6.8spc if you don't reload.

.300 BO if you do Reload. YMMV

Either one will work just fine. In fact 5.56 does fine on whitetail. I think proper ammo selection and shot placement are the most important factors. My 9yo daughter shot her first whitetail last season with her 5.56 AR and Federal Fusion rounds. It entered, penetrated both lungs and came to rest in the ribs on the far side. There was massive internal damage/clotting.

I think either round will do what you are looking for. If you are ever going to suppress the rifle, I would give the edge to the .300BLK.

As far as barrels, I like Krieger, Douglas, WOA, and Lothar Walther. I use several different triggers. I have had good luck with McCormick, Wilson Combat and Geissele.

6.8
bison 6.8 with vx3 and larue mount ( not in pic)

Nice shot that will make any dad proud.

I would look into Remington's .30 AR. Looks like a decent hunting close to medium range round for an AR.

Given that .223 is more than enough for a deer, you should be fine with either... so get both!

Since there's a thread going... I have been wanting to know what makes the .300 blackout better than 7.62X39? Do the bolt face and mags really out do the practice ammo price?

Yes. Can't beat a gun that runs with one that doesn't.

I actually intend to use 5.56 next time I hunt deer, but I think that characterizing .223 as "more than enough" for deer is unreasonable.

But then, I'm a cautious fellow when it comes to choosing hunting calibers.

Cautious you should be I saw 2 deer in my lifetime shot with 223/556 and neither one was recovered I guess if your going head or neck 223 will work.

I would rather have the 6.8 myself

.300 blackout fan boy here.

Figure the distance you plan on shooting. Less than 200, then the 300 blk will work very well in supersonic mode. Subsonic will be a little difficult, but can be done if you know range estimation and know the drop, but they may be moot if you live in a place where you cannot have a suppressor. advantage of same mags and bolt can save some money, but may not make a difference depending on what manufactures you go with.

Longer distance or not familiar with drop. then the 6.8 may be a better choice for you. And clearly it has taken down a lot of deer also.

As stated above I am a .300 blkout fan boy

I or my daughter have killed 8 deer with 300 blackout.

While I own a suppressor I cannot use it here in North Carolina for hunting YET? But there are some states that you can use one. For instance Virginia.
But notice all loadings but the one my Daughter shot were subsonic. I did this because I wanted to see for myself what it would take to take down a North Carolina white tail. That and reading post saying it cannot be done.

1st deer 2010 season 6 pointer missing an antler, neck shot drooped on the spot
178gr Amax
935fps






2nd Deer 2010 season 6 pointer did not get good pics of this one. Vitals shot bullet tumbled on exit. Made it 30 yds


entrance


Exit


Daughter took this one this year
180gr Prototype low velocity expander
1475fps


Exit wound

did a lot internal damage made it less than 50 yds

1st one for me this past season
200gr Prototype low velocity expander
935fps


entrance


found bullet just under skin on other side hit bone the whole way


serious spine damage


2nd one this past season


Entrance


Exit


Lungs


3rd one I actually thought was a large Doe, but ended up being a descent size button buck.

Right at the base of the neck and back. dropped where he was. he was still breathing a little when I got to him so finished him with my .22 1911 top of head.


recovered bullet in left shoulder.


4th one was another small doe a pair came in so I lined up one and took her in the shoulder. she ran off about 30yds and was dead.


Double lung shot
Entrance


Exit


Now the funny part was when I shot the other one of course took off the opposite direction then the one I shot. When I got to where I shot her I found this on the ground:

I was confused because I new where I had aimed and she was walking slowly when I took the shot, plus there was a blood trail. So I followed the blood and there she was. In just that few minutes, I had forgotten about the tail until I drug her back to where I shot her and then saw the tail on the ground again. I looked at her tail and the whole thing was there. I realized that as she was walking she had walked in front of the other one and when I took the shot the bullet went thru and then clipped off the tail of the other one.

Last one was a mercy kill spike buck came in limping and only one antler.


His back leg looked like it had been hit with a shotgun pellet. bone was shattered and had started to heal all messed up. wound was infected. the other antler which I thought maybe had broken off had actually never started growing. We have hunters that run dogs in this county and this is seen a lot. guy tries taking a shot at a running deer with his 12 gauge and all he does is wound it . I am not a fan of dog runners.

All in all a successful year. All six deer shot with .300 blackout recovered and processed. Meat in freezer and looking forward to next season.

It has become My go to hunting rifle.

Another one for 6.8.
(Look for SPC II (1:11, most have it now.)

It has the legs to reach out further & flatter than the blk.
But, if your into subsonic suppressor shooting, blk does a very good job.

Oh, johnysixgun, Yes, the .300 does better suppressed. Although, the blk is slower than the 7.63x39. It just needs a banana type clip. That was the big mag issue you have heard above.

Trigger, barrel stock & forearm, So many choices on them. Magpul stocks seems to be very popular. Triggers, what is your budget?
ARP & Bison makes very popular 6.8 barrels. Although, ARP, has their own 6.8 chamber& rifling design. But, there are many companies that sell 6.8 barrels/ upper to choice from.
Someone else will have to speak for 300blk barrel/uppers.

It's your choice.