billythekid Report post Posted November 24, 2015 howdy guys, im somewhat new to trying to reach out and dial in to go "long range." if you could help me out, with the various ballistic programs, i cant get anything to "match up" to what im actually shooting for dopes. im shooting a rem 700 30-06 with sierra 165gr that have a bc of .404. not sure on velocity, no chrono.... - at 300 yards, ive had a drop of 10.5". - at 530 yards, a dope of 11.5 moa brings elevation up to perfect - i havent gone further than that yet i cant get these 2 to correspond with any ballistic programs? any help or advise would be great! Share this post Link to post Share on other sites
WampusCat Report post Posted November 24, 2015 LOTS of variables here , but we can guess pretty close on your given case/bullet weight combo. Without knowing your barrel length I would venture to say you are in the 2750-2850 fps range. Your .404 is likely not exact either. Lots of manufacturers are very generous in this area. It's merely a great place to start. Use them together to get on target and the adjust one or the other in the program until the ballistic curve matches what your rifle is shooting with actual range data. The distance your scope is "zeroed" at will also affect your data. Make sure you are speaking the same language when comparing drops or corrections. @ 300yds your 10.5" will be close to 3.5 moa. 1 Share this post Link to post Share on other sites
lancetkenyon Report post Posted November 24, 2015 First, lets get some terminology straightened out. Sorry, not trying to be a jerk. "DOPE" = Data On Previous Engagements. Meaning what you have learned about your trajectory at various conditions. Figuring out your drop for YOUR rifle is done by exactly what you have been doing, shooting it, then adjusting a ballistics program to match what you have observed. Great start. Too many people think they can look at a program and go out and shoot 500-1000 yards. Most ballistics programs are set up to true your velocity, BC, etc. to make your load and drops more predictable. Sierra is pretty good about the BC, but you have to realize the BC is based on velocity, so when the bullet starts to slow, the BC changes along with it. Here are a few items that would really help with your data . Which Sierra 165 gr. you are shooting? Looks like it is probably the 165 SBT Game King? According to "Shooter", the 165 SBT Game King has an average BC of .416 per Bryan Litz. (.404 2400+fps, .409 1600-2400, .419 0-1600). Muzzle velocity? Without shooting through a chronograph to get you close, you really have to play with numbers to figure out your velocity. Shooting at various distances would help a lot with truing your ballistics program by inputting actual drops at known distances. But a chrono only gets you a starting point, you need to shoot and record drops to ensure a proper drop chart. Conditions you were shooting in? Conditions of initial zero? Varying conditions can play a big role in ballistics. Elevation, barometric pressure, temps, humidity, etc. Gun set-up? Scope height? Barrel twist? Zero yardage (or POI at 100)? I think WampusCat is close in his velocity range with doing some quick calculations. I think probably closer to the top end, but without a lot more info from you, it is nearly impossible to start making an educated guess. 5 Share this post Link to post Share on other sites
n2horns Report post Posted November 24, 2015 Agree with the above. Good info and advice. Also, don't over shoot and heat up the barrel. Clean barrel vs fouled barrel has variance. I foul a few shots before measuring. Not sure if you reload or not but factory ammo varies from maker to maker as well as your barrel may like one maker more than the other. Share this post Link to post Share on other sites
GreyGhost85 Report post Posted November 24, 2015 i would bet that you are dealing with a velocity issue. only way to true your velocity is shooting it at a lot of different ranges and writing down what you had to adjust you. once you get a good idea, mess around with your velocity in the app until your numbers line up. read through Lance's write up and follow what he says. He knows more about ballistics than most of us could hope to learn in a lifetime 1 Share this post Link to post Share on other sites
Big Browns Report post Posted November 24, 2015 What program are you using? If it has Velocity Validation you can get the program to match to 500 pretty easily. If not you will have to work out your numbers before you can figure out your true validation. I highly recommend you use "Shooter" app. It's one of the best. There are also a lot of YouTube video's regarding this subject. A few hours on YouTube will save you a lot of time and money in the field. Feel free to call me with any additional questions. Share this post Link to post Share on other sites
STOMP442 Report post Posted November 24, 2015 Forget the program and just write down what you need to actually dial to in order to hit your target as centered as possible. Next step is to practice and verify those numbers in varying conditions tape your chart to your rifle or scope or keep in your wallet or whatever you need to and shoot with the confidence of known actual data. Much better and much quicker than messing with an app while behind the rifle looking at a buck on the other side of the canyon. A little more info for you: Litz Tested BC Measurements. The G7 bc of the 165 Sierra Game King = .213 The G1 Average = .416 These numbers should help a little but you are also going to need correct altitude, temp and pressure inputs as well as a correct scope height for any ballistics program to even be close. 1 Share this post Link to post Share on other sites
cactusjack Report post Posted November 24, 2015 Lancetkenyon pretty much summed it up. Other then him calling you Grasshopper and telling you "when you can take the primer from his hand, you will be ready to leave." it has been covered. You might need to sand his deck or paint his fence. 2 Share this post Link to post Share on other sites
billythekid Report post Posted November 25, 2015 Awesome guys, and thanks! I came home to a bunch of great replies. So here is some more info.... - I do roll my own bullets - 50.5gr imr4320 - 165 sierra gamekings sbt's - scope is 1.5" above barrel - 24" barrel - zeroed at 100y - zero conditions, aprox 1300f and 70d You guys are great and I really appriciate the replies. I'm going to play around a bit more with the .416bc vs what I had. This weekend I'll try and get some more data from the field! Share this post Link to post Share on other sites
308Nut Report post Posted December 1, 2015 How did you determine there was 10.5" drop at 300 yards? Did you dial and convert to inches or did you aim dead on with your 100 yard zero and measure the drop? Share this post Link to post Share on other sites
billythekid Report post Posted December 1, 2015 At 300, I aimed dead on with my 100y zero. Share this post Link to post Share on other sites
