22lr to 5.56

[tws3b2]

I see a ar 15 5.56 can be converted to 22lr.
But, can ar 15 22lr be converted to 5.56?
I have no intention. Just wondering.

 

[Mk-211]

If it uses a standard AR15 lower, yes.

You can go all the way up to 50 BMG on a AR15 lower.

McCutchen Firearms MF-50M 5-Round, Mag-Fed, Bolt-Action .50 BMG Upper Receiver for AR-15 Rifles

McCutchen Firearms' MF-50M is a strong, durable, accurate, bolt-action .50 BMG upper receiver for AR-15 lowers. Made in the USA from the highest quality materials and with unsurpassed engineering.

www.mccutchenfirearms.com

 

[tws3b2]

So all you need is a 5.56 carrier bolt?

 

[Mk-211]

Depending on the caliber, you may need a BCG strong enough. Along with a bolt of the proper diameter for the caliber.

That's why it's important to buy a BCG matched with the upper, for the caliber you want.

 

[Mk-211]

You could probably find one cheaper, depending on what you want. This upper is from CMMG and comes complete.

https://cmmg.com/upper-group-banshee-mk4-22lr-9

Need more POWER?!

Tromix makes some powerhouse uppers.

.458 SOCOM Complete Assembled Upper – Right Hand - Tromix Lead Delivery Systems

As of April 2024, allow 5-10 days for this item to be built and shipped. Ready to fire on your lower receiver. Available in Black 4150 chromoly steel or 416 Stainless steel options. Base model includes a 6061 M4 style upper receiver, black 4150 chromoly barrel, black flash hider, black gas...

tromix.com

There are cheaper versions out there, always ask around before buying.

And there's even a beltfed upper.

MCR® DUAL-FEED™ UPPER (MCR-5.56 DFR)

Our groundbreaking MCR® (Mission Configurable Rifle) belt-fed upper receiver assembly is designed to interchange with standard AR/M4 type uppers and readily fits any MIL-Spec lower receiver without permanent modification to the host lower, and is rearward compatible to AR15/M16 models produced...

fightlite.com

 

[tws3b2]

No intention of doing it. But converting ar 22lr to 5.56. Absolute minimum needed?

 

[gotboostvr]

No intention of doing it. But converting ar 22lr to 5.56. Absolute minimum needed?

It depends.

Most dedicated 22lr AR's use a 22lr chambered barrel and no gas system.

Going from 5.56 to 22lr you can utilize a drop in conversion bolt.

Going from 22lr to 5.56 you'd most likely need a barrel, gas block and tube, bolt carrier group and probably a buffer and spring.

That's assuming they used a standard upper, lower, buffer tube and barrel nut.

 

[Mk-211]

As gotboostvr pointed out, you would basically need an entirely new rifle.

Here's what the BCG/bolt adapter looks like for a regular AR upper. Notice it has the shape of a .223/556 round for the chamber.



Here's a dedicated .22 upper and bolt carrier. Notice the ejection port, BCG are all smaller in size.

 

[bfoosh006]

It depends.

Most dedicated 22lr AR's use a 22lr chambered barrel and no gas system.

Going from 5.56 to 22lr you can utilize a drop in conversion bolt.

Going from 22lr to 5.56 you'd most likely need a barrel, gas block and tube, bolt carrier group and probably a buffer and spring.

That's assuming they used a standard upper, lower, buffer tube and barrel nut.

And magazines. ( Not trying to be a smart ass , just making it clear for the OP )

 

[gotboostvr]

And magazines.

I just assumed that was a given

 

[CapnMac]

So all you need is a 5.56 carrier bolt?

Actually, a complete upper is likely wanted, depending on whether the lower has a buffer or not (not really needed for 22lr)

Now, a home-built lower fitted to a 22lr upper might have the buffer tube, and it would just be empty. Then, you'd need the spring & buffer elements (and, potentially, the dread buffer detent).

 

[Varminterror]

Is anyone actually selling complete rifles which are true AR-15’s which have 22LR conversions? Most 22LR rifles sold from factory are really look-alikes, not actual AR-15’s, and have no road to be converted to an actual AR-15.