This will be my first AR. My main use for this will be killing the coons and coyotes that inevitably go after my chickens. The coop is about 100-120 yards depending on where I stand. As a secondary note I'm hoping to throw a different upper on it for a hog hunt next year. I have very little knowledge with this stuff and gained the vast majority of my information from the internet, so if I should use a different part please let me know.

M4E1 Stripped lower
Gisselle AR15 Mil-spec lower parts kit
Gisselle SSA-E (I already was given this part)
JP Enterprises AR-15 Low mass Bolt Carrier Assembly (The wife is recoil shy so I figure a little extra money spent here might be worth it as she does like going to the range with me.)

Aero Precision AR-15 stripped upper receiver
Superlative Arms Adjustable gas block
Vltor IMOD Modstock
Giselle rail ( I would definitely like more suggestions for rails)
Barrel? Ive seen a lot of people suggest Krieger Barrels But I feel like this might be overkill especially for a first AR. I could really use suggestions here.
Raptor-LT Ambidextrous Charging Handle (I was given this already)

For small game, id go with 1:12 barrel and use some varmint loads 49-50 gr ammo.

After 8 rifles and thousands of dollars chasing gimmicks and trendy parts my advice is.

Buy the cheapest m4 ish you can find.

Shoot it

Then start a personalized build.

Given your base platform, why not go with an aero complete upper (m4e1 or atlas r1)? BA barrels are gtg.  High value, rigid, accurate, durable, reliable.

Some suggestions:

Barrel: Ballistic Advantage Hanson profile or Faxon Gunner profiles are my favorite check them out.

Muzzle devise: VG6 (part of Aero Precision) best performance / value IMO.

Safety: Radian Talon, again best performance / value.

Handgaurds: I typically go with the Aero Precision M4E1 with the Gen 2 M-lok as there attachment design is super rigid but for a normal upper I like the Texas company STNGR. They are a good performance / value option as well as Midwest Industries (Combat rail).

Stocks / grips: Magpul makes everything one could need / want,  I’ve never found a different company’s products that would cause me to switch.

Optics: Primary Arms ACSS reticle options have been great for me, give them a look, your going to need glass right?

Sounds like you have a great build shaping up and hope this helps a bit. Don’t worry, after you get this one built you’ll think of some things you want to change and end up building a dozen...

They are like potato chips

This is the best site for info, be sure to check out the build guides and welcome aboard.

ETA: There are so many vendors out there it can be overwhelming. This is my GTG vendor list:

Primary Arms (optics, parts)
Schuyler Arms (builder sets, everything Aero)
Arm or Ally ( barrels, bcg)
Right to Bear ( barrels, bcg)
Wing Tactical ( specialty items)
WC Armory ( bcg )
Palmetto State Armory ( for certain deals)

Ditch the low mass carrier and get a Surefire Pro Comp.

Stick with a 1-7 twist barrel.

Cost.

For what your intended use is,  don't waste your money on an adjustable gas block especially on a .223/5.56. A standard block or barrel will do just fine. Use the money toward ammo or something else.

I would say that the low mass bcg is not needed, as there is very little recoil with the .225/5.56 round as it is and you can tune the standard bcg with proper buffer and spring with that adjustable gas block. If you really want a light weight bolt carrier I would get one from Right to bear or Aim surplus You could get a LaRue barrel, Ballistic Advantage Hanson barrel or get a Larue Ultimate Upper kit

As for rails it's more of personal choice on length, looks and need. If you wanted a cheaper rail you could look at ALG rails. I have a Geissele rail on my SBR and they are nice rails.

Get a Larue Barrel

Parts list is solid.

I personally would go with just a brake instead of a low mass carrier. You could put a dead air or Surefire brake on and be ready for when you get a suppressor.

I’ve never been a fan of vltor stocks but you can’t knock their durability.

Krieger is a lot of barrel for your first rifle. I prefer faxon gunner barrels but ballistic advantage Hanson barrels are good to. If you order from aim surplus these come with a pinned gas block. You don’t really need an adjustable gas block. You could just tune with springs/buffers or an adjustable carrier and have a factory pinned gas block.

In fact I’m in the deer stand and I just shot 2 hogs with my 7.62x39 AR that has a M4e1 upper/lower, geissele parts kit, faxon Gunner barrel, and dead Air Sandman S.

Make sure you get the M4e1 upper too to match
https://www.graniteridgeoutfitters.com/Aero-Precision-M4E1-Threaded-Assembled-Upper-Receiver-APAR700201AC.htm

Dead air muzzle brake
https://www.brownells.com/rifle-parts/muzzle-devices/compensators-amp-muzzle-brakes/sandman-keymount-muzzle-brakes-prod87181.aspx

Faxon 16” gunner barrel with pinned gas block
https://www.aimsurplus.com/product.aspx?item=XFX15A58M16NGQ&name=Faxon+Firearms+16+IN.+Gunner+.223%2f5.56+4150+QPQ+Nitride+Barrel&groupid=8945

Here’s my 7.62x39 AR I mentioned with a pig I killed this morning

It's a .223, for crying out loud........

The only time you should go with a low mass bolt carrier is if you shoot only one particular brand of ammo, and you're tuning the gun around that round's characteristics.  A gun that's going to be used from everything from a skunk or raccoon up to hog is required to operate properly off a broad range of ammo, from the cheapest stuff to the premium stuff.  Besides, .223 has little recoil, lesser recoil is perceived in a mid-length or rifle length gas system.

A 1:7 or 1:8 twist will stabilize anything that fits in the magazine.  If you want to shoot 80's and 90's, get a .224 Valkyrie

You would be fine with a standard common barrel. No reason to over spend on it.

I just placed the orders. This is what I ended up with.

M4E1 Stripped lower
Gisselle AR15 Mil-spec lower parts kit
Gisselle SSA-E (I already was given this part)
AIM Surplus AR/M16 .223/5.56 NiB 9310 MPI Bolt Carrier Group
M4E1 stripped upper receiver
Vltor IMOD Modstock
Aero Precision  Enhanced M-LOK Handguards, Gen 2
16" 5.56 BA Hanson Midlength AR 15 Barrel w/ Lo Pro, Performance Series (.625" Gas Block Journal) (1:7 twist)
Raptor-LT Ambidextrous Charging Handle (I was given this already)

Looks like a great build. I have that barrel. Last time I took it to the range I shot some .5 MOA 5 shot groups at 100 yards with handloads.