Originally Posted by freed0m man
Would I be teaching myself more about long range shooting if I were to build a AR platform .223 caliber rifle vs. going out and picking up a .308 or a hot 6.5mm caliber rifle?
Would I learn more about how atmospheric conditions effect the bullet by shooting a lighter bullet at longer ranges. I'm really wanting to learn more about the mechanics and mathematics behind shooting.
To be honest, you want to pick the caliber you want to shoot and shoot it. Each caliber has it's own little quirks when it comes to learning long range. If you were to get an AR10 built in a 243 or 260 you would be ahead in the game for long range. They offer some of the best bullets w/ high BC's that work well in competition. The AR15 variants, you would do well to go with the 223 w/ a tight twist shooting 75 to 80 grain bullets, or the 6.5 Grendal. There are a ton of wildcat calibers that would fit your specific needs, but these are the few you are going to find on the shelf ammo. IF you want to stick with a classic caliber than the .308 is the way to go. Lord knows how many competitions have been won with this caliber, but it has been surpassed.
Bolt guns are no slouches when it comes to tactical competitions either. They have set the standard. I would highly suggest the 243 Ackley Improved, 6XC, or the 260 AI. All will give you out standing performance. The 6.5x47 Lapua with 123 grain bullet would also do well. Here is a good article if you haven't read it already: Getting Started In Tactical Rifle Competition
Hope this helps.
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