Subsonic bullet recommendation

[wscrst]

Thank you all very much for all the help. I have decided not to sell my rifle. I'll try the bullets and powders you have suggested and buy a chrono. Great stuff. Exciting.

[ozleux]

I've had some success with Lil Gun using everything from a 147 fmj to a 245 coated lead. All cycle in my gas guns. There are some really sharp people
on this site, with a lot of great info.

[dohalysh425]

I am about a month away from offering the heaviest cast bullet designed specifically for the 300 Blackout. It will be 270+ grains, Hi-Tek coated and function in an AR. Keep an eye out because as soon as they become available I will be posting details in the new product announcement section.

If you want quiet you really need a single shot because ARs are loud if they are cycling. I loaded up some of the 270+ yesterday with 5 grains of Trail Boss. It is a compressed load but it works perfectly in single shots and it is stupid quiet. I bet I have shot 50K rounds through silencers and the single shot loads ALWAYS make me giggle like a little school girl. And as an added bonus you will use less powder with my bullet and less powder means less gas and less gas means you gun will be quieter.

Did you chrony the load you shot with 5gr of compressed trailboss?

[hardcase]

I use the 220 gr PC coated bullets from a vendor on this site suppressed. Works in my carbine length 300 Black and pistol SBR using Reloder 7.

I would suggest putting the bullet in an empty case with no crimp, letting the bolt close, then measuring to get an idea where your load is off the lands making sure you are not slamming the bullet tight against the lands.

Also if you use recycled brass, get a Sheridan case gauge. Some of the brass available has thick neck walls and may require tweaking. Just sizing won't help if the neck wall is to thick. I had to discard a couple handfuls of brass for this reason.

I make sure my bullet diameter is no bigger than .311 and preferably .310.