Home Forums Hunting & Shooting Hunting Rifles .308 Winchester with 165s and a 20" barrel

Does anyone know from first hand experience if a good (but still safe) handload from a .308 Winchester with 165 grain bullets fired from a 20" barrel can break 2700 fps?

Nosler also has a 165 grain Accubond factory load that is rated at 2800 fps. Anyone know what it would do from a 20" barrel?

From my three 20" rifles it's no. I haven't tried some of the latest powders though.

Okay - edited after I looked up chrono results. Used my oldest son's .308 Win, Browning BLR with a 20" barrel. Apparently only ran a couple of kinds of factory ammo through it, and I'm not sure this exact ammo is available anymore. Don't think so:

Federal 165 gr Trophy Bonded, 2608 fps avg

Federal 165 "High Energy" Trophy Bonded, 2761 fps avg

There ya go, that's all I've got... I don't think I ran any of my handloads through it that day, and I haven't borrowed back that rifle in a while...

Guy

Guy, I'm curious if you have compared your handloads to those factory loads in other rifles. It might still make for a usedful comparison.

It's interesting to see how some things work out. I have an old Ruger 77RSI Ultralight with an 18.5 inch barrel in .30-06. Using Hodgdon's maximum charge of H-4350 it does an honest chronographed 2715 fps from that short barrel and without any signs of pressure.

Fraser, I looked through my notes and found in '98 where I had played with a 20" .308 and 165s. The chamber was rather tight, and this was as hard as I dared run it.

The load consisted of:
Remington-Peters case
CCI BR2 primer
Varget, 44.4 grains

First was a Nosler ballistic tip.
OAL of 2.880", 2644 fps

Second was a Speer Flatbase Spitzer.
OAL of 2.800", 2647 fps

Third was the Hornady Flatbase Spitzer.
OAL of 2.800", 2655 fps


The Nosler bullet had a kinda high standard deviation, and the Hornady was more accurate than the Speer, but those results are with that particular rifle.

IME, 2700 with a 20" tube would be leaning on it fairly hard. But probably doable with Varget.

In my present 22" tube .308 I feel that 2700 and a 165 is about top end. That's with Varget as well.

Now others may come up with something else but this is what's been my experience.

Flip side is, if it's rolling at a good consistent 2650 or so what's it really matter...?

Just a thunk

Dober

With a 20" barrel, I got just a little over 2700 fps with a 150 gr bullet. With 165's, it was around 2600. But, a 165 Accubond at 2600 puts deer down quickly.

http://www.hornady.com/store/308-Win-165-gr-GMX-Superformance/

This link to hornady has a muzzle velocity of 2750 fps. Probably in a 24" barrel. So for a 20" barrel subtract a 100 fps.

.............Any cartridge`s capable velocities from a specific barrel length using a specific bullet and bullet weight will depend on the individual rifle bore and that rifle`s max pressure capability.

I don`t own a 308. But if I wanted to find the answer for a yes or no probability, I`d add up all of the max velocities listed for all 165 gr bullets using all powders and then divide that # by the # of loadings listed; Hodgdon and other manuals usually list velocities from 24" barrels. Then deduct about 20-25 fps (per inch) of shorter barrel length to account for the shorter 20" barrel length.

Hodgdon does show one interesting 165 gr 308 Win loading using their new CFE 223 (Copper Fouling Eraser). 2839 fps from their 24" barrel. 2839 fps minus 80 to 100 fps still gets you over 2700 fps.

Aside from that CFE 223 loading, Hodgdon lists max velocities from 2608 up to 2773 fps from the 24" barrel. You might get 2700 and a maybe a little better from some of them.

So I`d say that it is quite possible and highly likely to achieve 2700 fps using a 165 bullet from a 20" tube with no pressure signs.

But then again, that all depends on the rifle.

Yes it will.

RL15 will run just over 2,700. Varget will run just under 2,700.

2000MR will go just over 2,800 with a 165 NAB in a 22" bbl. Pretty safe to assume 2,750 will be easy with same in a 20" bbl.

My FN patrol rifle with 20" barrel chronographed 168 gr Sierra Match Kings at 2700 fps with 46 gr of Varget. I'm getting 2765 fps with that load in a 22" Kimber with the same powder charge and 165 Hornady interlocks.

In my experience 2700+ is easy with 165-168's in a 21-inch barrel, with published data, with more than one powder. It should be easily possible in a 20-inch barrel as well, since there isn't any practical difference.

Personally, I've found 150-155 grain bullets plenty for anything from the .308.

My opinion is the 165/168's are the "natural" bullet weight in the 308.

I guess my barrels are slow.

There are no "slow" barrels, there are just barrels not loaded to their full potential.

46 gr. of RL15 or Varget under a 168 was as hot as I went.

No doubt you could go to 46.5... you should "just" get 2,700 or a smidge less with a 20" barrel and Varget.

The .308 can actually use slightly slower powders than usual RL15/Varget/4895 with 165's. Also, there are newer powders.

Here's some data from 24" barrels, which shouldn't lose more than 100 fps from 20" barrels:

Hodgon CFE 48.3--2839
Ramshot Big Game 49.0--2790
Accurate 2530 47.7--2861

42.8 grains of Alliant AR-Comp is also listed at 2820 fps.

If I want to stand on it again I think I'll try the Hodgdon CFE.

I've been going the other way for a while now, 165/168 grains at 2550 propelled by IMR8208XBR about a half grain under max. Small groups, easy on me and the brass.

I've tried most of the .308-suitable powders and many 165-168 grain bullets in several rifles. While 2700+ is attainable with 22" barrels, you might make it with a 20". In a NULA 22", most accurate load has been 43 grs. H4895 with the Barnes 168 TSX BT. It appears to be a max. or near-max. load and clocks app. 2725.