Question on shooting subs and supers

[rhyned]

I'm just now getting my feet wet with the 300 Blackout. I've got a can on the way, but I want to get a few loads worked out before it gets here. Is there normally an issue with shooting subs and supers with the same setup? I was told the gas system was set up for subs. The gunsmith encouraged me to get an adjustable gas block due to supers being too much for the way it was set up. Also, would a Tubb carrier weight system and flat wire spring take the place of the adjustable gas block? Would this system cause a problem with the subs cycling properly? Sorry for so many questions, but this is my first AR in anything but .223. Thanks.

[tfbit]

Barrel length? Pistol or Carbine gas system?

If it's a 16" Carbine gas rifle then you cannot over gas it.

[rhyned]

It is a 16" carbine length. Am I correct that the size of the gas port coming out of the barrel can vary?

[tfbit]

Yes the gas port can vary but in the immortal words of an ex-Noveske employee, "you cannot over gas a 16" carbine gas Blackout". I have a DD 16" carbine gas barrel and have no problems with subs or supers. Only real use for an adjustable gas block would be to shut off the gas so the AR would not cycle (extra quiet mode) and to have another failure/maintenance point on your rifle.

See -k- reply here about what to do with the gas port on a 16" Carbine gas barrel:

viewtopic.php?f=136&t=81459&p=764202#p764202

It is a 16" carbine length. Am I correct that the size of the gas port coming out of the barrel can vary?

[rhyned]

Thanks for the information. How do you feel about the carrier weight system and flat wire spring? You foresee any negative effects from that?

[tfbit]

If you have a milspec bolt carrier I would suggest a C buffer as that's what AAC ships with their 16" rifles and what I run. If you have a commercial bolt carrier you may want to try an H1 buffer or play with the Tubb carrier weight system if you already own it. I personally prefer to use standard, easily sourced parts, in my rifles.

Thanks for the information. How do you feel about the carrier weight system and flat wire spring? You foresee any negative effects from that?

[rhyned]

I appreciate the help. Thanks.

[oneyeopn]

this is exactly what I was wondering, I built a 300blk using a DSA upper. I have been trying to decide whether to go with an adjustable or not gas block. I am going to free float the barrel and having to have access to the gas block to adjust it would be important.
Its a 16" with a carbine gas system, a T2 buffer, military-surplus bolt carrier. I have a box of Hornady 208gr Amax Subsonic factory ammo and a box of Remington Premier 125grOTM but after reading and studying before I had the gun built I was loading ammo for it, making my own brass.
I have loaded from 125gr Nosler Ballistic tip to 160gr Hornady FTX. I am building and loading this to be a recreational/hunting gun. I do not see any reason to shoot subsonic bullets, I have a 45lc leveraction for that. I cant see suppressing it, to much expense.
My brass for the most part is landing at 5:00, except for some 130gr bullets that I had loaded with 18gr of Lil'Gun that landed at 2:00 and my brass is all getting a little dent at the case mouth.
So do I need an adjustable gas block, would it serve any purpose.
Thank You Very Much.....heck where I am most of the shooters I know when I say I built a new rifle and tell them the caliber they go HUH?

p.s. I haven't shot the factory ammo....I can't believe the prices on it and so am hanging on to them to see if they really are made of gold!!

[certifiable]

Put some sticky Velcro (soft side) on the deflector.
Dented case mouths cured.

[45r]

The Tubb system goes 1.54 to 2.79 to 4.05 ounces in weight.
C=2.9,H=3.8,H2=4.6&H-3 =5.4 ounces usually.
3 o'clock ejection is optimal.
You can mix things up with the above and get smooth cycling tailored to the load.
Adding some weight works good for heavy loads and suppressed.
Works very well for big bore AR's.