Subsonic 308 loads?

[Hubbard]

I have been researching subsonic loads and have been getting mixed reviews.

I am looking for a stable and safe subsonic 308 load... no baffle strikes

How does this sound...
Powder: Trail Boss 10-11 grains
Brass: mixed
Primer: GMM or Winchester
Bullet: 200 grain sierra HPBT

Thanks for your input

 

[malaga2]

Re: Subsonic 308 loads?

Twist rate and length of barrel? I would look to 170/180 grn round nosed bullets for sub usage. Need info on the rifle !!!

 

[Hubbard]

Re: Subsonic 308 loads?

20 inch 1:12

 

[ChadTRG42]

Re: Subsonic 308 loads?

The HPBT would be questionable for a 175, so I would not think the 200 would stabilize. But, you could try a few with the can off and see.
I would look at the 180 SP flat base. Flat base are easier to stabilize.

 

[ggarrett1911]

Re: Subsonic 308 loads?

Try 10 gr Trailboss & 170 gr Hornady flat point (30-30 bullet), been a great subsonic hunting load for me. The 180 gr round nose may be a hair more accurate, but the 170 hits a lot harder. I don't think the 1-12 twist will stabilize a 200 gr bullet (especially at subsonic velocities). You might even try some of the 150 gr 30-30 style bullets as well. Good luck and remember to load 'em stout and work down with the powder charge so ya don't stick a bullet in the barrel!

 

[Hubbard]

Re: Subsonic 308 loads?

I am not planning on using fillers. What are the dangers involved with loading reduced rounds?

 

[malaga2]

Re: Subsonic 308 loads?

In looking at the thread again I would advise use of mag primers. the loading of Subsonic ammo is not for the novice reloader...
You risk having a bullet sticking in the barrel.. or worse the suppressor. Baffle strikes can ruin your can...
Pulled from another thread :

The ultimate danger in subsonic loading is a phenomenon known as Secondary Explosive Effect (SEE). SEE can destroy the strongest rifle action and it can happen on the first shot or the tenth. In fact it is more likely to happen after the bore is dirty from the first few shots. SEE is the result of slow or incomplete ignition of small amounts of smokeless powder. The powder smolders and releases explosive gases which, when finally ignited, detonate in a high order explosion. The warning sign for imminent SEE is a hangfire or delayed ignition.

There are a number of techniques that can be used to prevent or delay the onset of SEE. These involve specially prepared cases as well as bullets, in addition to selecting a suitable powder and primer.

Using Trailboss and mag primers will help minimize this concern. Some guys are also using Unique (did some 30/30 loads with this powder) and this powder was also used by TTI Armory in their sub loads.