308 Winchester using Winchester 748 Powder

[bluejay75]

Greetings Gents,

I’m banging my head against the wall wanting more out of my 308 Cast loads. Is there anyone who has tried this combo. I have molds that can cast from 150 grains to almost 200 grains.

Feel free to share any suggestions you might have. I’m wanting about 2400-2500 FPS with a 180 grain.

Thanks in advance.

Bluejay

[Markopolo]

wow bluejay.. you want em going fast.. i am not saying it cant be done, but its gunna require a special alloy, and will be prone to issues... the guy to talk to is Larry...

marko

[Larry Gibson]

Many times what we "want" and what we get are two different things. Yes, you can easily get 2400-2500 fps with a 180 gr cast bullet using 748 in the .308W. Getting any accuracy (precision) is another matter.

Would help if you told us what 180 gr cast bullet?
What rifle?
What length of barrel?
What twist?

[bluejay75]

The MP Molds 180 grain mold. The one that came as a 3 banger HP.
Savage 110
17 inch barrel
1:10

Any suggestions welcomed Larry. Even if it is to change powders.

[popper]

I've gotten 2400+ (170gr FP) from 16" 1:10 AR10 (LR308 carbine). With accuracy. It takes a harder alloy with 0.3-5% CU added. 3 shot just above MOA @ 200 good enough? Just playing with a friend in a field shooting steel.

[Ford SD]

The MP Molds 180 grain mold. The one that came as a 3 banger HP.
Savage 110
17 inch barrel
1:10


I have used W748 with cast in 308 many years ago... can not find data I used .... Used in a M1a Clone and a Sako

w748 with cast and 308 cost is a bit more than other powders as you use more. its a good powder as it measures well

RCBS Cast book has some 308 loads using W748
from the book for a rcbs 30-180-sp 36.0 = 1921 max 38.0 = 2023fps .... no pressures given

I would think the 36.0 load would be the max for the 10 twist

My favorite load was with SR4759 :( in the bolt gun Discontinued :(

[bluejay75]

I've gotten 2400+ (170gr FP) from 16" 1:10 AR10 (LR308 carbine). With accuracy. It takes a harder alloy with 0.3-5% CU added. 3 shot just above MOA @ 200 good enough? Just playing with a friend in a field shooting steel.


What powder good sir?

[Silvercreek Farmer]

What is your accuracy requirement?

[bluejay75]

What is your accuracy requirement?

I could live with 2 inches at 100

[wnc435]

Win 748 is funny powder it gets lazy when the temps rise the pressure falls off and gets violent when it's cold pressures rise. I have several older manuals that list loads for the 308. Just send me a PM and I'll send what I have.

[charlie b]

I also have a Savage .308, Model 12, 26" bbl and I have shot a bunch of the Lee 309-180 bullets in it. Powder coated and gas checks. Sized to .309.

This load was estimated to be around 2400fps (34gn of Varget has been measured at 2150fps, 32gn was 2000fps). I never fired that high a vel load again. It was just to prove to myself that the powder coated bullets would shoot ok at that velocity. That was 200yd so less than 2MOA (getting close to 1MOA).


262909

FWIW, I use Varget because of the temp stability.