Opinions on this .308 subsonic Youtube video

[TRD1911]

I'm looking for some insight into a couple of the techniques used in this video. Specifically opening up the flash holes (seen at 3:20) and using Crisco as bullet lube (seen at 11:20) to reduce friction at lower velocities. I am tracking on the rest that he mentioned throughout the video and much of this information matches up with what I've read in other subsonic threads (suggested powders, grain weights, load work-up...). I've read a few threads where guys have opened up the flash holes but can't find a thread debating the benefits before I dedicate a couple hundred good pieces of brass to this.

Also, I think that I know the answer to this already but have to ask. Over time, wouldn't the Crisco reduce the effectiveness of the powder? Can this be substituted with case lube (imperial?). Those that shoot subsonic frequently; Have you found lube/molly necessary?

Thanks for the help.

 

[Huckleberry75]

You do not have to open up the flash holes to sucessfully shoot SS. If you do decide to open them up, make dang sure you have a fool proof marking system to keep them out of full power loads, or you will see all sorts of pressure issues.

I typically run 12.2gns of Trailboss with 220gn RN in LC brass and about any LR primer. No molly, no nuttin.

12.5gns with a 208amax is pretty accurate as well, but borders in the sound barrier.

 

[TRD1911]

Thanks for the advice. I'll make sure to do a Sharpie job on them if I try them out. Once I get the chance it would be fun to do a side by side with a set that is factory and another with opened flash holes. I think I'll have to stick to the 175-180gr range (1-12 twist).