Ballistics people, Help me decide on a .308 load.

[Mitch Rapp]

Background first, my rifle is a Savage 10 fp 5r with a 20 inch heavy barrel. I have a good mid range 168 bthp load that groups tight, and that I plan to keep learning with. What I want is a good hunting load that will also take me to 1k on targets. I have narrowed it down to two bullets, either the 178 or 208 Amax. The 178 according to my Shooter app at a MV of 2550 will drop 43.1 MOA and drift 117.3" with a ten mph wind, and be going 1060fps The 208 with a 2350 MV will drop 42.2 but will drift only 87" in a ten mph wind, and be moving 1220 fps. Drop the MV on the 208 down to 2300 and it still looks better than the 178.

The biggest difference I see is there is a decent amount of history supporting the 178 as a reliable performer. With the 208s most of the data is from guys with custom chambers that can seat the bullet way out so they still have plenty of case capacity. They talk about getting the 208 over 2500. I think 23-2350 is doable with with a 20 inch bbl and non "hot" loads, loaded to magazine length.

What do yall think? Use 178s and stick with known info, or see what can be done with the heavies? Do my numbers sound reasonable? I used the Litz data on both, and I think the velocties on both are reasonable.

Poke some holes in my thinking, or make suggestions please!



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[swampratt]

I would try them both in your gun as it may not like one of the bullets and accuracy could be way off with one vs the other.
My groups at 100 yards with the 178 in my 10fp was in the .3" range. but it opened up to 6-7" at 300 yards if i was lucky i could get 6" at 300..I gave up on that 178.. maybe i just never found the load it liked.

 

[MoBoost]

I shoot 178s @ 2500 fps. (43.0 Varget).

Heavies kick like a mule.

 

[Mitch Rapp]

I shoot 178s @ 2500 fps. (43.0 Varget).

Heavies kick like a mule.

What length barrel?

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[distantfoe]

Might look into the 155gr bullets running 2850-2900. I seem to remember. they have an edge over the heavies at 308 velocities.

 

[Mitch Rapp]

Might look into the 155gr bullets running 2850-2900. I seem to remember. they have an edge over the heavies at 308 velocities.

You need a longer barrel for those velocities

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[distantfoe]

You need a longer barrel for those velocities

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OOPS, didn't see the 20' Although here's some useful info off accurateshooter.com using 25-26" bbl and obtainable velocities with 155s
Alliant Reloader 15

46.2

CCI BR2

Lapua 155

Lapua

2920 fps

Very Accurate in 25″ 5R bbl, .3 MOA at 300m, 2.800″ COAL



Hodgdon Varget

45.2

F210m

Lapua 155

Lapua

2830 fps

Z. Smith Tactical Match Load in 24″ Accuracy Int’l, 2.850″ COAL

 

[magna19]

I would try them both in your gun as it may not like one of the bullets and accuracy could be way off with one vs the other.
My groups at 100 yards with the 178 in my 10fp was in the .3" range. but it opened up to 6-7" at 300 yards if i was lucky i could get 6" at 300..I gave up on that 178.. maybe i just never found the load it liked.

Is that possible for those bullets to go from .3 groups @100 yds. then 6-7" groups @300yds.

 

[swampratt]

I say i can't lie when it is all on paper...
The .376" group i shot was at 117 yards and the 300 yard was an eye opener...
I have a .307" diameter 150gr flatnose that i shoot from the .308 at 2940fps and it bug holes at 50 yards and opens up
to just under 1" at 100
The 165 game kings are much larger at 50 yards than at 100...
Only way to know what a bullet will do is to shoot it and see.

I have guns that follow "Normal thinking" a 30-30 loaded with 150gr flatnose and my 30-06 loaded with 150gr flatbase
I get ..550"-.990" @100 with the 30-06 and shot 2.25" @300
The 30-30 will do 1.5-1.75 at 100 and 3-3.5" at 200 yards.

Now i even tried the 178 in my 30-06 got terrible groups at 300 yards..looked great at 100.
That same shooting session is when i shot the 2.25" group from the 30-06 at 300 with my flat base.
Maybe i needed to speed them up or slow them down. Flat base had less drop

I tried them at 200 also and my flat base had less drop then and out shot the 178.

I made a decision...my guns are used for deer and bird hunting and i don't get many shots past 300 yards.
So use the bullet and load that performs best for me at the ranges i shoot.

You guys must get out somewhere and try shooting your loads at many different distances..do not assume it will follow normal thinking flight patterns.

I shot a deer in the shoulder while aiming at a neck with the 178 in my .308..That made me test like i stated above.

I had an sks and shot 110 yards at the boiler room on a deer and hit the neck...
every 20-30 feet i stepped back and shot made the bullet land in a different spot..
The pattern looked like a spiral.. a big spiral...I sold that gun to a buddy...he wanted it and eventually found some ammo it shot great with.

At least he thinks so // as he stated it is his most accurate gun...We need to get together and go to the red river and shoot .
Wish i was there on this beautiful opening morning
Good luck to all who are in the woods today!!!