Have a Daniel Defense M4V1 that I've owned for a few years.. Put a fair amount of $$ in to a desert digital cerakote finish, new trigger, etc.. Realized the other day though that I'm just getting bored with the .223/5.56 round & got to thinking about what it would take to change calibers w/out changing uppers.. Perhaps moving to the 6.8 or 6.5?

Obviously need a new barrel & bolt, but is there anything else involved that I've overlooked? Buffer? I hate to try to sell it just to change calibers as I won't get near what I have in it back, & I like the work I've put in it..

Thoughts?

build a new upper for whatever caliber you want and keep 5.56, switching back and forth is a pain parts wise. start fresh with a new stripped upper, you can even get it coated to match the lower. my $.02

Don't know how well I could get the colors to match though.. What to do, what to do..

To change to 300BLK all you'll need is a barrel change.

To change to any other caliber that will fit the lower you'll need different mags, bolt, and barrel.

Swap barrels and slowly build another rifle with the .223 barrel

Shoot .223, cause it's the best in the AR.

^this.

.223 is probably the cheapest ammo to shoot unless maybe you do the 22LR conversion. 300blk would be the easiest and cheapest swap over. And it's a good round. An awesome round if you plan to suppress it.

I'd keep the 556 and just buy another upper in 6.8 if it were me

Rig it with your preferred glass and you're good to go.

6.8 is it!!!!!!!! Now the #2 most popular AR caliber, behind 5.56. Great hog and deer round.

Barrel, bolt, mag. I'd build another upper complete and swap um out. I've got 5.56 and 6.8.

The 6.8 is hard to beat.

Go for a blackout. Everything stays the same except the barrel. My Daniel defense m4v5 became a 300 black sbr and it's great.

What is your goal? (why has nobody asked that question?)

Do you want an SPR (long range)?

Do you want to hunt with it? Hunt what?

Any desire to SBR?

Desired barrel length?

If you want a 14.5-16" rifle, want a capable platform to shoot out to 600, kill deer at normal ranges? Go with 6.8 SPC (ar15performance is a GREAT place to pick up a barrel in this caliber if in stock).

If you want a dedicated long range platform 20+", capable of shooting 1k? .264LBC/6.5 Grendel

If you want to reuse all your 5.56 brass, enhance the hunting capability of the platform, use the same mags/bolt/everything but barrel? .300BLK. Moreso if you're thinking subsonic loads and a can.

Not entirely true.

If you reload there are other options. One being the 270 wolverine. Its a wildcat round but in the works for factory ammo.
It uses the 556/223 case and the 6.8 bullet. They are getting up to 2800fps with the 85gr pill. Producing about 90% of the 6.8 specs
Mad dog weapon systems is the developer and barrels are ARP. there's a ton of info on the 68forums about it. Only needs a barrel swap..uses regular pmags and 556 bolt

Build a new upper in 6x45. I doubt anyone will care whether your camo pattern matches.

Or start shooting 3 Gun. Then you will sell all your other goodies, and have more fun with what you keep.