Anyone reload subsonic .308 here?

[Chris C]

I have been doing research on subsonic .308 ammo and have some of the Hornady 170gr FP Interlock bullets designed for the 30-30 that I would like to use.  I have read a hand full of threads where people have had luck with this bullet with 1:10 and even some have used it in 1:12 twist barrels (quote below was 1:12 twist 22‘’ barrel).  All the data is pretty much close to the quote below from AR-15.com.  Only variance I have seen is the grain from 10.0 to 10.9.  Also have not seen any other COAL numbers.   

170gr Hornady FP Interlock bullet
10.2gr Trailboss Powder
FGMM Large Rifle Primer
2x or 3x FGMM case
COAL I think is 2.570(will have to check when I get home, on vacation right now)

The rifle I am using is a Remington 700 AAC-SD with 1:10 twist 20’’ heavy barrel and a Gemtech Sandstorm suppressor.  With the help of a friend I will be sighting this rifle in and maybe trying some hand loads once it warms up.  Would be nice to get a subsonic starting load to see if they function properly and that there is no key holing before trying the suppressor. 

Anyone see anything wrong with the above load data or have any other subsonic .308 load data? 

Thanks!

[bkoenig]

I'm interested also.  I have the same rifle but with a Form 1 suppressor.  I shoot subsonic cast 240gr bullets through this can with my 300 Blackout, but I'm guessing 1:10 isn't quite fast enough for that long of a bullet.

I've read a lot about using Trailboss for subsonic .308, so I'm thinking that's the way to go.

[sparky0068]

Is 5744 an option?

[bkoenig]

I bet that would work well too.  I know it works really well for light 45-70 loads, so it doesn't seem to mind a partially filled case.  It's dirty stuff, though.

Ran across this:

http://www.quarterbore.net/forums/showthread.php?t=280

[Chris C]

I loaded two cartridges up the other day at the 2.570 COL one with 10.8 grains and the other 10.5 grains with Trail Boss.  Test fired them at the bullet hole and both functioned fine and no bullet stuck in the barrel.  Only abnormal thing  I noticed (being a nOOb to reloading didn't know if it was a big deal) using these specs was the cannelure ring was above the case neck.  Going to do some more in 10.5 grains and 10.2 grains to see how they perform once I can get this sighted in. 

[bkoenig]

The cannelure being above the case neck isn't a problem.  I don't crimp my .308 loads so even if I was shooting bullets with a cannelure I would still seat them out as far as I can.  Unfortunately the throat is long enough on these rifles that you can't get the bullet close to the lands and still feed through the magazine.

Do you have a chronograph?  That's something you'll want to pick up if you're loading subsonic, so you can tweak the load to be just under the speed of sound. 

[Chris C]

I don’t have a chronograph yet but was looking at the CED M2.  I like the fact that the computer portion is separate, it comes with a tripod, and if in the event you shoot part of the chronograph you can buy the parts separate.  Still researching at the moment though. 

[SemperFiGuy]

in the event you shoot part of the chronograph you can buy the parts separate.

Shoot parts of the chronograph???!!!

Just can't imagine that that kinda thing would ever happen.
[Except maybe the skyscreens or maybe the skyscreen legs now and then...........]


Heck, what I do is just put the skyscreen legs on the vise anvil and beat them back into shape with a................         Never mind.

Shoot parts of the chronograph???!!!

Redickless!!!!

How could it ever happen??

sfg

[Chris C]

Ok I can’t tell if that is sarcasm or if you are serious the way you typed that out. 

Either way doing research reading reviews and threads on different forums I have seen that brought up multiple times.  Most of the time it is mentioned as a selling point for buying a chronograph with a separate computer portion not one that is a whole self contained unit.  I also saw it mentioned where something went wrong with a guys reload and the bullet ended up striking the unit.  Either way it was an interesting point and does make sense somewhat. 

[bkoenig]

Oh, it happens.  To a lot of people.  I'm always paranoid about shooting my chrony.  I set it up, look through the scope to verify, then look through the bore (if I can) to make sure I'm taking sight offset into account, then check the scope again, then the bore, then fret about still somehow screwing it up until I finally bite my lip and squeeze off a shot.

[bkoenig]

Just to egg you on, here's a video I ran across tonight:



I really need to try some subs out of mine.