I have been tinkering with loading up some sub 308 WIN for my 16" bolt and 12.7" LWRC R.E.P.R. (both 1 in 10)

Why?!? Because 'Merica...

I am looking for any load data.  I'm currently looking for Hodgdon CFE BLK using 208 Hornady ELD Match bullets data.  
I've already loaded some 168gn Trail Boss to test but can't find any data for CFE BLK.  I heard the Hornady 212 ELD-X will not stabilize with slower velocities.  
I should have some chrono on the 168 gn Trail Boss soon to list.

Please list any subsonic 308 WIN load data below.

Federal: FC 308 WIN cases
Powder: Trail Boss
Charge weight: 12.5 grains (this is NOT a compressed load; never compress TB)
Bullets: either the 210 grain Nosler RDF or the 220 grain Nosler CC (both bullets are about the same length @ 1.510")
Primer: CCI Large Rifle Primers (#200)
COAL: SAAMI length correction >>> (Magpul) AICS mag length (2.87")
Rifle: Bolt action, 20" barrel, 10" twist

For me, both bullets are subsonic and make nice round holes in the target at 50 & 100 yards.

Using a TBAC Ultra 9 (30 cal), the rig is hollywood/pellet gun quiet...     AND a ton of fun to shoot with essentially no recoil.  It draws attention at the range!

Using your shorter barrel, you should be able to get 180s to go subsonic pretty easily.  The 168s might be a little light.  Doing some of your own testing should tell you quickly...

At one point in my R&D, I tried Hornady Interlock 220 grain & 180 grain bullets and Speer 200 grain HotCor bullets - they worked just fine but I get better results with the Nosler bullets, and Nosler seconds (blems) on sale (when you can find them) are cheaper than the Hornady Interlocks or Speer HotCors.!

Thanks Reorx!  Exactly the info I was looking for.
Great info in your post. I look forward to trying out some of those loads.

Any experience with any other powders?  I’ve heard the Trail Boss is dirty. I’ll find out this weekend if I can get away and fire my test rounds.

No, I don't have any experience with other powders to create subsonic loads for 308.  IIRC, some folks use VV N32C (Tin Star) to produce reduced loads - you might try searching it...  It is supposed to be pretty clean burning.  Although, I must say that I pay essentially no attention to how dirty TB may be - I don't shoot all that many sub-sonic rounds but haven't noticed any excessive carbon problems when I do...  For me, subsonic 308 is a "special purpose" round...

@HighpowerRifleBrony is fond of using Tin Star for reduced loads although he uses lighter bullets and goes supersonic...  He has several threads around here on this topic...  THIS is one of them.

Now that Hornady is selling the 190 grain subs that's for the 300 BO, should work good for 308 subs.

Good call Bearcat24!  I’ll be sure to try these out.
Hornady Sub-x 30 cal per their description they expand starting at 900 FPS.

I made it to the range and tried out my new LabRadar. Awesome piece of equipment. Of course it was 17° and with the windchill we’ll below zero. I only shot 15 rounds and called it. Never made it to my sub rounds.

Rem 700 ACC SD 20" bbl  1-10" twist  and running a Sig SRD-762 Ti can.

cast 170 gr RN bullet
7.2 gr Trail boss
1017 fps  avg

Sierra  180 RN SGK
10 gr Trail boss
1025 fps avg

Leatherhead  220 gr RN coated
9 gr Trail boss
996 fps avg

The 168gr BTHP bullet is probably the worst possible choice for subsonics.  This style of bullet has a fat bum and a long nose which makes it the most difficult shape to stabilize at low velocity.  Ether go lighter with a 147-150gr FMJ or heavier to around 200gr.

For just plinking, the 150gr bullet is the best choice.  They are considerably cheaper than the heavier bullets.

With subsonic 308 it is VERY IMPORTANT to ensure every round leaves the barrel.  Dirty barrels and longer barrels can result in the bullet not making it out the end.  Shooting a second round into the back of a stuck bullet is ........ BAD

Tagged

I have gone up to 12.5 grains Trail Boss with winchester brass and a 200 grain Speer flat base spitzer soft pooint.

It stabuilizes well in a 1-10 twist and hodls up to 300 yards but I am getting about 90 fps ES on velocity which makes a big difference in poi at long range.

It is a really dirty powder esp if you are using a suppressor.  A pain to clean.  Lower velocity down to 11.0 grains noticibly more quiet.

I tried several primers and the Remington gave me lower ES.

I use 8.3 gr of TrailBoss with WLR primers, and 147gr FMJ pulled from crappy Turkish ammo.

IIRC, it clocked around 1000 out of a 16" barrel.  That wasn't in the winter, though.

Magnum primers can help to more consistently ignite the powder.  Another trick specific to subsonics in larger cases is to drill the flash hole out considerably larger.  The caveat to that being those cases can only be used for subsonics as they will no longer handle the pressure of a conventional load.

First Post

Case: Lake City 7.62x51 once fired in my rifle. Shoulder bump .002"
Bullet: 220gr Sierra Pro Hunter RN (MFG Part #2180)
Powder: Trail Boss
Charge Weight: 13.7 grains
Primer: Federal 210
COAL: 2.775" In my investigation, this is just about touching the powder without actually compressing it at all. This is about .096" jump in my chamber.
Medium Crimp (through initial load development, my SDs were lower with a crimp as opposed to without)
Rifle: Bolt action, 20" barrel, 1:10 twist

In my rifle, this produces a MV of 1,074 fps (magnetospeed) with a SD in the single digits and about 1 MOA accuracy.