have a chrono that calculates BC so I use the number in the element app. Seems to work well out to the max 73 yards I have in my experiences.

 

[lbc_PSI]

With Strelok pro just use trajectory validation

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That’s sort of what I meant but not. The way certain archery programs do this is:

Measure peep height above the center line of the arrow while at full draw. This would be the same as scope height above the bore.

Provide an approximate drag model from the arrow..shaft length, weight, and OD, with fletching type and offset. This would be the equivalent of a drag model and BC.

Sight in at distance one. Record the sight mark on the sight scale. This would be the same as the up/down turret reading on the scope.

Sight in at distance two, adjusting the up/down turret until zero is established for the second distance.

The program can now calculate a start velocity from the provided data that should match the trajectory for the scope height and the two marks.