Heat Report post Posted August 4, 2010 I just bought a new scope. It's a Leupold VX3 4.5-14x40 CDS. I would like to know how to determine ballistics for my rifle so I can get Leupold to make the most effective cap for my turret. My rifle is a browning a bolt .270 and has a 22" barrel. The factory load I like lists it's ballistics using a 24" barrel. Is there a way to determine my fps at the muzzle without using a chrono? Do you think the 2" inches of barrel makes a significant difference. I would guess that it does. Do you think Leupold has enough info as it is to figure out what I need, for example what are the chances they have already built a cap for a scope on the same rifle of the same caliber shooting the same load? Any thoughts along these lines would be great. I am really excited about the idea of being able to shoot out to 600 yards with a dead hold after a few clicks of the turret based on the known distance. I think that is a MUCH better option than using a plain scope like I had with a basic reticle, and for me probably better than using a ballistic reticle. Thanks in advance, Nick Share this post Link to post Share on other sites
DesertBull Report post Posted August 4, 2010 I would not trust the factory data, even if your barrel was 24". You can buy a Chrony F1 on Ebay for ~$80. It's cheaper than giving Leupold the wrong data and having a worthless turret. Share this post Link to post Share on other sites
Red Rabbit Report post Posted August 4, 2010 Nick, I would not use the factory ammo ballistc numbers or reloading manual numbers. Find someone with a good chronograph. I am suprised that they do not ask for scope height above bore (at least I did not see it on the Leupold site). Share this post Link to post Share on other sites
Coues Sniper Report post Posted August 4, 2010 I did the custom turret deal with Leupold, and it wasn't accurate. The dial was consistently low starting at about 300 yards. To be on at 700 I had to dial to 840. I put the data I gave them into a program and it agreed with what i was actually seeing in the field. Not sure how, but they messed up. I'm sending it back and having them put on M1 turrets which is what I should have done in the first place. Share this post Link to post Share on other sites
Heat Report post Posted August 5, 2010 I talked to a CW.com member to see about borrowing one (matthewp45) and we're going to get 'er figured out. Thanks for the input guys! And thank you Matt! Nick Share this post Link to post Share on other sites