Black Rifles AR Barrel question

[TheSwampFox]

I just ordered an AR barrel from sportsmansguide.com. They were finally back in stock and only $89.99 with the member discount. According to the site it is a 1/7 twist chambered in 5.56 but when it arrived there are no markings on the barrel at all and nothing on the packaging states what it is either. Is there an easy way to determine if it is indeed a 1/7 5.56 barrel?

I've never had any issues with sportsman guide in the past that would lead me to doubt what I have is anything different than what they say it is but I don't trust many people especially those who want my money.

 

[mch28]

This will help find twist rate http://www.youtube.com/watch?v=cdoCNZBlRGQ

You would probably need a chamber cast to determine between 5.56 and 223

 

[TheSwampFox]

Thanks for the video. That was a pretty simple solution. It is indeed a 1/7 twist.