Thread: 308 Subsonic powder alternative to Trailboss

Originally Posted by No.3

There's a lot of red dot about it seems, not sure about AS30 but yes they are very close in performance. I see it's in stock at Bronco's on the website where AS30n is listed as out of stock...

P.s. what length and twist is the black mountain barrel? That 10gr might be perfect for a faster twist barrel I'm thinking...

The black mountain is 26" and 13" twist
The twist rate has no real effect on the powder charge at low velocity
I tried 7.5 grs of AS30 yesterday velocity was still at 1200 fps with ES 39 SD 11 and a reasonable group at 50 metres
will be interesting to see how low the powder charge will go

Cheers for the info guys..
I had a little play around myself last week as I have some a few pistol powders and large pistol primers (as large rifle primers are the price of gold). Using AP350, Started at 9gr and worked my way down to 6.4gr until I got to 1070fps.(some precautions were taken) Tried 10 more and found Burn was clean and primers all looked ok and nothing out of the ordinary to report and speed range between 1049 -1072fps. Will try for accuracy soon.
There are probably a few alarm bells sounding off at the moment and if so moderators please delete this post if you feel im stepping out of bounds.
16 inch Bergara 1:8 rifle.

I use 452AA with a 220 grain bullet and no filler. Without going to check my book I can't be specific about the charge but it was about 12 grains for 1050 fps. I also use it in .300 Whisper.