Long range bullet for 308win

[MontanaMarine]

I cannot tell a difference in the accuracy potential between the 210 Berger and 208 AMax in my rifle. They are both very solid sub-moa accurate, often grouping below .5 moa.

IMR 4831 might be a tad bulky to get the mosr out of the limited volume in a 308 case, but will be curious to hear your results.

I try to maximize volume by using Win brass, then only resizing the neck. At OAL 2.95" I can put 49.0 gr W760 in there without excess compression, 50gr leaves a mark on the bullet from the seater, and "grows" a bit overnight. Might not grow with uncoated bullets, but I'm using moly.

VV N550 and RL17 look like good powders for the 208/210 also, but I don't have any firsthand experience with them.

 

[MontanaMarine]

Here's a couple calcs at 4500' el. 175 Berger at 2750 fps, and 208 AMax at 2550

 Tabular trajectory data at Non-Std. Atmosphere
 Gunsite altitude : 4500 ft.
 Air density      : 0.064951 lb./ft³
-------------------------------------------------------------------------------------
 Gun / Ammunition : 308 Win
 Bullet           : .308, 175, Berger VLD
 Bullet weight    : 175 grains or 11.34 Grams
 Muzzle velocity  : 2750 fps
 Crosswind speed  : 10 Mph 
 Ballistic Coefficient(s) (G1): 
 C1=0.527@V>0 fps;


 Optimum trajectory information : 
 Optimum sight-in range (X) = 245 Yds. 
 with max. ordinate above LOS at range (M)= 139 Yds.
 and max. point blank range (P)= 286 Yds.
-------------------------------------------------------------------------------------
 Bullet path for firing up- or downhill! Angle of site/elevation 5 deg.
 Figures for velocity and energy relate to level firing.
 Sight-in clicks, 1 click = 1.0 cm/100 m or 0.394 in/100 m
 Height of sight above bore axis = 4.7 cm or 1.85 inch
 Gun is zeroed-in at 100 yds,
 by sighting-in at level firing
-------------------------------------------------------------------------------------
 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  2750  0.0000   2938    -1.9    0.0   -----     0.0   ------    -----    0.00
M   88  2622  0.0987   2670    +0.1    0.5    0.52     1.8     -0.1    -0.05    1.08
X  100  2604  0.1125   2635     0.0    0.6    0.58     2.4      0.0    -0.01    1.23
P  197  2467  0.2267   2365    -3.0    2.1    1.00     9.5     +4.2    +1.46    2.48
|  200  2463  0.2303   2357    -3.1    2.1    1.02     9.8     +4.4    +1.52    2.52
|  300  2326  0.3553   2103   -12.0    4.9    1.57    23.0    +11.2    +3.84    3.89
|  400  2194  0.4887   1871   -27.4    9.2    2.20    42.7    +19.1    +6.57    5.34
|  500  2066  0.6297   1659   -50.0   14.8    2.83    69.5    +27.8    +9.56    6.89
|  600  1942  0.7775   1465   -80.1   21.6    3.44   103.8    +37.1   +12.76    8.50
|  700  1823  0.9371   1291  -119.9   30.5    4.17   147.9    +47.6   +16.37   10.25
|  800  1710  1.1092   1136  -170.9   41.6    4.97   203.2    +59.4   +20.42   12.13
|  900  1602  1.2919    997  -233.8   54.6    5.79   270.4    +72.2   +24.83   14.13
| 1000  1500  1.4839    874  -309.1   69.2    6.60   350.0    +85.9   +29.54   16.23
| 1100  1405  1.6897    767  -400.3   86.2    7.48   445.5   +101.1   +34.77   18.48
| 1200  1319  1.9112    676  -510.7  106.0    8.43   560.1   +118.3   +40.66   20.90
| 1300  1240  2.1453    598  -640.6  128.0    9.40   694.3   +136.9   +47.07   23.46
| 1400  1173  2.3944    534  -794.4  152.6   10.41   852.3   +157.6   +54.20   26.19
| 1500  1115  2.6568    483  -973.9  179.6   11.43  1036.1   +180.4   +62.01   29.06
| 1600  1067  2.9320    443 -1181.8  208.8   12.46  1248.3   +205.2   +70.54   32.06
| 1700  1027  3.2186    410 -1419.7  240.1   13.49  1490.5   +232.0   +79.75   35.20
| 1800   993  3.5157    383 -1689.1  273.2   14.49  1764.1   +260.6   +89.61   38.45
| 1900   963  3.8223    360 -1991.2  307.9   15.48  2070.5   +291.0  +100.06   41.80
| 2000   936  4.1394    340 -2329.1  344.5   16.45  2412.6   +323.4  +111.18   45.27

 Tabular trajectory data at Non-Std. Atmosphere
 Gunsite altitude : 4500 ft.
 Air density      : 0.064951 lb./ft³
-------------------------------------------------------------------------------------
 Gun / Ammunition : 308 Win
 Bullet           : .308, 208, Hdy AMax
 Bullet weight    : 208 grains or 13.48 Grams
 Muzzle velocity  : 2550 fps
 Crosswind speed  : 10 Mph 
 Ballistic Coefficient(s) (G1): 
 C1=0.648@V>0 fps;


 Optimum trajectory information : 
 Optimum sight-in range (X) = 228 Yds. 
 with max. ordinate above LOS at range (M)= 130 Yds.
 and max. point blank range (P)= 267 Yds.
-------------------------------------------------------------------------------------
 Bullet path for firing up- or downhill! Angle of site/elevation 5 deg.
 Figures for velocity and energy relate to level firing.
 Sight-in clicks, 1 click = 1.0 cm/100 m or 0.394 in/100 m
 Height of sight above bore axis = 4.7 cm or 1.85 inch
 Gun is zeroed-in at 100 yds,
 by sighting-in at level firing
-------------------------------------------------------------------------------------
 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  2550  0.0000   3003    -1.9    0.0   -----     0.0   ------    -----    0.00
M   84  2454  0.0998   2782    +0.1    0.2    0.20     1.9     -0.3    -0.10    1.09
X  100  2436  0.1193   2741     0.0    0.3    0.28     2.7      0.0    -0.01    1.30
P  186  2341  0.2272   2531    -3.0    1.5    0.76     9.6     +4.5    +1.55    2.48
|  200  2326  0.2452   2498    -3.9    1.8    0.84    11.2     +5.5    +1.89    2.68
|  300  2218  0.3780   2271   -14.3    4.4    1.40    26.2    +13.3    +4.59    4.13
|  400  2113  0.5169   2062   -31.8    8.2    1.95    48.3    +22.2    +7.62    5.65
|  500  2010  0.6617   1867   -56.9   12.9    2.47    77.9    +31.6   +10.88    7.24
|  600  1911  0.8126   1686   -90.0   18.8    2.99   115.6    +41.7   +14.34    8.89
|  700  1815  0.9744   1521  -133.3   26.6    3.62   163.5    +53.0   +18.21   10.66
|  800  1723  1.1462   1371  -187.8   36.1    4.31   222.6    +65.3   +22.44   12.54
|  900  1635  1.3268   1234  -254.2   47.2    5.00   293.5    +78.5   +26.99   14.51
| 1000  1549  1.5152   1109  -332.7   59.6    5.69   376.7    +92.5   +31.79   16.57
| 1100  1468  1.7115    996  -424.5   73.5    6.38   473.0   +107.2   +36.87   18.72
| 1200  1393  1.9214    896  -534.0   89.7    7.14   587.1   +123.6   +42.51   21.01
| 1300  1323  2.1435    809  -662.4  108.1    7.94   720.1   +141.6   +48.67   23.44
| 1400  1258  2.3753    731  -809.7  128.2    8.74   871.9   +160.7   +55.24   25.98
| 1500  1200  2.6196    666  -980.2  150.5    9.58  1047.0   +181.5   +62.41   28.65
| 1600  1149  2.8751    610 -1175.3  174.7   10.43  1246.7   +204.1   +70.16   31.44
| 1700  1105  3.1414    564 -1397.2  200.9   11.28  1473.1   +228.3   +78.49   34.35
| 1800  1067  3.4178    526 -1647.7  228.8   12.14  1728.2   +254.3   +87.41   37.38
| 1900  1034  3.7035    494 -1928.1  258.4   12.99  2013.2   +281.8   +96.89   40.50
| 2000  1005  3.9979    466 -2239.9  289.5   13.82  2329.6   +311.0  +106.93   43.72

The 210 JLK with it's BC of .665 would seem like the best bullet to me, to really explore the outer reaches of the 308 Win. I've never tried them, but 1/10 twist is recommended. I might try some in my 1/10 30-06, and have an excuse to push a few down the 1/12 308 out of curiosity.

I have cut my 308 down to 20.5", and have not recorded 208/210 velocities in that length. At the original 26" length, I made 2600 fps via W760, and at 22", the same barrel made 2560 fps. At the current length, 2540 or so seems realistic. Of late though I've been shooting 155 Scenars at 2800 fps.

I hear through these forums that some of the F-TR class guns with thier 30+" barrels are achieving 2700 fps with the 208/210s.

 

[eddybo]

How long are you loaded rounds with the 208s MontanaMarine?

I am up to 51 grains of H4350 and am not seeing any pressure signs. My primers are still rounded to some degree for what its worth. I would really love to try and stuff enough vv560 in the case to get to 62k pressure, but am not sure it is even possible even using a drop tube. I came real close to running the reamer in .020 longer just to try and get it in there, but decided to wait on some RL17. Hopefully RL 17 will not be quite as bulky.

My bullets are just hanging in the necks and are jammed in the lands with 208s. I ordered some 190 bergers to try, but wish I had known about the JLKs. I may have throated it a bit long for the 190s to jam but will have to wait and see.

Just as an aside no one should try and stuff 51 grains of H4350 into a sami spec 308. I suspect that it would fire one very fast round, but only one.

 

[Marine sniper]

I cannot tell a difference in the accuracy potential between the 210 Berger and 208 AMax in my rifle. They are both very solid sub-moa accurate, often grouping below .5 moa.

IMR 4831 might be a tad bulky to get the mosr out of the limited volume in a 308 case, but will be curious to hear your results.

I try to maximize volume by using Win brass, then only resizing the neck. At OAL 2.95" I can put 49.0 gr W760 in there without excess compression, 50gr leaves a mark on the bullet from the seater, and "grows" a bit overnight. Might not grow with uncoated bullets, but I'm using moly.

VV N550 and RL17 look like good powders for the 208/210 also, but I don't have any firsthand experience with them.

Ya, the 4831 is too slow for sure, I did not realize I had some 4895 laying around. I have not reloaded for the 308 in over 10 years, I get 168 match ammo for free......I shoot a lot of bigger stuff usually, 300 Wby is the smallest rifle I load for.

The rifle I call my pack gun is a 308 with an 18 in. barrel. I will work up a load with 200 gr, accubonds, using the proper powder, and report back with what I end up with.

 

[MontanaMarine]

I'm loading the 208s to 2.95" OAL.

 

[Marine sniper]

I took my 210 loaded 308's to the range today and even with the velocity as low as 2250 fps they stabalized (12 twist), and had the exact same point of impact at 100 yards as my 168 Winchester match ammo.

FWIW, my load of 46 gr. IMR 4831, Rem 9 1/2 210 Berger just off the lands was good for 2350 fps in a 21 3/4 in barrel.

5 shot one hole group at 100 and a 10 shot group that went 3" at 300 in a 5 mph switching wind with no wind flags to help adjust for it.

I think I found somethign else to do with my 308 !!

 

[MontanaMarine]

Good deal.

 

[edge]

I took my 210 loaded 308's to the range today and even with the velocity as low as 2250 fps they stabalized (12 twist),

SNIP

Does anyone have the OAL of the 210 Berger?
If that is as long as I suspect that it is and it stabilizes in a 1:12 @ 2250 then I need to rethink some bullets that I have passed on in the past!

Any Barometric data or temperatures when you shot those loads?
Just wondering if it will still be stable in the Winter.... Thanks.

edge.

 

[Marine sniper]

Does anyone have the OAL of the 210 Berger?
If that is as long as I suspect that it is and it stabilizes in a 1:12 @ 2250 then I need to rethink some bullets that I have passed on in the past!

Any Barometric data or temperatures when you shot those loads?
Just wondering if it will still be stable in the Winter.... Thanks.

edge.

Dont know about the baro, but it was hot as hell, 95 in the shade. The range I shoot at is a little above sea level.

I have some SMK 240's I shoot in my 30-378. I should try a few in the 308 ! LOL !

 

[MontanaMarine]

Does anyone have the OAL of the 210 Berger?

I don't have a sample onhand to measure (shot them all), but QL database has them as 1.470"

I do have some 208 AMax on hand, they measure about 1.530"

 

[edge]

Thanks for the replies

I did not realize that the AMAX was so much longer.
Thanks again.

edge.