ballistics calculator tweaking

[Benjerman08]

I have a question I hope those with more experience can help with. It seems that ballistics calculators will be spot on for some guns and not for others. I have found that with both Pesja and JBM that I need to be about .5-.75 moa lower on my turrets than the program calls for to be on at long range. It is pretty much the same no matter what. My question is, how do I compensate? In the past I have just mentally subtracted. If I tweak the velocity in the programs, will it be accurate? Does anyone sight in low or high to compensate? I read that one can tweak the b.c. to do this, but I tried that and it doesn't make alot of difference. Thanks.

 

[blawton]

Yes either MV or BC is gonna get it done or both. But you still have to match it up to several known drops you have to make sure your getting it right. I just got a HTC ERIS w/ android software. There is a BC program called shooter on their that is awesome and getting much better all the time. You have options in it that will help with these sort of problems. You wont second guess getting once you have it! I have messed with most of the programs out their and this is one of the best! The only time i will be using Quickload any more is for doing pressure or wildcat tests...

 

[AJ172SBCT]

Any idea if this "shooter" program is or will be available for us blackberry users. There are programs for Android, Iphone, Itouch etc. but not much out there for Blackberry.
I feel left out

Thanks
Jacques

 

[blawton]

Any idea if this "shooter" program is or will be available for us blackberry users. There are programs for Android, Iphone, Itouch etc. but not much out there for Blackberry.
I feel left out

Thanks
Jacques

Sorry to say this but it doesnt look for the windows based os's. They change to much to write a really good program for them. The android having open source software has way more advantages and much easier to get stuff done on.

I did notice that their was a student in a school of trade for guns and was gonna write up a program for the blackberry but i doubt it will be done soon. The thread about it is over on the hide in the range report exterior ballistics section if you want to keep track of his progress.

 

[AJ172SBCT]

Thank you for responding, much appreciated.
I'll check the hide.

Jacques

 

[js223]

Have you verified the true movement your scope makes per click at short range? They may not move exactly the indicated value (1/4MOA or whatever) and that will become more critical the farther out you go. Another question, at JBM are you using the 'Litz' value in the library? Those use actual measured BCs if they say 'Litz' next to them.

 

[Benjerman08]

Yes, I have verified at close range. Not per click, but at 100 yards I am up 11" instead of 10" with 10 moa raise on turrets. Tried changing to the litz b.c. on JBM, but it only made about .1 moa change (dtac 115 pointed). Gun and scope (nightforce) work and shoot great. Just looking to make the program and gun in sync.

 

[6BRonwheels]

Hi,
Are you entering the correct scope height? It does not take much of an error on the scope height to mes things up.
Good Luck.
Jack

 

[js223]

To be in sync with the program, you must know the true elevation changes of your scope.
If you are up 11" at 100 yards with 10MOA of elevation then you are actually getting a little more than spec for your clicks. Should be 10.47" for 10MOA if you're actually at 100 yards. Seems you are getting an extra half minute with your 10MOA adjustment. If your scope is 1/8MOA adjustment this would equate to .131MOA per click average, if it's 1/4MOA it would be .262MOA per click average. These figures would only be valid if your 11" was an actual 100 yards, if it's 95 or 105 for example they'd need to be recalculated.
The scope height question brings up the point that good data will give a good calculation. If there's an error in the input then of course the output won't be correct.

 

[Benjerman08]

scope height is exactley 2". I noticed a little more height with the new pointed dtac. Seems to shoot a little flatter even though the proposed b.c. is about the same. Thanks.