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View Full Version : My Elevation Dope Data. Back in the days.


Clever
09-28-2013, 5:41 PM
I was cleaning my safe today and found this in my old .308 Win data folder. Thought it would help our .308 Win Brothers. I used this data out to 1000 yards with Factory Loaded Rounds (Federal Gold Medal Match 168gr HPBT) out of a:
Remington 700 SPS Varmint .308 Win
Factory 26" Bull Barrel 1:12 Twist also shot 1:10
Badger FTE Muzzle Brake
Stock: H&S Precision off of a 700P short action (Torqued to 65 inch pounds)
Scope: Leupold Mark4 8.5X25X50mm Mil Dot 30mm Tube
Base: Leupold 20moa Picatinny Rail (Torque to 30 inch pounds)
Rings: Leupold 30mm Mark4 Medium Rings (Torque 20 inch pounds) Windage Screw (Torque between 35 to 40 inch pounds)
Trigger: Jewel set at 3lbs
GOOD LUCK..
http://i909.photobucket.com/albums/ac294/arsho13/ed8895be-7eac-4fb3-8eae-3d3c30c715ed.jpg (http://s909.photobucket.com/user/arsho13/media/ed8895be-7eac-4fb3-8eae-3d3c30c715ed.jpg.html)

Clever
09-28-2013, 6:20 PM
bump

postal
09-28-2013, 7:37 PM
Most people are using 175 smks now- or 155's if your gun can push them fast enough. Some people use the Amax rounds or lapua scenars, but I hear Amax is having accuracy/consistency issues lately- though I dont know if it's true....

A lot of people are moving to mil/mil scopes as well... so on both counts your data is outdated.

You also didnt give MV of that load through your rifle.

So... if someone shoots factory 168's out of a factory26" barrel, it would give them a decent idea what to expect... However, every rifle is different, and shoots a different velocity...

And few people still use the old 168's now.... so it isnt particularly usefull to most people.

Your chart also doesnt have wind hold or movers.

But thats a sweet lookin TRG in your sig line!

Now... its really easy to get a pretty accurate chart using the website "JBMballistics.com". Especially if you have access to a chronograph to punch in the actual MV. (you want the basic "trajectory" chart)

There are apps for smartphones that do similar, though I think JBM is probably better for a real chart, though the phone apps are handy in a pinch.

My chart from JBM is my bullet, at my MV, with MY scope height over the bore centerline... with MY ranges altitude... with a temperature I select... with 5 mph 90 deg crosswind (I specified) with a moving target of 5 mph (I specified)... and it spits it all out on one nice neat form from 100 to 1000 in 25 yard increments (I specified) and it shows it in inches and mils (I specified)

I have a second chart that shows 10 yd to 100 yd in 10 yd increments... Though I should replace it with a 10-100 with 5 yd increments.... that comes up sometimes in the matches I shoot- ultra close range- 10-25 yds and such....

(5 mph wind at 90 deg and 5mph mover at 90 deg is really easy to cut in half for 2.5 mph wind, double for 10, triple for 15 etc.... same with mover.... and you can cut it in half for a 45 deg wind etc also very easily.)

That program can be setup for whatever info you want- distances you want in increments you want, windage you want, mover you want, elevation, temp, humidity, etc... then outputs it in inches, moa, mils, yards, meters, fps, energy, marking crossing sound barrier, etc etc..

All free and easy to do. Mind boggling the first time you use it since there are so many variables to input... and it's VERY accurate- not perfect... but VERY close.. all data must be shot at actual distance to verify and correct, but it's CLOSE!!!

But that is a sweet TRG... Always liked those....

ar15barrels
09-28-2013, 11:57 PM
Factory Loaded Rounds (Federal Gold Medal Match 168gr HPBT)

http://i909.photobucket.com/albums/ac294/arsho13/ed8895be-7eac-4fb3-8eae-3d3c30c715ed.jpg (http://s909.photobucket.com/user/arsho13/media/ed8895be-7eac-4fb3-8eae-3d3c30c715ed.jpg.html)

You must shoot at high altitude.
At lower altitudes, we watch those 168's turning end over end as they go through the 900 or 1000yd targets and we usually pull the shooters off the line once they start lobbing them into the berm or when they can't keep them on the 72" square frames...

Clever
09-29-2013, 1:15 AM
Randall I achieved this 6 years ago, at Mojave. 13 people there 8 of us hit the 1K Target. Using 168gr Smk, my rifle had a 12 twist while others shot with a 10 twist. I don't shoot .308 anymore, my post is what I have achieved with what I had at the time. If it's not what works now a days then that's what it is. I Thank You for being a true Pro.

GJC
09-29-2013, 11:27 AM
Thank you for the info!

hambam105
09-29-2013, 10:09 PM
Aren’t .30 cal bullets traveling at sub sonic speeds@ 800 0r 900 yards just a little bit blury?

ar15barrels
09-29-2013, 10:45 PM
Randall I achieved this 6 years ago, at Mojave.

Ah ha, high altitude = thin air.
Try that stunt at Pendleton in the winter...

Spyder
09-30-2013, 6:39 AM
Pretty cool that you can look at the data and know he was at high altitude. Goes to show, that even with the enjoyable bickering, there's always something to learn! :D

Clever, thanks for the info. What are you shooting these days, since you said this was old info from your projects years ago? Give us updates!

milotrain
09-30-2013, 8:57 AM
Pendleton in the winter...

Like shooting through soup.

Clever
10-04-2013, 5:34 PM
Pretty cool that you can look at the data and know he was at high altitude. Goes to show, that even with the enjoyable bickering, there's always something to learn! :D

Clever, thanks for the info. What are you shooting these days, since you said this was old info from your projects years ago? Give us updates!

Sako TRG 42 338 Lapua Magnum