Improving the 308 Win performance

[Gobbler256]

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.

I truly enjoy following these threads but I have 1 request for us novice loader/shooters.
Please, when you post a load please also provide your muzzle velocity for that load. This would be a big help in calculating ballistic data on the loads,
Thanks in advance!

 

[Dean2]

Well, I will add my 308 load. Shot out of a NULA with a 21" Douglas barrel, 130 grain Barnes TTSX, IMR 4895 powder and CCI250 primers. It is doing 3150 fps. Shoots on average .3, 3 shoot groups. No pressure signs, and 3 grains below book max. It will push a 150 grain bullet at 3000 fps using the same components and 1 grain less powder. There are no pressure signs and standard WW brass lasts 10 rounds easily. I see no reason to push it any harder. If I want more speed in a short action there is always the 300 PRC, but nearly double the powder to gain 200 fps, or the 300 Win Mag in the long action.

 

[bigngreen]

They say you have ti buy a gun strong enough to handle the pressure. In their marketing Sig says the object was to shoot a 140 gr bullet 3000 fps from a 16" barrel for a muzzle energy of just shy of 2800 ft- lbs. the cartridge is a necked down .308Win to a .277 caliber. The high pressure cartridge is a brass body with a stainless steel base to handle 80K PSI peak pressure. They compare that cartridge to the 5.56 currently in use. Thus the question about what SRP handles that kind of pressure?

Why would they need a steel base, we all know anyone running Lapua or ADG brass is running 80k already??

 

[mannup1515]

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.

 

[nralifer]

Well, I will add my 308 load. Shot out of a NULA with a 21" Douglas barrel, 130 grain Barnes TTSX, IMR 4895 powder and CCI250 primers. It is doing 3150 fps. Shoots on average .3, 3 shoot groups. No pressure signs, and 3 grains below book max. It will push a 150 grain bullet at 3000 fps using the same components and 1 grain less powder. There are no pressure signs and standard WW brass lasts 10 rounds easily. I see no reason to push it any harder. If I want more speed in a short action there is always the 300 PRC, but nearly double the powder to gain 200 fps, or the 300 Win Mag in the long action.

Sounds like a good load. You could improve it by using a 150gr BD2 Badlands bullet. BC better than Barnes or Berger of the same weight and expansion is very reliable and predictable down to 1700 fps impact velocity. That makes a superb hunting load in a compact easily manipulated rifle with a very stiff barrel with a highly penetrating bullet and low recoil even without a muzzle brake.

 

[Dean2]

Sounds like a good load. You could improve it by using a 150gr BD2 Badlands bullet. BC better than Barnes or Berger of the same weight and expansion is very reliable and predictable down to 1700 fps impact velocity. That makes a superb hunting load in a compact easily manipulated rifle with a very stiff barrel with a highly penetrating bullet and low recoil even without a muzzle brake.

Being in Canada limits bullet choice. I have never seen Badlands bullets for sale up here, Hammers just became available a couple of years ago.

Even though the rifle only weighs six pounds, loaded, sling and scope, I do not find the recoil bad at all. I have shot big boomers all my life, I find the 308 a very mild recoiling rifle. Except for the 460 Bee, I have never used a brake on a rifle I am hunting with, target shooting they are great.

 

[Mike D Texas]

What app is this?

That's from my Labradar.

 

[Son of a Gun!]

Sounds to me like you're trying to make a 308 perform like a 300 Magnum! From my experience with a short barrel you can get a little over 2800 fps with a 150 gr. bullet without pressure signs! My favorite load in my Rem. Mdl. 7 SS with 20" bbl. was a 165 gr. Nosler Partition at about 2750 fps. This was my Daughter's elk hunting rifle! She never shot anything over 250 yds. I realize there are newer powders out there that give better performance! I loaded up some 150gr. SSTs and 50.5 grs. of CFE223 for my grandkids Ruger American Youth 181/2" bbl. and they clocked 2882 fps. but accuracy was lacking! I went back to olde school and 43 grs. IMR 3031 for 2765 fps. They have killed Antelope Whitetail and Mule Deer with this load out to 200+ yds.

 

[nralifer]

Being in Canada limits bullet choice. I have never seen Badlands bullets for sale up here, Hammers just became available a couple of years ago.

Even though the rifle only weighs six pounds, loaded, sling and scope, I do not find the recoil bad at all. I have shot big boomers all my life, I find the 308 a very mild recoiling rifle. Except for the 460 Bee, I have never used a brake on a rifle I am hunting with, target shooting they are great.

We have to use an exporter. You could PM me and I could help you if you want.

 

[Dean2]

I appreciate the offer and may take you up on that in the future. Other Canadians reading this may well be interested also. Thanks.

 

[nralifer]

I appreciate the offer and may take you up on that in the future. Other Canadians reading this may well be interested also. Thanks.

Thanks so much. Don't feel obliged to place an order, but that way I can give you the contact info for our exporter and the process to place orders.

 

[lobo56]

Remember the old saying, "There is no substitute for cubic inchs". -Mr "Grumpy" Jenkins.

And boy are they making those big "cubic Inches" now! ;-)

 

[Flatlandcoaxer86]

Maybe you should do the math. The G1BC of the 150 gr .308 BD2 bullet is 0.515. At 3050 fps, which I get all the time from my 24" 1:9 Bartlein using a SAAMI 308 chamber loaded to 2.980" to mag feed at 5000 ft elevation which is where a lot of Elk hunting is done, at 59degreesF 50% humidity and 1 ATM corrected to that altitude the bullet at 900 yds is going over 1800 fps and has 1080 ft# energy. The bullet expands at 1700 fps impact. A 150 gr copper Etip in a 3006 per listed data in the 2021 Hodgdon Annual Manual from a 24" barrel has a max listed MV of 2947 fps. The BC of that bullet is listed at G1=0.469 (see Noslers pic below). I did not propose this thread to argue the point of whether the 308Win is better or worse than anything else. I apologize if you are getting that impression. The purpose of the thread is to stimulate discussion on what modern components can improve the performance of the 308 Win with the idea that concepts developed along similar lines could do the same for other cartridges. In my mind there are quite a few things that can be done beyond just using a higher energy powder. I would like to see what other guys have done along those lines.

You are all over the place dude. 150, 175, 22" barrel, 24" barrel, should do this, Ive done that. Make up your mind

 

[nralifer]

You are all over the place dude. 150, 175, 22" barrel, 24" barrel, should do this, Ive done that. Make up your mind

Not sure what you mean. The 308 data I quoted is not from a 22" barrel, it was from a 20" barrel. The bullet used was of a higher BC than those in published data, and in an equivalent length barrel as the data on the 3006 was gathered from, that 308 load pushes that 150gr bullet 100 fps faster and will go farther than the 3006. The greater powder capacity of the 3006 case using the higher BC bullet should be able to out do the 308 theoretically. The point is that both the 308 AND 3006 performance, with higher BC bullets, higher energy powders, and brass that can safely handle higher pressures i.e. better components, should improve well beyond historical norms. If you have a 3006 and you want to improve its performance, do some experimenting an bring your data to this thread. Many would welcome it including myself.