I just dug out my 338 ultra data with a 300 grain Berger with a BC of .818 @2830 it's calling for 16.1 moa at 800 yards with a 100 yard zero. I am not saying yours did not impact at 800 with 16 most because you were there and it did, I am just trying to understand why it did.
338 RUM 300 gr AB Field Test
- Thread starter JD338
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bullet
Handloader
- Dec 26, 2007
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Great shooting and I see you had a lot of fun doing it. Way to go JD :mrgreen:
nvbroncrider
Handloader
- Aug 20, 2011
- 3,085
- 4
usmc 89":3gfo6gv0 said:
Yes there are a lot of varibles I assumed a lot of stuff on those numbers one of the most important is if the target was on the same elevation as his shooting platform if it was 2 or 3 feet lower that would easily account for the difference. Plus elevation where he was shooting at. There are a whole lot more numbers than I had to work with but he was also using a 200 yd zero. That's another important part of it. He was also 2740 MV. But all in all that's impressive!
Greg Nolan
Handloader
- Nov 25, 2004
- 2,143
- 18
Jim
That's impressive long range work. The twist must stabilize the big 300 pretty good. Life just got tougher being an elk.
That's impressive long range work. The twist must stabilize the big 300 pretty good. Life just got tougher being an elk.
His zero would be taken into account via the ballistic program. Just curious why there is a 2 moa discrepancy at 800 that is pretty large at that distance. There feet of elevation in the platform will have minimal if any affect on the trajectory at that distance, I don't think it would be more than a degree if it was. Not denying the rifle and shooter are working extremely well just wondering why the projection and impact are 2moa off at 800. Tweeking the BC will only compound the problem in the deflection department. Jdj was everything accounted for such as sight height muzzle velocity and altitude density? Did you run it through the jbm ballistic calculator with the g1 and g7 values.? litz should have the 300 AccuBond listed on there bullet list click on it and then run your numbers. the jbm system has been very accurate even with a .223 out to 1k.
big rifle man
Handloader
- Dec 21, 2005
- 850
- 0
Jim, great long range shooting. If I'm not mistaken (haven't looked at the charts yet) Past 350 yards the .338RUM is doing better than the .300RUM with a 200 grain bullet. The .338 really comes into its own at extended range. Theres a reason the military uses a .338 for long range sniping purposes.
.300winmag
Handloader
- Oct 17, 2011
- 660
- 1
JD338,
would you mind sharing what altitude and temp you were shooting at the 800 yard target?
would you mind sharing what altitude and temp you were shooting at the 800 yard target?
- Thread starter
- #29
- Nov 4, 2004
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.300winmag":2l9h6c0g said:
300WM
Elevation is 1500'
Temp 80* F
Jeff opened my eyes with the Density Altitude Calculator as it would have been equalivant to 4200'.
I also need to verify my 200 yd zero. When I plug in a 250 yd zero, everything matches up! It would also explain why I hit that doe so much higher than I aimed. A 250 yd zero puts the bullet 3.0" high at 100 yds.
JD338
.300winmag
Handloader
- Oct 17, 2011
- 660
- 1
Your density altitude will make a huge difference, as well as your zero range. I ran some numbers and calculated a G7 BC on the 300gr. AB of .3581 based off the dimensions of the bullet. This BC is averaged from mach 1.2-mach 3. I did it the same way I calculate the BC's for my own long range rifles. I use JBM's drag calculator and it has been extremely accurate for me. I inputed the data you provided into my ballistics program and it gave me 17.25MOA, a minute higher than what your actually needed.
It appears on the gong that it is about 3 inches low of center, is this correct? if so, it would require +1 click on a quarter minute scope to bring it center from your 16.25 MOA zero. I then ran the numbers in a ballistics truing program I have by inputting your data. When I used a G1 BC of 0.720 at 800 yards with the atmospherics you gave me and a 3 inch low impact with 16.25MOA on the dial, it suggests a corrected MV of 2791 MOA to bring your drop data into line with your results. When I run it with my calculated G7 BC it needs a corrected MV of 2,795fps to bring your drop data into line with your results.
What I would suggest is checking your zero first! If you find you were actually zeroed at 250 and that makes everything line up then that made everything a lot easier! If you were indeed zeroed at 200 yards I would start by adjusting your ballistics programs MV to between 2791-2795fps and use your G1 BC of 0.720 (I assume that is what you're using) or a G7 BC of 0.3581. After that, go out and shoot multiple distances if you can. Say shoot a group at 600, 800 and 1000 yards; the farther the better. What you are looking for in these groups is where the group center is vertically from your aim point. With this 'corrected' MV you should be pretty close. If you measure the group center on all three targets and the center is lets say 0.25 MOA high on all the targets, then bring the dial back to zero, then bring it 0.25MOA down and use your allen wrenches to make the dial read zero at this point. This will bring your POI a half in lower at 200 yards (not a big deal for hunting) and will bring your impacts at longer ranges more on. This is one thing I do with all of my long range rifles and it makes a world of difference in making long range hits. I am trusting that the ranges you shot are also measured within a few yards.
That is some fine shooting at 800 for sure! very impressive! Long range shooting is a blast but it can be frustrating getting all the bugs worked out; once you do however, it is a very satisfying feeling! I hope this may help.
Cheers
It appears on the gong that it is about 3 inches low of center, is this correct? if so, it would require +1 click on a quarter minute scope to bring it center from your 16.25 MOA zero. I then ran the numbers in a ballistics truing program I have by inputting your data. When I used a G1 BC of 0.720 at 800 yards with the atmospherics you gave me and a 3 inch low impact with 16.25MOA on the dial, it suggests a corrected MV of 2791 MOA to bring your drop data into line with your results. When I run it with my calculated G7 BC it needs a corrected MV of 2,795fps to bring your drop data into line with your results.
What I would suggest is checking your zero first! If you find you were actually zeroed at 250 and that makes everything line up then that made everything a lot easier! If you were indeed zeroed at 200 yards I would start by adjusting your ballistics programs MV to between 2791-2795fps and use your G1 BC of 0.720 (I assume that is what you're using) or a G7 BC of 0.3581. After that, go out and shoot multiple distances if you can. Say shoot a group at 600, 800 and 1000 yards; the farther the better. What you are looking for in these groups is where the group center is vertically from your aim point. With this 'corrected' MV you should be pretty close. If you measure the group center on all three targets and the center is lets say 0.25 MOA high on all the targets, then bring the dial back to zero, then bring it 0.25MOA down and use your allen wrenches to make the dial read zero at this point. This will bring your POI a half in lower at 200 yards (not a big deal for hunting) and will bring your impacts at longer ranges more on. This is one thing I do with all of my long range rifles and it makes a world of difference in making long range hits. I am trusting that the ranges you shot are also measured within a few yards.
That is some fine shooting at 800 for sure! very impressive! Long range shooting is a blast but it can be frustrating getting all the bugs worked out; once you do however, it is a very satisfying feeling! I hope this may help.
Cheers
- Thread starter
- #31
- Nov 4, 2004
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300WM,
Thank you for digging into it for me. I appreciate it. :grin:
JD338
Thank you for digging into it for me. I appreciate it. :grin:
JD338
.300winmag
Handloader
- Oct 17, 2011
- 660
- 1
Not a problem JD, this is kind of stuff is right up my alley. My girlfriend says I have a problem and I'm obsessed with bullets and external ballistics. I tell her she's obsessed with shoes...that's usually when I get the eye roll and "It's not the same!" before she wanders off. :mrgreen:
remingtonman_25_06
Handloader
- Nov 17, 2005
- 2,806
- 403
Looks like ya had good time Jim! Glad you could finally get out to a range where you can stretch her a bit!
Great shooting with the 338 RUM and 300g AB.
Nice work on that doe too!! Pretty sure she felt like getting hit by a mack truck
Great shooting with the 338 RUM and 300g AB.
Nice work on that doe too!! Pretty sure she felt like getting hit by a mack truck
6mm Remington
Ammo Smith
- Feb 27, 2006
- 5,278
- 708
Very nice shooting there Jim!! No wonder she dropped so quickly. She should be good eating as well. Tenderloins in the BBQ.
David
David
JD338":p01g9hk3 said:
I think I stumbled upon the solution to my "problem"...
I picked up that Weatherby Vangard 257 Roy last year and I love it, but would love a longer barrel. I have a CM #4 .25 cal blank in my basement and a NICE commercial mauser action/BEAUTIFUL french walnut stock to drop it into.
That'd free up the Vangard action as a donor for a 340 Bee or 338 RUM... I also have a Savage 110 action that, with $150 in mods, could be made to work with the Bee... as-is it could work nicely as a 338-375 Ruger with LOTS of mag space to seat those sleek missiles WAY out there...
Suggestions y'all?
Oldtrader3
Ammo Smith
- Nov 6, 2009
- 8,406
- 6
I have a .340 and I really am fond of it, but! If I was serious about longer range (>600 yards) shooting, I would invest in a .338 Lapua. The reason being, the Lapua cases and their precision dimensions, hardness, case capacity and construction. The Norma and Nosler cases that I use in my .340 are great cases for accuracy at the hunting level which I need to 400 yards. However, for serious work at longer range the superlative Lapua case is the way to go for precision and muzzle velocity with large and heavier bullets.
- Thread starter
- #39
- Nov 4, 2004
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I went back out to the farm and was able to confirm the ballistics program at 800 yds. We had a big storm coming in and the deer were moving early so I did not spend much time on the 800 yd target.
I set up on the edge of a bean field and didn't wait too long for deer to show up. I had a doe come into the field. I put the cross hairs tight behind the shoulder and the 338 RUM roared, sending the 300 gr AB across the beans and into the chest of the doe standing broadside at 200 yds. The deer took a couple steps and crashed to the ground.
Here is the entrance wound.
Here is the exit. The big 300 gr AB opened up nicely on this average size doe.
Here are a couple more pictures back in the barn.
JD338
I set up on the edge of a bean field and didn't wait too long for deer to show up. I had a doe come into the field. I put the cross hairs tight behind the shoulder and the 338 RUM roared, sending the 300 gr AB across the beans and into the chest of the doe standing broadside at 200 yds. The deer took a couple steps and crashed to the ground.
Here is the entrance wound.
Here is the exit. The big 300 gr AB opened up nicely on this average size doe.
Here are a couple more pictures back in the barn.
JD338
DrMike
Ballistician
- Nov 8, 2006
- 37,543
- 6,619
That big 300 grain pill definitely left a gaping hold in her shoulder, Jim. Good show.
