Thread: Help needed for 308 subsonic load

Hi guys
I am new for reloading. right now trying to load a subsonic & supersonic 308 for my rifle in 1:8 twist, 16"
currently for the subsonic i am thinking about:

Sierra #2180 220GR RN,
Trail Boss
and maybe mag primer?

and have no idea for the supersonic

is there anything need to be ajust?

much appreciated for any advice or help.

PS. sorry for the poor English.

308 winchester

2208 is a good powder for the heavier weight projectiles. (supersonic)

If you are wanting expansion the 220gr won't at subsonic velocity. If you want expansion either get some 151gr hp cast projectiles from shooternz off here or spend $3 a projectile and get some Lehigh controlled fracture 168gr, I think Dean Maisey has them.
If you are going to stick with the 220gr start at about 12ish grain trailboss and work down until they go subsonic.

What @stug said. I've tried those bullets and they will pencil through whatever they hit. Fine for target shooting and plinking but not for hunting.

Long bearing surface on them too - more friction means more powder needed to get them moving. My load from a 20" 1:10 twist Howa was 13.2gr of Trail Boss.

Start with a nearly full case and work down, to ensure they have enough energy to exit the barrel. There's a bit of guesswork involved with subs and if you do it the traditional way that you would with supersonic rounds (start low and work up) and misjudge your start point, you risk getting one stuck in the bore. Saw someone at a gunsmith a few weeks back who'd done just that - gunsmith was happy to take their money to sort it out.

Originally Posted by stug

If you are wanting expansion the 220gr won't at subsonic velocity. If you want expansion either get some 151gr hp cast projectiles from shooternz off here or spend $3 a projectile and get some Lehigh controlled fracture 168gr, I think Dean Maisey has them.
If you are going to stick with the 220gr start at about 12ish grain trailboss and work down until they go subsonic.

Its 1:8 twist too fast for 151gr cast? Making the bullet fly apart?the reason why I choose 220gr is purely based on the fast twist. Would not 1:10 1:12 much suitable for 151gr?

Originally Posted by veitnamcam

2208 is a good powder for the heavier weight projectiles. (supersonic)

Thank you ! Will do some research now.

Originally Posted by PommyMcPomFace

What @stug said. I've tried those bullets and they will pencil through whatever they hit. Fine for target shooting and plinking but not for hunting.

Long bearing surface on them too - more friction means more powder needed to get them moving. My load from a 20" 1:10 twist Howa was 13.2gr of Trail Boss.

Start with a nearly full case and work down, to ensure they have enough energy to exit the barrel. There's a bit of guesswork involved with subs and if you do it the traditional way that you would with supersonic rounds (start low and work up) and misjudge your start point, you risk getting one stuck in the bore. Saw someone at a gunsmith a few weeks back who'd done just that - gunsmith was happy to take their money to sort it out.

Thank you! Fingers crossed I don’t need to visit a gunsmith

I think @shooternz is making 220gr casts too.
Loaded his 151 hps in 3 different 308s and 2 30-30s from 950fps to 1650fps and they all worked well.
No need to use Magnum primers with Trailboss.
Grab yourself a LEE factory crimp die if you don't already have one, makes crimping easier.

Originally Posted by lmlalong

Its 1:8 twist too fast for 151gr cast? Making the bullet fly apart?the reason why I choose 220gr is purely based on the fast twist. Would not 1:10 1:12 much suitable for 151gr?

It wont get anywhere near enough rpm to fly apart at subsonic speeds.

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you will end up somewhere between 8 and 6 grns of trailboss behind those 151s.....in the .308 they are good,very good think a .22lr power point subsonic but 5x bigger/heavier cause that is pretty much what you get.

I use 8.5g trail boss and either 151g or 170g cast Bullets,the 151g are a hollow point and expands a little the 170g just pencil on thru,only really good for small game at subsonic speed .

Originally Posted by The bomb

I use 8.5g trail boss and either 151g or 170g cast Bullets,the 151g are a hollow point and expands a little the 170g just pencil on thru,only really good for small game at subsonic speed .

8.5 grains of Trailboss had the 151s going at 1168fps in my 308, so still supersonic, I had to go below 8 grains to be subsonic.

I'm running 7.1 gn trailboss for the 151 hp, gives 1025 fps at 15deg C, remember that's for my dies.
I'm running a 1:8 twist.
Get a chrony, it saves guess work and heart ache. If you're in the BOP happy to lend you mine.
If you hunt deer, get some lehighs from dean maisey.
Good luck.

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Originally Posted by Boar Freak

I think @shooternz is making 220gr casts too.
Loaded his 151 hps in 3 different 308s and 2 30-30s from 950fps to 1650fps and they all worked well.
No need to use Magnum primers with Trailboss.
Grab yourself a LEE factory crimp die if you don't already have one, makes crimping easier.

Boar Freak, do you crimp the 151hps from shooternz? I got my first batch the other day. They work in my standard seating die, BUT I can push the projectile back by hand ones seated....

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