I had tripped over this article a few days back, and then I got an email from Wideners. I make no money, nor do I receive anything for posting this. Subsonic 300 Blackout Ballistics - Field Trials
I have wanted to build a 300 Blackout AR since I first read about it. A heavy, slow-moving (relatively speaking) bullet out of an AR platform would seem to be what is called for when it comes to home defense. Now that the ATF has relented on suppressors (Ohio is still trying to get its act together) a subsonic 300 Blackout seems to be just what is wanted.
Many say shooting is a game of inches. This is true. But it can also be a game of silence and ballistic efficiency. In this article, our goal is to understand the finer details of subsonic 300 Blackout cartridges. We’ll compare different companies, different barrels, all at different distances.
It’s often tough to decide which rounds to test in these comparisons. So we selected options that cover a few different categories. The combinations of 300 BLK ammo and barrel lengths we tested gave us data that should be useful for a variety of gun owners.
I do love a good statistical study.
The one thing that has held me back is the thought of adding another caliber to my logistics chain. I have recently thought that 12 gauge should move to the forefront, and another part of me is considering .45 ACP in something suppressed. But, that all calls for more disposable income than I have right now. I just spent way too much money on repairs for my SUV, and tomorrow I get to rent a trencher to play in the mud, though it is more dirt than mud.
If any of you have experience with 300 Blackout, I would love to hear in the comments. The only thing I know for sure is that, depending on the barrel length, variable/adjustable gas block is required. I can't recall without digging for notes if direct gas impingement is OK, or if a piston is preferred.
Pistol length gas tube is required for sub sonics. You need longer dwell time for the heavier bullet and slightly lower pressures. A lighter buffer and spring can help but I never got reliable cycling with those and mid length tube. Maybe two rounds out of a cold barrel at best. Adjustable gas blocks can only reduce the gas flow from the fixed orifice in the barrel, so not the solution to this problem.
ReplyDeleteOne more thing. If you're building a home defense gun then you're probably looking at a pisiol or SBR so you've got a short tube anyway. An 8.5" barrel is LOUD. If you're suppressed and using a mid length tube then you may get enough pressure for cycling. Don't know for sure, haven't tried it.
DeleteThanks for the info. I'm not sure I will build something. My next project will be 556 Wylde, which I already have a barrel for, but never got the rest of the bits. Building the 1st AR was interesting, even if I want to tear it apart and replace some stuff. (Though chasing pins and springs around the basement was not fun)
DeleteBut lately I've been thinking I should just use a shotgun for home defense. Pluses and minuses.
Yep, back to basics. Just rack it hard.
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