Improving the 308 Win performance

This thread would be dedicated to ways to improve the performance of the 308 Win or the 7.62x51 mm cartridge without wildcatting the case. Experienced and innovative reloaders should find this interesting and are encouraged to participate. The 308Win is so versatile, inherently accurate and commonly used, and yet its performance in terms of MV, trajectory and speed is a bit mediocre. I am sure it can out perform the 3006. To start with I offer up my favorite hunting load I have used for the past 6/7 years in the 308Win. The 150 gr BD or BD2 with 49 gr of Leverevolution going 2920 fps from a 1:10, 20"Douglas barrel in a short action rifle. The same load from a 24" Bartlein 1:9 twist barrel goes 3050 fps. This load would be a pretty decent long range Elk load to 900 yds or so.
How much performance do ya want out od a 308 case no modification? How about over 3600 to 3700 ft lbs of energy with a 200 gr SMK .715 g1 BC going 2856 fps standard load or 2952 fps special bi metal case load. Or 225 ELDM at 2719 fps .777 g1 BC. Or 168 gr match at 3255 fps ...all from a 308 case fit any 308 factory chamber. I have experimented with the 308 for over 30 yrs. And have long action, short action, barrels from 18" to 30" and twists 12, 10, 9, and 8 available. And cases from most every manufacturer, LC military, WW, Lapua LR and SR, and necked up bi-metal 80kpsi 6.8x51mm special run Sig cases.
The best preforming 308 bullet is the 200 SMK .715 BC requiring a 9 twist where a 22" Bartlein light hunting rifle will run them at 2740 fps with standard brass Lapua case. Should cluster 10 rds in 1" at 100 yds. I went from light to heavy bullets in 308 the 225 ELDM .777 BC is another good bullet, at 2675 fps Lapua case 30" Bartlein Palma 8 twist barrel very accurate, 5 shots .3" this was built on a long action and feeds long cartridges from a detachable 30-06 mag. This rifle is set up for 250gr Atips, but I like the performance of the 200 SMK so I didn't extend the throat to get max performance out of the 250 gr Atip bullets. And the 18" A R can run the 200gr SMK at 2672 fps in single load mode. So I'd run the long range 308 24" 9 twist with the 200 gr SMK around 2800 fps. I've never shot anything but varmints with a SMK at 1000 yds. Killed all the big game inside 100 yds, every elk and all deer except 1 at around 600 yds ...hunted the rainforest on the coast, the mountains and high desert. Killed at least one third on a full run ...ya only get a second to shoot or their gone, went with the new 7 mm mag, then the 338 Win mag and 350 Rem mag modified rifle to shoot 250 gr at 2626 fps ave 20" barrel for fast up close moving shots. Used a 2-7 X or a 3-9X hunt on lowest power, cause it's like a pheasant busting from cover and ya got to make the kill instaniously, usually on a full run in heavy cover. Shot a big buck out in the desert on the run with his group of does ... the lead doe saw me and turned the group, I could see the back of the buck hiding in the running herd of does, he moved slightly to the back, exposing his flank, I shot him in the flank muscles to slow him down, which it did and exposed the chest, and I shot him in the chest and killed him ...a huge cowardly buck in the rut maybe 75 to 80 yds on a full run, out in the middle of the desert, sage brush & flat ground nothing for miles. And the world's worst tasting meat, along with antelope, and bear. Bull elk was a little better, then they started getting lots of parasites in the liver and flesh...went back to varmint shooting where I do shoot over a thousand yards...but that has changed too.
Now mostly targets and steel, and experimenting.
 
So far so good. I have not with my 308 18" bolt gun. My son in law killed a nice Coues buck (below) with that same load from his 308 with a 24" barrel, 540 yards, DRT. Higher velocities with the 24" barrel up near 3200-3225.That being said we're moving to the 150 bullets in the BD2. Testing this weekend, hopefully tomorrow at the Pima County range out by the fairgrounds.
Cool, I'll come watch ;) (jk)

Let us know how it goes. I just got my 308 barrel back from being cut down to 18" and threaded so I'm about ready to start working up some new loads for it.
 
This thread would be dedicated to ways to improve the performance of the 308 Win or the 7.62x51 mm cartridge without wildcatting the case. Experienced and innovative reloaders should find this interesting and are encouraged to participate. The 308Win is so versatile, inherently accurate and commonly used, and yet its performance in terms of MV, trajectory and speed is a bit mediocre. I am sure it can out perform the 3006. To start with I offer up my favorite hunting load I have used for the past 6/7 years in the 308Win. The 150 gr BD or BD2 with 49 gr of Leverevolution going 2920 fps from a 1:10, 20"Douglas barrel in a short action rifle. The same load from a 24" Bartlein 1:9 twist barrel goes 3050 fps. This load would be a pretty decent long range Elk load to 900 yds or so.
How much performance do ya want out od a 308 case no modification? How about over 3600 to 3700 ft lbs of energy with a 200 gr SMK .715 g1 BC going 2856 fps standard load or 2952 fps special bi metal case load. Or 225 ELDM at 2719 fps .777 g1 BC. Or 168 gr match at 3255 fps ...all from a 308 case fit any 308 factory chamber. I have experimented with the 308 for over 30 yrs. And have long action, short action, barrels from 18" to 30" and twists 12, 10, 9, and 8 available. And cases from most every manufacturer, LC military, WW, Lapua LR and SR, and necked up bi-metal 80kpsi 6.8x51mm special run Sig cases.
The best preforming 308 bullet is the 200 SMK .715 BC requiring a 9 twist where a 22" Bartlein light hunting rifle will run them at 2740 fps with standard brass Lapua case. Should cluster 10 rds in 1" at 100 yds. I went from light to heavy bullets in 308 the 225 ELDM .777 BC is another good bullet, at 2675 fps Lapua case 30" Bartlein Palma 8 twist barrel very accurate, 5 shots .3" this was built on a long action and feeds long cartridges from a detachable 30-06 mag. This rifle is set up for 250gr Atips, but I like the performance of the 200 SMK so I didn't extend the throat to get max performance out of the 250 gr Atip bullets. And the 18" A R can run the 200gr SMK at 2672 fps in single load mode. So I'd run the long range 308 24" 9 twist with the 200 gr SMK around 2800 fps. I've never shot anything but varmints with a SMK at 1000 yds. Killed all the big game inside 100 yds, every elk and all deer except 1 at around 600 yds ...hunted the rainforest on the coast, the mountains and high desert. Killed at least one third on a full run ...ya only get a second to shoot or their gone, went with the new 7 mm mag, then the 338 Win mag and 350 Rem mag modified rifle to shoot 250 gr at 2626 fps ave 20" barrel for fast up close moving shots. Used a 2-7 X or a 3-9X hunt on lowest power, cause it's like a pheasant busting from cover and ya got to make the kill instaniously, usually on a full run in heavy cover. Shot a big buck out in the desert on the run with his group of does ... the lead doe saw me and turned the group, I could see the back of the buck hiding in the running herd of does, he moved slightly to the back, exposing his flank, I shot him in the flank muscles to slow him down, which it did and exposed the chest, and I shot him in the chest and killed him ...a huge cowardly buck in the rut maybe 75 to 80 yds on a full run, out in the middle of the desert, sage brush & flat ground nothing for miles. And the world's worst tasting meat, along with antelope, and bear. Bull elk was a little better, then they started getting lots of parasites in the liver and flesh...went back to varmint shooting where I do shoot over a thousand yards...but that has changed too.
Now mostly targets and steel, and experimenting.
 
With that bullet and MV it looks like you only have around 1800fps impact velocity for 600yds (used JBM with 5000' elevation). Are you getting pretty good expansion at that velocity with those Barnes bullets?
You should try the Badlands 150 gr .308 BD2 bullet using 48-50 gr Leverevolution. Do a small 2 shot ladder at 0.025" off the lands. They have a substantially greater BC and at 600 yds you should have substantially greater retained velocity and bullet energy. I would expect to get an MV of 2900 fps or so.
 
How much performance do ya want out od a 308 case no modification? How about over 3600 to 3700 ft lbs of energy with a 200 gr SMK .715 g1 BC going 2856 fps standard load or 2952 fps special bi metal case load. Or 225 ELDM at 2719 fps .777 g1 BC. Or 168 gr match at 3255 fps ...all from a 308 case fit any 308 factory chamber. I have experimented with the 308 for over 30 yrs. And have long action, short action, barrels from 18" to 30" and twists 12, 10, 9, and 8 available. And cases from most every manufacturer, LC military, WW, Lapua LR and SR, and necked up bi-metal 80kpsi 6.8x51mm special run Sig cases.
The best preforming 308 bullet is the 200 SMK .715 BC requiring a 9 twist where a 22" Bartlein light hunting rifle will run them at 2740 fps with standard brass Lapua case. Should cluster 10 rds in 1" at 100 yds. I went from light to heavy bullets in 308 the 225 ELDM .777 BC is another good bullet, at 2675 fps Lapua case 30" Bartlein Palma 8 twist barrel very accurate, 5 shots .3" this was built on a long action and feeds long cartridges from a detachable 30-06 mag. This rifle is set up for 250gr Atips, but I like the performance of the 200 SMK so I didn't extend the throat to get max performance out of the 250 gr Atip bullets. And the 18" A R can run the 200gr SMK at 2672 fps in single load mode. So I'd run the long range 308 24" 9 twist with the 200 gr SMK around 2800 fps. I've never shot anything but varmints with a SMK at 1000 yds. Killed all the big game inside 100 yds, every elk and all deer except 1 at around 600 yds ...hunted the rainforest on the coast, the mountains and high desert. Killed at least one third on a full run ...ya only get a second to shoot or their gone, went with the new 7 mm mag, then the 338 Win mag and 350 Rem mag modified rifle to shoot 250 gr at 2626 fps ave 20" barrel for fast up close moving shots. Used a 2-7 X or a 3-9X hunt on lowest power, cause it's like a pheasant busting from cover and ya got to make the kill instaniously, usually on a full run in heavy cover. Shot a big buck out in the desert on the run with his group of does ... the lead doe saw me and turned the group, I could see the back of the buck hiding in the running herd of does, he moved slightly to the back, exposing his flank, I shot him in the flank muscles to slow him down, which it did and exposed the chest, and I shot him in the chest and killed him ...a huge cowardly buck in the rut maybe 75 to 80 yds on a full run, out in the middle of the desert, sage brush & flat ground nothing for miles. And the world's worst tasting meat, along with antelope, and bear. Bull elk was a little better, then they started getting lots of parasites in the liver and flesh...went back to varmint shooting where I do shoot over a thousand yards...but that has changed too.
Now mostly targets and steel, and experimenting.
This is interesting data. From a 3006 length action and a 30" 1:8 twist barrel you can get substantially greater MV using heavy bullets just by virtue of the longer barrel and seating the bullet out further. Since you seem to be an experimentalist you should try the Badlands 205 gr SBD2 bullet with a G7 BC of 0.370 which is greater than the 200 gr SMK. I would recommend the Lapua Palma brass using Leverevolution and a CCI450 primer. It is a superior hunting bullet than the SMK. Your 1:8 barrel should work well.
 
So far so good. I have not with my 308 18" bolt gun. My son in law killed a nice Coues buck (below) with that same load from his 308 with a 24" barrel, 540 yards, DRT. Higher velocities with the 24" barrel up near 3200-3225.That being said we're moving to the 150 bullets in the BD2. Testing this weekend, hopefully tomorrow at the Pima County range out by the fairgrounds.
And that's what matters.. plenty to put a coues down at 600 yards DRT. It's not an elk or moose.
 
So 150 BD2 in new virgin Alpha SRP brass, COAL 2.910, 49 LeverEvo, CCI SRP mag primer, no pressure, 3058 FPS average, SD of 12, in 18" 1/10 barrel. Accuracy is MOA or slightly better. Outdoor temp 92. I can get this better with changing seating depth and once I fully prep fired brass.

Went to 49.5 and had beginnings of flattening on primers.

I'm going to back off to 48 and work up in .02 increments and see what I get. I'm still at the range but will do a H20 capacity later today or tomorrow.

Good day gents!
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This is interesting data. From a 3006 length action and a 30" 1:8 twist barrel you can get substantially greater MV using heavy bullets just by virtue of the longer barrel and seating the bullet out further. Since you seem to be an experimentalist you should try the Badlands 205 gr SBD2 bullet with a G7 BC of 0.370 which is greater than the 200 gr SMK. I would recommend the Lapua Palma brass using Leverevolution and a CCI450 primer. It is a superior hunting bullet than the SMK. Your 1:8 barrel should work well.
I checked out the Badlands Bullets site...thanks for the info... their company is right where I used to live in farm and ranch county and Souix Indians ...actually been there.
 
This is interesting data. From a 3006 length action and a 30" 1:8 twist barrel you can get substantially greater MV using heavy bullets just by virtue of the longer barrel and seating the bullet out further. Since you seem to be an experimentalist you should try the Badlands 205 gr SBD2 bullet with a G7 BC of 0.370 which is greater than the 200 gr SMK. I would recommend the Lapua Palma brass using Leverevolution and a CCI450 primer. It is a superior hunting bullet than the SMK. Your 1:8 barrel should work well.
Thanks for the tip on Badlands Bullets, checked them out...may try some to see how they shoot, I don't hunt anymore the last few yrs, getting too old. But still get quite a bit of shooting done. I already use the Lapua Palma 308 brass and their LR primed brass. I've used both Rem 7 1/2 and the CCI 450 in the palma brass. The plama brass tends to lose 40 fps with the same load as the LR Lapua brass in one comparison test...needs to be explored ...but a 1/2 gr more powder could be added to the Palma case..maybe. I have the special not to be reloaded 277 Fury bi-metal cases formed and ready to load for experimental purposes, as they are rated at 80,000 psi. I have a bunch of Leverevolution for the 6mm ARC but never tried it in 308...in the special bimetal cases I'm running the 6.5 Creedmoor at 3000 fps with 150 gr SMK, 3056 fps being the top load. And continued experimenting on the 308. I have a 22" 9 twist to play with also built as a lighter weight hunting rifle.
 
So 150 BD2 in new virgin Alpha SRP brass, COAL 2.910, 49 LeverEvo, CCI SRP mag primer, no pressure, 3058 FPS average, SD of 12, in 18" 1/10 barrel. Accuracy is MOA or slightly better. Outdoor temp 92. I can get this better with changing seating depth and once I fully prep fired brass.

Went to 49.5 and had beginnings of flattening on primers.

I'm going to back off to 48 and work up in .02 increments and see what I get. I'm still at the range but will do a H20 capacity later today or tomorrow.

Good day gents!
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Those are excellent speeds from an 18" barrel and the photo of your primer indicates no significant flattening. Very good that you tested these loads at 92 degrees. I can see a little cratering but I don't think that is a reliable pressure indicator. I see some cratering in all Savage actions I have regardless of the degree of primer flattening.
 
Those are excellent speeds from an 18" barrel and the photo of your primer indicates no significant flattening. Very good that you tested these loads at 92 degrees. I can see a little cratering but I don't think that is a reliable pressure indicator. I see some cratering in all Savage actions I have regardless of the degree of primer flattening.
I know some of your data shows a slower MV with the same charge and a 20" barrel. Possibly due to using a 9 twist barrel you think?
 
I know some of your data shows a slower MV with the same charge and a 20" barrel. Possibly due to using a 9 twist barrel you think?
My experience says that can be a small factor, however each rifle barrel is different (even the same manufacturer, length, and twist). With the 64 .300 WinMags I we had in our vault, we experienced a 300 fps variation from fasted to slowest. This is with same ammo, conditions, etc.
 
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