Forums › Forums › General Discussion › Requesting ballistic data for .308 loads fired from a T3
-
Requesting ballistic data for .308 loads fired from a T3
Posted by jeffbarnett513 on January 22, 2015 at 10:24 pmTrying to do some ballistic homework before I hit the range. Does anyone have detailed data on muzzle velocity and/or drop for Federal Gold Medal Match .308 as fired from a Tikka T3 with a standard 570mm (22.4″) long barrel? Any other loads with data available?
Ericbc7 replied 9 years, 2 months ago 4 Members · 5 Replies -
5 Replies
-
21 Bullseyes
Sorry bud, you need to buy a chronograph. We cannot do load development without buying one, I use a prochrono and its ok, for a $100 or so
-
1 Bullseye
Take what ever velocity you find on the net and subtract 25fps for every inch of barrel you don't have. The majority of the vendors test their velocity with a 24″ barrel. I find that to be pretty accurate somewhat when shooting stock ammo. For example… 16″ carbine shooting 308 168gr amax at 2460fps vs my 24″ shooting the same ammo, gets 2660fps. That's 25fps per inch of lost fps. Those were handloads and are pretty consistent. Cheers
-
21 Bullseyes
I apologize for my short answer earlier, yes you can do load development without a chronograph, but it is hard. What I would do is load up several test rounds of various powder charge and look for pressure signs. then pick one that seems safe and start shooting. you will need at least 300 yd range and preferably 500 or more. Carefully map the drop of the bullet using a 100 yd zero for various distances and plug your data into a ballistic calculator. This will give you a decent estimate of the average muzzle velocity but will give you no info on extreme spread (ES) or Standard Deviation (SD). The ES number will give you the better load density evaluation usually but without a chrono you are looking at a LOT of shooting. Good luck friend.
-
1 Bullseye
Learn the OCW method and forget about everything else.
-
21 Bullseyes
Dan Newberry's method is a decent option but, Eric Cortina has refined it a bit and his is the method I prefer. No round robin nonsense, and use a chronograph. check out his post on Accurateshooter.com long range load development at 100 yrd (or something named close) and look at the protocol. The goal is to get the best load range for the least cost in components.
Log in to reply.