What caliber will I be when I grow up??? Custom build thoughts.

So, working on my latest, “because I can build” and looking for input. Here’s what I have so far:

Aero Precision M4E1 upper and lower (really impressed with this pair)
LaRue MBT-2S trigger (love this thing!!)
Strike Industries enhanced LPK.
Magpul MAID grip
Magpul CRT stock (meh…)
BCM gunfighter mod 3 CH
Bravo Company Manufacturing A5 Intermediate Buffer System
BCM or Toolcraft BCG (about the same in my book and have one of each)

So, what am I missing, barrel of course which will determine caliber, muzzle device, handguard system (love Seekins, but would love to know some of your favs), and gas block/tube. Now here’s where I get the mental block, what caliber??? 5.56 and 9mm are out, have both of those covered several times over. Was thinking in this order, 300 Ham’r (don’t really hunt), 300 BLK (no plans on a suppressor, too many hoops) 6.8 (had one back in the day sold it, don’t remember why).

What say you, great wealth of knowledge and opinion?? Is there a favorite of yours that I’m overlooking? Barrel, caliber, handguard???

Thanks for the input and before anyone asks, I have built many and build my own 1911’s (a bit more tasking than an AR) and my budget for the missing pieces is about 500 or so.

What do you want to do with it? What part of the envelope would you like to stretch? Distance? Cheaper ammo?

There’s the rub, I simply don’t know… all the calibers I listed are always pricey and I have .22 covered 5 different ways. I was just wondering what other folks were digging and I was missing. Cost is not a major factor, but always a consideration.

This won’t fit your build…

But when I wanted more than 556, I settled on 6.5 creedmoore.

zero regrets.

I totally get that, but when I go to the AR-10 platform, I move to bolt guns. Weight and accuracy start taking over, before capacity and speed. Long range, seems I can be a little slower and methodical.

.50 BMG. The perfect all-around caliber - more than capable at CQB distances and out to 2+ miles LOL

hard to say what you should build, but i’ve always wanted a 6.5 grendel upper.

Build a 6mm ARC, it is a very accurate round and has some energy behind it. More accurate than a 6.5 Grendel, and their is a ton of different bullets available for loading if you reload. It cost me about .35 cpr to reload and thats at todays inflated prices. This round pretty much checks all the box’s, hunting, target, home defense. Even has ties to the military.

That’s one I hadn’t thought of! How does it stack against the 300 Ham’r?

That looks like a great round, but I’ve heard about feeding problems with it. I wonder if that’s just internet wizards spouting off what their friends might have heard. Not sure if the 300 Ham’r is a big improvement over it and the ammo is certainly more available and less expensive.

I’d go the 6mm route.

My suppressed AAC 300BO is my favorite gun to shoot.

What are some folks favorite handguards? I like the looks of the LaRue, but know nothing about them other than they normally make good stuff.

The BCM KMR is my favorite.

Any thoughts on the 350 legend?

What is it about 300 Ham’r that you like??

6mm ARC vs 300 Ham’r , not even comparable.

300 HAM’R just a jacked up 300 Blkout.

you have about 40-50 calibers to choose from.

https://en.wikipedia.org/wiki/List_of_AR_platform_cartridges

What does it do, that other calipers cant??
It was designed for some states with hunting restrictions.

What is the source for ARC being more accurate than Grendel?

That’s why I started this thread. I didn’t even know it existed. Looks VERY interesting!!

I have several 5.56, .22LR, and a 9mm SBR.

I personally debate .300BLK or .458 SOCOM but not enough to get myself off the fence. Is there a hole in your lineup. Say a DMR/precision 5.56 or…?