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.308 ballistics/trajectory???
#1
I'm sooooooooooo new to shooting my Rem 700 in .308 at distances past 100 yards.

I'm curious as I'm using a 100 yard zero because that's the range I shoot at 95% of the time.

My rifle is a REM 700SPS tactical with a 20 in barrel. I shoot Federal GMM SMK 168gr listed at 2650fps at the muzzle.

Is there an easy method to figure out bullet drop/trajectory out to 800 yards?

Not even sure if I'm asking the question correctly.

Hoping Tomcat and/or Lycan will try to help answer this.
Certified NRA LE Handgun/Shotgun Instructor
Pa ACT235 Firearms Instructor
Speed is fine, accuracy is final.

U.S. Navy veteran
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#2
DaveM55;49501 Wrote:Is there an easy method to figure out bullet drop/trajectory out to 800 yards?

Not even sure if I'm asking the question correctly.

Hoping Tomcat and/or Lycan will try to help answer this.

Your question is very easily answered. All you need do is go to your favorite search engine and search for "ballistics calculators". You'll get a number of choices. Norma Ammunition has one of my favorites.

You'll need to know (or be able to aproximate) certain pieces of information such as velocity and the ballistic co-efficient of your bullet, but those aren't hard to determine.
Brick, proud to be a member of pa2a.org since Sep 2012.
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#3
Try this link
http://www.biggameinfo.com/index.aspx
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#4
DaveM55;49501 Wrote:I'm sooooooooooo new to shooting my Rem 700 in .308 at distances past 100 yards.

I'm curious as I'm using a 100 yard zero because that's the range I shoot at 95% of the time.

My rifle is a REM 700SPS tactical with a 20 in barrel. I shoot Federal GMM SMK 168gr listed at 2650fps at the muzzle.

Is there an easy method to figure out bullet drop/trajectory out to 800 yards?

Not even sure if I'm asking the question correctly.

Hoping Tomcat and/or Lycan will try to help answer this.

Howdy Dave. I knew my ears were burning for some reason, lol. There are some very easy methods that will get you in the ballpark of shooting out at longer ranges. Most those involve ballistic calculators. The good thing is that they're readily available for free, or at very low cost. Honestly, besides a ballistic calculator, you have to pull out an accompaniment to reloading manuals like the old timers did with ballistic tables, and that only go you in the neighborhood. The other alternative was to shoot out to distances and figure it out. The good thing is that if you put in the correct information in a ballistic calculator, they will get you really close and you don't have to waste ammo.

I'll be happy to run some numbers for you in some different ballistic calculators that I have, but I need a bit more info. You have to realize that these results may be a little bit off because the actual velocity from your rifle may be a little bit slower than what the factory numbers are. It would also help if you knew the elevation of the place you were shooting at, and something close to the temperature, humidity, and if possible barometric pressure. The more info we can accurately add into the program, the more accurate the results will be.

For the record, lots of people with smart phones like to use Strelok, since it's free. I personally don't have any experience with that particular program. I bought "Shooter" for $10 (I think), and I've been VERY pleased with the results. It also offers a truing function so that you can get adjusted numbers that actually match your dope. There's free ones online, and one of the best and most trusted is JBM. http://www.jbmballistics.com/ballistics/...tors.shtml If you need help using the program, we'll be happy to help you. The good thing is that there's ton of info available for the load that you're shooting. When possible, I would you the "Litz" BC's because those come from Bryan Litz from Berger bullets, and they actually use Doppler radar to get their numbers, and in my experience they're more accurate at longer ranges. I've also been really happy with the Berger program, it's free, cheap, and very small. For anyone interested in the program, just shoot me a PM and I can email you the program to share it. It was on Berger's website, but somehow it has disappeared. The nice thing about having a program downloaded is that you don't have to be able to jump online to use the program. This one also allows the option of printing out your results and attaching them to your rifle.

Oh, and keep in mind that not all ballistic calculators are created equal. Lots of times at closer ranges, they will come up with the same numbers. With others, when you start to stretch things out, the numbers that come back can be pretty different. Part of this is related to how the program compensates for different variables. Honestly, for long range shooting with the types of bullets that we use, the G7 BC usually gives more accurate results. Since G1 BC is so common, most of these programs have figured out ways to tweak their results to be pretty close to the G7 BC, but that's where it's all derived from. I hope this helps, and if this is confusing at all, please feel free to ask questions and we'll elaborate.
Tomcat088, proud to be a member of pa2a.org since Sep 2012.
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#5
I don't have a smart phone, don't really like them. It drives me nuts to see people on thier phones all day long. OK enough social commentary.

Any use Mildot Master?

I have started looking at a few ballistic calculators online. Shouldn't be too hard to figure it out.

Thanks TC088.
Certified NRA LE Handgun/Shotgun Instructor
Pa ACT235 Firearms Instructor
Speed is fine, accuracy is final.

U.S. Navy veteran
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#6
You need to buy a chronograph because those MV on the box of your ammo was probably shot from a 26" barrel.

JBM offers a good ballistics calculator and there are tons of others available on the net.

I know you said you dislike smart phones, but if you have an andriod phone get "shooter" it's worth the $9.99. There are other free ballistics apps, but shooter is the one I like using.

Having shooter is nice because it is portable and you can make corrections at the range. You aren't going to be able to make corrections with JBM or other programs unless you have a laptop/tablet with internet access in the field.
aubie515, proud to be a member of pa2a.org since Sep 2012.
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#7
DaveM55;49642 Wrote:I don't have a smart phone, don't really like them. It drives me nuts to see people on thier phones all day long. OK enough social commentary.

Any use Mildot Master?

I have started looking at a few ballistic calculators online. Shouldn't be too hard to figure it out.

Thanks TC088.

I use mildot master. It can get wet.
One must still have chaos in oneself to be able to give birth to a dancing star.
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