|
|
Joined: Nov 2006
Posts: 5,796
Campfire Tracker
|
Campfire Tracker
Joined: Nov 2006
Posts: 5,796 |
Confident Long Range shooters usually shoot high BC 250-300 grain bullets in .338 caliber, which aren't so affected by wind.
Not so Confident Long Range shooters usually shoot lighter pills in the .308 caliber which are affected by wind.
Bold statements but I stand by them.
It is better to be judged by 12 than to be carried by 6.
|
|
|
|
|
Joined: Jul 2009
Posts: 14,076
Campfire Outfitter
|
|
Campfire Outfitter
Joined: Jul 2009
Posts: 14,076 |
Using the data above 3800fps with the AB and 3700 with the berger here is what you get from JBM real world results may vary slightly 110grn AB Wind Speed Full Value Inches of drift @500yds 10mph 14.6" 2.8moa 15mph 22" 4.2moa 20mph 29.3" 5.6moa 30mph 43.9" 8.4moa Wind Speed Full Value Inches of drift  1000 10mph 71" 6.8moa 15mph 107" 10.2moa 20mph 142.7" 13.6moa 30mph 214" 20.4moa 115grn Berger Wind Speed Full Value Inches of drift @500yds 10mph 12.1" 2.3moa 15mph 18.1" 3.5moa 20mph 24.2" 4.6moa 30mph 36.2" 6.9moa Wind Speed Full Value Inches of drift 1000 10mph 58" 5.6moa 15mph 88.1" 8.4moa 20mph 117.5" 11.2moa 30mph 176.2" 16.8moa So at 500 yards there is less than 7" difference in wind drift up to a 30mph full value wind. You can also see that if you miss your wind reading by 5mph you are screwed with either one. If you get your wind reading correct then all is right with the world. So the answer to your question does BC matter hell yes it does. Only you can decide if it matters enough for you to use a bullet that you do not really like or trust so that you can have that extra margin of error.
|
|
|
|
|
Joined: Sep 2001
Posts: 19,113 Likes: 8
Campfire Ranger
|
|
Campfire Ranger
Joined: Sep 2001
Posts: 19,113 Likes: 8 |
Within the framework of the 308 Win, it can make quite a difference in drift, retained energy, and drop. 168gr FGMM 2600 fps:
Tabular trajectory data at Non-Std. Atmosphere
Gunsite altitude : 4500 ft.
Air density : 0.066899 lb./ft�
-------------------------------------------------------------------------------------
Gun / Ammunition : 308 Win
Bullet : .308, 168, Sierra HPBT MK 2200
Bullet weight : 168 grains or 10.89 Grams
Muzzle velocity : 2600 fps
Crosswind speed : 10 Mph
Ballistic Coefficient(s) (G1):
C1=0.454@V>2600 fps;
C2=0.439@V>2100 fps;
C3=0.417@V>1600 fps;
C4=0.398@V>0 fps;
Range Velo Time of Energy Path Deflection Total Sight correction Target
city flight to at crosswind drop for setting new lead
LOS of 10.0 Mph zero range 33 fps
-------------------------------------------------------------------------------------
�Yards fps s ft.lbs. in. in. MOA in. Clicks MOA yds �
-------------------------------------------------------------------------------------
| 0 2600 0.0000 2521 -2.0 0.0 ----- 0.0 ------ ----- 0.00
M 87 2451 0.1031 2241 +0.1 0.5 0.52 2.0 -0.2 -0.06 1.13
X 100 2429 0.1189 2201 0.0 0.6 0.58 2.7 0.0 0.00 1.30
P 187 2284 0.2294 1946 -3.0 2.4 1.23 9.7 +6.2 +1.55 2.51
| 200 2263 0.2466 1910 -3.9 2.8 1.33 11.2 +7.5 +1.87 2.70
| 400 1945 0.5318 1411 -33.0 12.4 2.95 49.7 +31.6 +7.90 5.82
| 600 1648 0.8690 1013 -100.0 31.1 4.95 126.0 +63.7 +15.93 9.50
| 800 1381 1.2657 712 -218.4 60.3 7.20 253.7 +104.4 +26.09 13.84
| 1000 1170 1.7395 511 -413.3 103.1 9.84 457.9 +158.0 +39.49 19.02
208 AMax handload, 2600 fps:
Tabular trajectory data at Non-Std. Atmosphere
Gunsite altitude : 4500 ft.
Air density : 0.066899 lb./ft�
-------------------------------------------------------------------------------------
Gun / Ammunition : 308 Win
Bullet : .308, 208, Hornady A-MAX 30712
Bullet weight : 208 grains or 13.48 Grams
Muzzle velocity : 2600 fps
Crosswind speed : 10 Mph
Ballistic Coefficient(s) (G1):
C1=0.648@V>0 fps;
-------------------------------------------------------------------------------------
Range Velo Time of Energy Path Deflection Total Sight correction Target
city flight to at crosswind drop for setting new lead
LOS of 10.0 Mph zero range 33 fps
-------------------------------------------------------------------------------------
�Yards fps s ft.lbs. in. in. MOA in. Clicks MOA yds �
-------------------------------------------------------------------------------------
| 0 2600 0.0000 3122 -2.0 0.0 ----- 0.0 ------ ----- 0.00
M 87 2498 0.1024 2881 +0.1 0.4 0.39 2.0 -0.2 -0.05 1.12
X 100 2483 0.1180 2846 0.0 0.5 0.44 2.6 0.0 0.00 1.29
P 191 2378 0.2293 2612 -3.0 1.6 0.79 9.9 +6.0 +1.50 2.51
| 200 2368 0.2406 2590 -3.5 1.7 0.83 10.8 +6.8 +1.71 2.63
| 400 2148 0.5075 2132 -30.1 8.1 1.93 46.7 +28.9 +7.21 5.55
| 600 1940 0.7996 1739 -86.4 18.9 3.01 112.2 +55.1 +13.77 8.74
| 800 1745 1.1264 1407 -180.2 35.8 4.27 215.4 +86.1 +21.54 12.32
| 1000 1566 1.4927 1133 -321.6 59.6 5.69 366.0 +122.9 +30.73 16.32
|
|
|
|
|
Joined: May 2003
Posts: 111
Campfire Member
|
|
Campfire Member
Joined: May 2003
Posts: 111 |
Confident Long Range shooters usually shoot high BC 250-300 grain bullets in .338 caliber, which aren't so affected by wind.
Not so Confident Long Range shooters usually shoot lighter pills in the .308 caliber which are affected by wind.
Bold statements but I stand by them. Huh????? how does this make any sense???? You saying guys that shoot 308's and 6.5's aren't confident??? I'm sorry but those statements make absolutly no sense to me.. Tell all the guys shooting the 6.5x284 that are winning matches and see what they say.. Stand by them if you will but cmon really??? how does me shooting a 338 make me more confident then shooting a 308?? if your shooting distance no matter what caliber your shooting you have confidence in what that caliber will do.. i will say the 338's will buck the wind better but it wont make me more confident in what im shooting....
Amax his ass!!
|
|
|
|
|
Joined: Nov 2006
Posts: 5,796
Campfire Tracker
|
|
Campfire Tracker
Joined: Nov 2006
Posts: 5,796 |
i will say the 338's will buck the wind better but it wont make me more confident in what im shooting.... [/quote]
I shoot 6.5 x 284, and .308 and a 338/378 all at the same distances - with help of 2 buds. So after a few years of looking at what the wind does to the lighter pills, I can confidently say that if I want to be in the kill zone of an elk at 600-700 yds on a windy day, I won't even consider the other two.
It is better to be judged by 12 than to be carried by 6.
|
|
|
|
|
Joined: Sep 2004
Posts: 1,120
Campfire Regular
|
|
Campfire Regular
Joined: Sep 2004
Posts: 1,120 |
Don'
t know if this helps - BUT - I have made several one shot, DOTS (dead on the spot) kills on large deer at extended ranges (In excess of 400 yards), in front of reliabe witnesse. All were taken from a SOLID rested position, and in all cases was using a 235 grain, .375 Speer bullet in a .375 H&H that I shoot almost exclusively - and FREQUENTLY. I know what that bullet will do in that gun and have never looked at the BC.
Now I am going to look up the BC of the 300 grain Sirerra . 338 bullet and see what I can do with even more knowledge!
Terry
|
|
|
|
|
Joined: Sep 2006
Posts: 23,660 Likes: 1
Campfire Ranger
|
|
Campfire Ranger
Joined: Sep 2006
Posts: 23,660 Likes: 1 |
Her ya go...........the blue highlighted label "Trajectory" is the one to start with. You can plug in your BC's, wind speed, range. etc. & play what if's to your heart's content........all the answers to your questions are there in black & white. JBM Ballistics MM
|
|
|
|
|
Joined: May 2003
Posts: 111
Campfire Member
|
|
Campfire Member
Joined: May 2003
Posts: 111 |
ok let me throw this at ya.. I am in no way trying to dispute how well the 338 will buck the wind as it should and does very well.. But compared to lets say a fast 6.5 say the 6.5x300 weatherby AI which i know for a fact that it will drive the 142smk @ 3500fps as i own 2 of them... compair that to the 338/378 with the 300gr smk at 2800fps.. Now with those speeds compair a 10mph wind and the 6.5 will buck the wind just as good as the 338/378.. the 6.5 will also get it there alot flatter then 338 this will hold true clean out to about 1200yds after that the 338 will take over but only in wind drift the 6.5 is still flatter.. run those numbers through jbm and compair.. now the 6.5x284 at 3000 with the 142's wont buck the wind know where near as good but its not that bad either... So all in all it depends on what it is your shooting.
Last edited by Brock; 04/30/10.
Amax his ass!!
|
|
|
|
|
Joined: Nov 2006
Posts: 5,796
Campfire Tracker
|
|
Campfire Tracker
Joined: Nov 2006
Posts: 5,796 |
Heavier bullets are deflected less by the broadside winds. It's no mystery. How much do you think a canon ball will deflect in 700 yards going the same speed all things equal?
It is better to be judged by 12 than to be carried by 6.
|
|
|
|
|
Joined: May 2003
Posts: 111
Campfire Member
|
|
Campfire Member
Joined: May 2003
Posts: 111 |
You missed my point.. which is light bullets can do it just as well...
338 300smk @ 2800fps 700yds 23.7" drift 3.2moa @ 10MPH winds
6.5 142smk @ 3500fps 700yds 23.5" drift 3.2moa @ 10MPH winds
in this example both are equal... and it pretty much remains equal up to about 1200yds..
Last edited by Brock; 04/30/10.
Amax his ass!!
|
|
|
|
|
Joined: Feb 2007
Posts: 1,538
Campfire Regular
|
|
Campfire Regular
Joined: Feb 2007
Posts: 1,538 |
Brock, send the same bullet in .338 caliber to the speed of the 6.5 you referenced and see which one does better.
Send a 7mm 180g Berger at the 3500fps (per your reference) and see which one wins.
Just because you pick and choose your "better", doesnt mean that BC is not king.
|
|
|
|
|
Joined: May 2003
Posts: 111
Campfire Member
|
|
Campfire Member
Joined: May 2003
Posts: 111 |
Yes I would agree with you on that.. But just because you shoot a big heavy bullet doesnt make you any more confident then someone shooting a lighter bullet.. Like I said originaly I wasnt disputing the bucking abilities of the 338.. i was saying that in some instances they are equal...
Amax his ass!!
|
|
|
|
|
Joined: Feb 2007
Posts: 1,538
Campfire Regular
|
|
Campfire Regular
Joined: Feb 2007
Posts: 1,538 |
Cherry picking always looks better.
|
|
|
|
|
Joined: Apr 2010
Posts: 66
Campfire Greenhorn
|
|
OP
Campfire Greenhorn
Joined: Apr 2010
Posts: 66 |
I chose the bc for my 257 stw bullets because 1. I shoot that gun alot and 2 both bullets were at the top of each websites page, didnt have to scroll down. I often wonder what it will do at long range. 450 yards on elk and I am still holding on hair. I will carry that rifle off any mountain anywhere. I will never shoot a thousand yards at an elk and will never shoot 500 in a 30mph wind. No matter what their are too many veriables for me to take the shot. 15 inches of drift compared to 20 doesnt matter cause I wont shoot it in a wind like that. Now when I got curious about shooting distance I had a rifle built for it. Trued remington 700 action 28 inch pacnor heavy barrel 300 win mag full length glass bedded timney trigger 6.5x20 leupold vx3 with leupolds bullet drop turrets matched to my 200 gr accubonds at 3094 fps. This gun is now for sale. I always figured Long Range Hunting was a controvertial subject and that the guys who knew how to do it would stick together better than any other type of hunters. The skill that goes into making these shots is unreal. The firearms themselves are unbelievable. All I was really trying to find out was if .020 worth of bc would be a deciding factor on which bullet to buy. I will not shoot competetively so I dont care if you will beat me in a 1000 yard competition. All I kept hearing was that I am gonna miss in the wind and lose in 1000 yard shoots. And now that I know that, because my rifle isnt a 338 shooting a match bullet, I wont have the confidence ability or equipment to kill anything at any distance. So again rifle is for sale. Any offers? Ill stick with my stw and what I know. At 450- 500 yards hold on hair and keep filling tags.
Last edited by stwfanatic; 04/30/10.
|
|
|
|
|
Joined: Nov 2006
Posts: 5,796
Campfire Tracker
|
|
Campfire Tracker
Joined: Nov 2006
Posts: 5,796 |
Right on. Sounds like you have a winning combo there. Where i hunt it is windy (more then 10mph) over 200 days per year on average and I think along the lower states such as Montana it is even worst. So this puts us in a aprox 63% chance of hunting in wind. If you can hunt the windy days while the others sit in camp your odds are better than Joe Plumber who hunts on windless days.
The only reason I shoot at long range targets is to practise, practise, not to win competitions. It consumes much of my free time in the summer. Of all the calibers I own the .338 is the best long range rifle in my Harem.(shooting the HPBT 300 grain Sierras.)It will hit a basketball size target at 860 yds pretty consistently even on windy days. I cheat though and compensate (turrets)if the wind starts pushing me off target.
Never shot big game at those distances yet but my confidence is building year by year. Some fellas on this forum can easily hit targets like that at twice and even 3 times that distance. Whether I would drop the hammer on something that far away still ????? Unsure, worry about wounding and having to chase it around. I'd probably try to get closer if I could. Have agood day and by the way sounds like you have a great rifle there.
It is better to be judged by 12 than to be carried by 6.
|
|
|
|
|
Joined: Apr 2005
Posts: 30,990 Likes: 7
Campfire 'Bwana
|
Campfire 'Bwana
Joined: Apr 2005
Posts: 30,990 Likes: 7 |
Yes I would agree with you on that.. But just because you shoot a big heavy bullet doesnt make you any more confident then someone shooting a lighter bullet.. Like I said originaly I wasnt disputing the bucking abilities of the 338.. i was saying that in some instances they are equal... The heavier bullet with the larger diameter is always king when the bullets meet the meat at distance. The longer the distance the more the bigger bullets advantage
I got banned on another web site for a debate that happened on this site. That's a first
|
|
|
|
|
Joined: May 2003
Posts: 111
Campfire Member
|
|
Campfire Member
Joined: May 2003
Posts: 111 |
either way dead is dead...
Amax his ass!!
|
|
|
|
|
Joined: Feb 2007
Posts: 1,538
Campfire Regular
|
|
Campfire Regular
Joined: Feb 2007
Posts: 1,538 |
Brock, are you seriously arguing that a 142g SMK is comparable to 250/300g SMK in 338 for long range hunting????
|
|
|
|
|
Joined: Apr 2005
Posts: 30,990 Likes: 7
Campfire 'Bwana
|
|
Campfire 'Bwana
Joined: Apr 2005
Posts: 30,990 Likes: 7 |
The amount of jucie that a 140 grain 6.5 has left a 1000 yards is not even in the same ball park as is the 300 grain 338 bullet and the BC of .768 is another trump card. What kind of a barrel burner are you going to launch those 6.5's to get 3500 FPS? You missed my point.. which is light bullets can do it just as well...
338 300smk @ 2800fps 700yds 23.7" drift 3.2moa @ 10MPH winds
6.5 142smk @ 3500fps 700yds 23.5" drift 3.2moa @ 10MPH winds
in this example both are equal... and it pretty much remains equal up to about 1200yds.. Dam sure arn't equal when the bullet meets the meat
Last edited by jwp475; 05/01/10.
I got banned on another web site for a debate that happened on this site. That's a first
|
|
|
|
|
Joined: Apr 2005
Posts: 30,990 Likes: 7
Campfire 'Bwana
|
|
Campfire 'Bwana
Joined: Apr 2005
Posts: 30,990 Likes: 7 |
3100 FPS is a more reasonable speed for the 142 SMK and at 1000 yards in a 90 dergree 10 MPH wind the 142 SMK needs 6 MOA and the 300 SMK at 2800 FPS needs only 5 MAO of correction
The difference in the way the 2 hit game at the range is the difference between daylight and dark
I got banned on another web site for a debate that happened on this site. That's a first
|
|
|
|
|
596 members (12344mag, 007FJ, 10gaugemag, 10gaugeman, 160user, 61 invisible),
1,978
guests, and
1,300
robots. |
|
Key:
Admin,
Global Mod,
Mod
|
|
|
Forums81
Topics1,194,184
Posts18,523,803
Members74,030
| |
Most Online11,491
Jul 7th, 2023
|
|
|
|
