5.56 or 300blk AR pistol?

Tgunz64

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Kind of torn between these 2 calibers for an AR pistol. Neither gun will be for hunting. Target/home defense/ all around fun. Which would you go with? I know if I wanted to hunt the 300 supersonic Ammo would work out to 100-150 yards decently. But since it’s not a concern is it worth having the 300? For defense obviously more stopping power. But just looking for other opinions. Thanks.
 

tbird86

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Do you already have a stash of 5.56 ammo? Any concerns about someone in the house mixing up the two magazines?

In general, at pistol length my vote is 300BLK. The cartridge is designed for SBR applications, and the unsuppressed noise/flash factor is much lower than 5.56. 300 subsonic suppressed is stupid quiet - nearly hearing safe.

If you have a suppressor rated for short-barreled 5.56, and plan to run it the majority of the time, I'd say it's a toss-up.
 

Tgunz64

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I have 223/556 Ammo but having a new caliber to buy Ammo for isn’t a problem. I know 300 will suppress better. Maybe I’ll go with the 300. I have my first suppressor in jail but it’s a TBAC 6.5 ultra 7. So I’d have to get a new one which I’m planning on anyway. Probably an Omega. Wish I would have bought the omega first. Oh well.
 

dogbuster0006

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5.56 in a short barrel is quite anemic, the muzzle blast is abusive unless running a Noveske pig style device or one that directs all blast away from you. I've shot a few and it only takes being near one at the range to appreciate the nonsense of having a pistol length 5.56.
300blk was designed to be in a short barrel 9" I believe was the original idea and it excels with super or sub ammo. I've shot one both with and without cans, both sub and super ammo. For home defense 50yd max work think of one with sub ammo as a 45acp carbine wth 25 rounds on tap, ballistics very similar. Bullet weight and energy wise bullet design is another argument entirely. I'm not going to argue ballistics and all that there's plenty of info on that already. 180-220gr bullets at roughly 1000fps and no one argues with the stopping power of 45acp at normal handgun range.
Being able to throw a mag of super sonic to reach out to say 200yd using a red dot you've got a short barreled carbine/pistol with more punch than 5.56 at all ranges. I'm saving up for a similar build myself with it primarily being a truck/barn/house gun with a mini red dot enabling me to quickly react out to 50yd and stomp racoons/coyotes/"other associated vermin" which I regularly see without waking the neighbors/my dogs/wife once suppressed.
 

budlight

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9 inches is the best length. try and find an 8 twist if you shoot very few heavy subs. I shoot cheaply with the blackout. Midway or midsouth shooters supply sells 500 box of speer 125 grain TNT frangible bullets. I also use them in an AR-10 308.

I use the smaller 3 mil dot. 125gr speer on a rest I can put 20 rounds into sub 5 inches. with a scope you might get down a lot further.

The muzzle blast of 5.56 in pistols is bad. When shooting with a can It will ruin the packing in a suppressor from the still burning powder
 

Axl

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9 inches is the best length. try and find an 8 twist if you shoot very few heavy subs. I shoot cheaply with the blackout. Midway or midsouth shooters supply sells 500 box of speer 125 grain TNT frangible bullets. I also use them in an AR-10 308.

I use the smaller 3 mil dot. 125gr speer on a rest I can put 20 rounds into sub 5 inches. with a scope you might get down a lot further.

The muzzle blast of 5.56 in pistols is bad. When shooting with a can It will ruin the packing in a suppressor from the still burning powder
There are plenty of Suppressors with Titanium and or Inconel internals. A stainless steel barrel will melt at 2750f Titanium melts at 3040f.
The Surefire SOCOM556-SB2 is rated 5.56 Full Auto with a 7" barrel there are others just need to match your equipment based on the MFG. rating
 
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