Look on the barrel to find out.
.410
I don't know why someone would completely not answer you. You asked about the 600ct correct? So to know about the AT really isn't much use to you. Yes it is the same as the Mossberg 500A!!!!! It was a model created for a store brand to identify which chain was selling the item. All parts and fubctions and shape and size is identical to the 500A. The only difference is that it had a 1/2" shorter barrel than the 500A due to the full chokeAnswerThe Mossberg (New Haven) 600 AT is essentially the same as the Mossberg 500. The differences are the 500 has a firing pin spring, and the action bars on the 600 can only be removed by removing the magazine tube. AnswerThe Mossberg 600 AT is the same as the 500 with two differences. The 500 has a firing pin spring, and the action bars on the 600 can only be removed by removing the magazine tube.
Yes, the 600 At is the same model as the 500 series, but with a different designation for sale in New haven stores. So yes, all Mossberg 500 after market or OEM parts will fit it.
Do not attempt to use other than a Mossberg bolt made for that rifle.
6mm of either .12 or .20 gram bbs. 6mm of either .12 or .20 gram bbs.
THey use a shell
The road block shotgun you may be referring to is the Mossberg 500 "Road Blocker". It's a tactical use Mossberg released in 2009. Google "Mossberg Road Blocker".
It can be, if you are using a slug
With that size of load and a voltage of up to 300 or 600 volts, any extension cord can be used.
The Mossberg 500 Stock is the stock for the Mossberg 500 shotgun. The stock would allow you to get a better grip on the shotgun and absorb some recoil from firing the shotgun.
You could use any amp size over 100 watts for great sound production.
With that size of load and a voltage of up to 300 or 600 volts, any extension cord can be used.