Anybody reload sub-sonic .308Win

The simplest route would be to go with Trail Boss. Find out how much of it fits under a seated bullet without compression and 70% of that is your starting load. That's the published technique from IMR/Hodgdon themselves.
Could also try light loads of fast shotgun/pistol powders like Unique, 700x, etc. Usually 12-15gr will give semi-decent accuracy and often be subsonic. I use that a lot for really light loads with cast bullets.
 
Works just as well. I've used cast data for jacketed bullets on several occasions. Just make sure to use the same bullet weight.

The Hodgdon data site does have some subsonic load data for rifle rounds and they look very similar. For a 168gr HPBT they say to use 8.0gr of Titegroup or Clays for 1080fps and 1060fps respectively. Those are both pistol/shotgun powders.
I now realize my recommendation of 12-15gr of Unique would probably be super sonic so scratch that.
 
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Trail Boss is the ticket. I believe I was using around 9 or 10 grains of trail boss with 168's. Get a chrony and work around there.
Subs are a ton of fun.
 
I load subsonic for every caliber I own using Trail Boss (Hodgdon). The 45-70 and .350 Rem Mag have less recoil than a .243 Win. As noted, it works equally well for cast or jacketed bullets. For plinking out to 50 yards or so it's a lot of fun.
 
I made sub sonic ammo for 200 gr jacketed bullets in a canned 308 rifle. As I recall, I used around 8 gr of 2400. 2400 was good because it had no ignition issues.

If i was going to do it today, I would try TrailBoss, too.
 
I am thinking of trying 8grs of clays or tight group with a 168 SMK or 167 Lapua 200m primers and win brass for my 16" ruger scout


My worries is do I need filler?
 
Jamie said:
My worries is do I need filler?
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I've never used a filler with light loads of pistol/shotgun powder in large cases. Even cases as large as .300WM or .45-70. I do usually use magnum primers for these loads but haven't tried them without. I've never had a hang fire or problem without filler. Several others report hang fires or complete FTF's with light loads. Some say it's especially bad when shooting downhill (powder moves away from the primer?) or in cold weather. I'd say try it without and if there are issues, try it with. Or load up some of each if you already have dacron or something for the filler and try them both at the same time.

I tend to avoid the harder-to-ignite powders for these loads though. Things like H110/W296.
 
Jamie said:
I am thinking of trying 8grs of clays or tight group with a 168 SMK or 167 Lapua 200m primers and win brass for my 16" ruger scout


My worries is do I need filler?
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Yes worries. You should NEVER EVER go below about 40-50% load density. Even then I would seriously consider drilling out flash hole and use magnum primers to ensure proper ignition.

It is also important to lube bullets to prevent them sticking in the bore.
 
Suputin said:
Yes worries. You should NEVER EVER go below about 40-50% load density. Even then I would seriously consider drilling out flash hole and use magnum primers to ensure proper ignition.

It is also important to lube bullets to prevent them sticking in the bore.
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better tell everyone shooting 45 acp, 44 or 38 special to start lubing their bullets! But trailboss is great, fairly clean burning and great load density, never had any issue with anything thing sticking in the barrel though.
 
Suputin said:
Yes worries. You should NEVER EVER go below about 40-50% load density. Even then I would seriously consider drilling out flash hole and use magnum primers to ensure proper ignition.

It is also important to lube bullets to prevent them sticking in the bore.
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There is a risk of a double charge but I try to always use loads that, even if accidentally doubled, will fill the case enough to notice (at least to the shoulder) or wont blow up the rifle (but may stick a case). A subsonic load, even if doubled, wont be able to blow up a modern action. 8gr of pistol powders, doubled, is still a safe load in a .308. Tripled, you may start to get stuck cases and blown primers; not enough to detonate a modern rifle though. I've used 12-15gr of Titegroup and various other pistol powders for supersonic cast loads in a .308 and it's well below max pressure.
There is no laboratory evidence to support a SEE with fast powder; only anecdotes.

Larger flash holes actually decreases flame temperature in the case and makes the primer less effective. There is scientific data from ballistic laboratories supporting this. I've never drilled out a flash hole and have not had problems getting large cases with 10-15gr of pistol powder to ignite.

I've never lubed jacketed bullets and never had them stick unless I was doing something silly like trying to get a .44 magnum to go 500fps. I don't know where this idea of lubing jacketed bullets for subsonic comes from but the first time I saw it was on an Iraqveteran8888 YouTube video and it made me raise an eyebrow then. If the bullet is the correct diameter for the bore, there is no gap between the bullet and bore so how can any lube get in there to actually lubricate? It'll get pushed ahead of the bullet or stay behind. Some older military ammo was lubed but they had a groove in the jacket to hold the lube (WW2 era .303 British, 7.5x55 Swiss, etc.). Maybe if you crammed lube in the cannalure of a jacketed bullet it may do stay there but I don't know if it'll do anything.

I've heard of lube on the nose of a jacketed bullet decreasing pressure but I believe that's just within the throat.
 
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I've done up subsonic in 6-8 chamberings, including .308 win, using both cast and jacketed.

I use trail boss.

I have gone well below 50% load density, but with Dacron filler, in larger cases like 9.3 x 62.

Last time I read Trail Boss info from the manufacturer, they stated filler was not needed or recommended, but that is NOT the same as "Don't do it, it's dangerous".

I never drill flash holes.

I seem to recall 6 - 8 grains of trail boss in a .308 case with bullets from 165 - 200 grains. No filler needed. You can go more of course.

I've also loaded up to about 90% load density with 200 grain cast for a fun plinking load for destroying clays at 100 meters, and it works great.
 
j_06 said:
better tell everyone shooting 45 acp, 44 or 38 special to start lubing their bullets! But trailboss is great, fairly clean burning and great load density, never had any issue with anything thing sticking in the barrel though.
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In a long rifle barrel, a subsonic bullet can stick. I've had it happen twice. And I only ever had it happen on bullets I didn't lube.

Pistol bullets are an entirely different issue. Typically they are not shot out of a 24" barrel. Additionally they have a much shorter bearing surface than a long rifle bullet so generate less friction.
 
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