Hello Im new to the AR15 platform and I recently traded my CA VZ 2008 w/folding stock and Mako Quad Rails installed for this AR15

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I can verify that its a Spikes Tactical Lower (easily distinguished) and the stock is a Magpul CBR. What I cannot identify is the barrel and the upper. I was told its a Stainless Steel Barrel on a Free Float system? and I assume that is good from my research but what I really care about is, is it Mil-Spec?

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I have done my first field strip and it was really easy, im planning on doing a complete take down this coming weekend. I couldnt find any markings to indicate the caliber, I was told it runs 556/223 but I would like to verify this before taking her to the range. Also is there any other way to identify the caliber besides barrel casting? Any assistance this new AR user can get would be greatly appreciated.


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and here's the rifle [CA VZ 2008] I traded to get the AR15, do you think it was a good trade?

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It should be stamped on the barrel the brand and Caliber. With all the different companys using the few forgeing companys that are out there, its hard to tell who made the upper unless they have a company logo stamped or printed.

That leads me to believe I will need to remove the rails to get a better inspection of the entire barrel. I was hoping I didn't have to go that far.

After watching a video,on dissembling the free float rails, I realized I don't have the proper equipment at this time. I did notice in the video I was watching the barrel was stamped under the barrel nut. For sake of time I'm going to take her to my local gunsmith for a professional inspection prior to our first date at the range

Looks like a UTG rail. Keyhole forge made the upper receiver. Who sold it after that is anyone guess. Btw the rear sight is on backwards.

ETA: if mil-spec is what you are after that upper is far from it. Not that there's anything wrong with it, but you won't be finding a NSN for a bright stainless 16" barrel.

THANKS for sharing your knowledge! and I will fix that rear site ASAP!