AR-10SD

dustinm · Dec 28, 2013

Greetings,

I recently submitted my form 4 for a Gemtech Sandstorm TI 7.62 suppressor. Now the fun starts. I am starting the process of developing a subsonic round that works well in my AR-10. I have 9 months while the ATF processes the paperwork so I'm not in a big hurry (might take me that long to find a 1lb of Trailboss powder). Here is some of my concerns, if anyone has previous history with this I would welcome the help.

I want a round that has enough powder to cycle my AR, but not enough to create a sonic crack. I have read trailboss is the preferred powder, I should drill my flash holes to 9/64" and use magnum primers to ensure all the powder is ignited. I'm also very concerned about bullet tumble when it leaves my barrel into the silencer. I selected Hornady round nose 150gr bullets and hope to have this figured out before I screw on the silencer later in the year.

Lastly, accuracy. I kind of feel I want to have my cake and eat it too after reading a lot of posts. Anyone have tips for a new-be to the world of silent shooting?

Thanks!

rrojohnso · Jan 2, 2014

I have no experience with suppressors, but know you can get a variable gas block for your AR that can speed the cycling up (or slow it down). It may be something to think about when dialing in your set up.

Certaindeaf · Jan 2, 2014

Red Dot powder and "The Load".. people have been doing that for a very long time with that powder..

The Load

I mainly use The Load in my 30-06 with gas checked 195 grain slugs.

usagi · Jan 2, 2014

you are going to have to use HEAVY bullets to do it. better hope your barrel twist is up to the task.

why not just build a 300blk, it's designed from the ground up to run subsonic suppressed on an AR.

there is absolutely zero need for adjustable gas block when it comes to subsonics. with subsonics the problem is NEVER "too much gas". it is ALWAYS "not enough".

Certaindeaf · Jan 4, 2014

Do you have a chronograph? That's really the only way to know they're subsonic without a can. I don't know if the 150's will be heavy enough to cycle the action while remaining subsonic.. I really doubt it. Also, it really sucks to get a slug stuck in your bore, especially a jacketed one in a rifle.. work DOWN your loads.. within reason, and always check for stuck slugs and be prepared to beat one out.
I'd buy some heavier slugs (a box of 100) and see if they are accurate at low velocities.. probably 200 grainers and perhaps even the old and still available CoreLoct 220 grain RN Remington slug. Be aware though, the more bearing surface and the harder the jacket (some are monolithic and or bronze also) the more unforgiving (in a way) they are.. they are more prone to getting stuck and are harder to get out.
Good luck.