Home Forums Hunting & Shooting Long Range Hunting Fastest safe .308 win round you have worked up?

I'm planning on reaming mine out with a slightly wider 30 degree shoulder, long-throated, 22 inch barrel to keep it very short, using the 165 grain Sierra TGK with a reasonable bc of .530, good sectional density and running temperature stable Varget at 2800+ fps using Winchester 7-08 brass to give a longer neck.

Buy a dialing scope and ignore velocity if that matters to you. The difference in even 100fps in a .308 is nearly insignificant in the field

Killed an antelope Tuesday with a 125 gr TGK with a load of TAC that averages 3227 fps. This is in line with Sierra's data and is a grain under their published maximum. If anyone is curious, the bullet exited on a broadside shot, destroyed 2 ribs and made a mess of his insides.

Running this idea through Quickbook, you'll theoretically gain around 36 fps with the improved 308 over the standard 308, when both are loaded to 3.0" (and that's using an Ackley, not the 30 degree, which may show a tad more improvement over your round). If ordering custom dies, time involved in the project, smithing fees, and possible feeding problems seem worth it, go for it, but you'll never see a difference anywhere other than your chronograph, plus gaining a lighter wallet or higher credit card bill.

I think mine will feed ok as I have already done it in another bore, I'll just use the same reamer. It may hold the same as the Ackley as the shoulder is more forward on the neck than the Ackley (that's why I will use 7-08 brass, plus I lose about .010" when fireforming), but the greater shoulder slope reduces powder capacity...should be about the same. Gain will be about 50 fps I estimate, being a combination of a few more grains of powder and running slightly higher pressure because of the straighter walls and shoulder angle. Dies take 2 years from CH4D. I made up a dummy round and it looks good. I agree that the difference is not noticeable, but there is a difference and I'm happy to experiment and get a slight improvement. It's sort of a bit interesting to me. The benefit is a 22" barrel with a short action, a projectile with good weight - 165 gn , good sectional density, good bc at 2800 fps or more (depending on where accuracy is best) with a temperature stable powder, negligible case stretching. The long-throating also gives some benefit with the 165 gn projectiles, but the usual lead core 150's especially with boat-tails won't have much grip on them or are too far from the lands for accuracy usually.

Exactly. Why try to make the .308 one?

There's no denying the .308 Win is a good hunting round, but it doesn't exist in a vacuum. There are other rounds (such as the 7-08, .30-06 and even the less powerful .300 Savage) that have some slight advantages in some areas but have disadvantages in other areas when compared to the .308 Win. By tweaking the .308 Win, you can attempt to erode or eliminate the advantages that other rounds have over the .308 in the areas that they have those advantages, whilst at the same time, keeping most of the advantages the .308 Win has over the other rounds. And the beauty of it is, those who want to stick to their current way of doing things with their .308 can...they don't have to change one bit!

I don't fret 100fps in my 308... the elk I've shot with 168's at 2650 fps MV died PDQ. That being said, 150's at 2850 are about as fast as I've seen in my hunting rifle.

What barrel length?

A 150 at 2850 is doable with book loads out of my 22" factory Remington barrel.

If a guy is looking for more performance, going to a 7mm with its sleeker bullets makes more sense than fiddling with a 308. Also, pushing the shoulder forward to make a sort of Gibbs version of the 308 negates the use of factory ammo, which is one of the handier reasons to use a 308 to begin with. But oh well, to each his own.

The .308 pushes heavier bullets faster than the 7-08 and gives a wider wound channel. If you reload, why use factory ammunition? The .308 or 7-08 brass is still used if you slightly improve the case. And if you don't want to modify the case, then you don't do it. Bye the way, you're looking at about 51 grains of powder to the base of the neck.

I don't have either of those bullets, BUT...

22" barrel.

165 Hornady Interlock BTSP, Nosler case, 41.5 H-4895, Fed 210, OAL 2.815 .020 off, 2678fps
168 Nosler Billistic Tip.........., Nosler case, 41.5 H-4895, Fed 210, OAL 2.930, 030 off, 2642fps

155 Scanar OTM, Nosler case, 44.0 H-4895, Fed 210, OAL 2.820, .050 off, 2881fps

Dang, we're approaching mid-winter levels of pedantry.

Right!

The thread's about fast .308s, not about moderate loads. Some people such as myself don't accept the proposition that "although the .308 is good, the 7-08 is better".

Some people have brains and are functional. They buy the right tool for the job. If the job changes they buy a different tool.

And what might be the right tool for the job of "fastest safe .308 Win round you have worked up" Mr High IQ?

The question is posed on “Long Range” forum. Fastest doesn’t correspond to long range. A 150 gr lower BC bullet at 2,900 fps plus isn’t as effective nor precise in combating wind drift as a high BC 180 gr bullet at 2,600 fps out at 500 yds. The 308 Win made its military target bones using a 168 gr bullet at 2,570 fps. What are you really trying to accomplish with the 308 Win? Just my observation.

Typical Speeds, give or take per most loading manuals.
130gr class @ 3,100 fps
150gr class @ 2,925 fps
165gr class @ 2,735 fps
180gr class @ 2,625 fps
200gr class @ 2,450 fps

Getting each of those different weight projectiles going faster, provided accuracy is there, will be slightly better for long range e.g. a 165 at 2800 as I advocated.