Improving the 308 Win performance

[Dot_3]

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.

Why not stuff the same BD2 bullet into a 30-06 case with about 60 grains of RL19? Like was mentioned earlier, the same advancements help the -06 as much as any other any cartridge. How's the saying go? A rising tide lifts all ships

 

[Capt RB]

Anything you do in a 308 add 125-150fps in the 06. If you really push the edge of it you can see 200fps differences in heavy bullets. As long as you compare things with the same standard

 

[sierracharlie338]

I want to see the 175 class bullets going 2900 out of a 308. Not saying it can't be done but it would be dam sure impressive if they did!

 

[nralifer]

What is "better"?
Flatter trajectory? Use a lighter bullet
More energy? Use a heavier bullet
More speed? Use a longer barrel or some of the newer powders.
More energy at subsonic speeds? Use the heaviest bullet your twist will allow.
You can try a bullet with less engraving pressure/shorter bearing length to increase your speeds too--certain monos and cup/core bullets would fall under this area

But every cartridge has its limitations


Ive gotten a178 ahh up to 2950fps from a 21" 30-06.
I havent had time yet to fool with that bullet in the 308, but I will try it at some point.

Just remember that you'll need enough energy for the animal you're hunting AND you'll need enough speed for reliable expansion for the bullet your using.

What is considered better is significant extension of effective range. Since this is primarily a hunting forum that effective range extension applies to useful hunting rifles, not 30-50 lb ELR rifles. All the parameters you mentioned play a role. In other words, what can one do to improve the performance of their own hunting rifle without having to buy a new one. The 308 is a good platform to experiment with because it is ubiquitous and relatively inexpensive to shoot.

 

[nralifer]

I want to see the 175 class bullets going 2900 out of a 308. Not saying it can't be done but it would be dam sure impressive if they did!

I agree. I'm ready to try it. Might have some results on Wed next week when the temp gets above 0 so I can use my radar.

 

[TRexF16]

Of course - the .308's performance can be improved upon from "what it was." But to follow on your examples above, every technology you'd use to do so would apply equally to the 30-06, and thus the .308's potential would never match the 30-06's potential.

It's just math. But that said, whatever you can do to safely improve on your .308, is a good thing. Have at it!

Merry Christmas,
Rex

 

[Calvin45]

if you give the .30-06 the same improvement treatment you're giving the .308 it will continue to trash the .308.

 

[Beluebow]

You can run a Berger 200-20x at 2650fps out of a 308w and get basically the same results.

Case capacity wins when you compare 30-06/308.

 

[Calvin45]

That being said, one performance window that had opened up with any old school 30 has to be with the 120 Barnes tac tx originally meant for .300 blackout. With a .358 g1 bc (and probably much higher at non .300 blk velocity) and the .308 easily being able to break 3000 fps by a lot, you legit emulate the original .270 Winchester performance with a lot less powder.

Or run them at 4050 fps out of a magnum. It's what I do

 

[asd9055]

That being said, one performance window that had opened up with any old school 30 has to be with the 120 Barnes tac tx originally meant for .300 blackout. With a .358 g1 bc (and probably much higher at non .300 blk velocity) and the .308 easily being able to break 3000 fps by a lot, you legit emulate the original .270 Winchester performance with a lot less powder.

Or run them at 4050 fps out of a magnum. It's what I do

Calvin would that be the 300WBY or a RUM?

 

[Reelamin]

......This load would be a pretty decent long range Elk load to 900 yds or so.

I believe, Yes it PROBABLY would with perfect shot placement kill an elk slowly and miserably at this yardage or even further.

 

[Alibiiv]

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'm interested in this post, but….what's a "150 gr BD"?? I'm just starting load development for an Aero Precision in .308, interested in others exeriences

 

[Calvin45]

Calvin would that be the 300WBY or a RUM?

Believe it or not a boring old .300 win mag.

Peterson brass, hexagonal boron nitriding the bullets and bore of the rifle, and the ultra dense progressive burn rate Superformance powder make it possible. 26 inch.

 

[Mike D Texas]

I want to see the 175 class bullets going 2900 out of a 308. Not saying it can't be done but it would be dam sure impressive if they did!

Steven I have had a 168 ABLR over 2970 out of my 20" 308 5R with CFE223.

They just don't shoot worth a flip.