What Caliber

[ProBusiness]

I have a AR - Arfcom and lower says multi-caliber. i cannot find a caliber designation any where on the rifle. How do i tell what caliber the upper is?i have 223 56 bullets and the mag fits, it will cycle these bullets OK. I do not have any larger caliber bullets other than a .270

 

[Aries]

It should be stamped into the barrel somewhere? Maybe under the handguard? The upper and lower can both be used on various calibers, depending on the barrel.

 

[JEVapa]

Multi cal is the designation of the lower receiver. 99 out of 100 it's 5.56mm/.223. Look at the barrel up near the muzzle on top or on bottom
Something like this.

I'd add, where did you get it? paperwork or whomever you got it from should be able to tell you.

 

[rc508pir]

 

[jacobgh81]

Should be on the barrel somewhere. Possibly under the handguard.

 

[crispy]

sounds like one of them ghost guns i keep hearing about

 

[PBramble]

This guy has been here since 2009? I smell a troll thread.

 

[Bocephus123]

50 cal

 

[trbii]

You would think all legitimate firearms manufacturers, proud of their products, would have the caliber clearly roll marked, stamped into the steel. Not to mention the manufacturers name and the guns’ name or model number. Every AR platform I’ve seen that read “multi cal”, also read “5.56/.223”. I think that’s what “Wylde” chambers are. Longer “leade/throat ream”.

 

[AKguy1985]

Should be marked on the barrel.