I have had an opposite experience at the local gun shop with a SU16 with an adjustable stock. The thing was so tight that it took great force to move it from position to position.
You may want to measure your tube and the hole in the stock. I'm not sure what tube diameter they use, probably mil spec. Really, it's nothing to get too bent out of shape about. My AR15 has the same thing with a mil spec tube and matching Magpul MOE stock, it's a little loose. Many other budget AR15's like the DPMS's and Deltons have this little amount of play in the stock. If it does bother you a lot, try upgrading the stock to one with a retention lever to take the play out of the stock like the Magpul CTR stock.
You may want to measure your tube and the hole in the stock. I'm not sure what tube diameter they use, probably mil spec. Really, it's nothing to get too bent out of shape about. My AR15 has the same thing with a mil spec tube and matching Magpul MOE stock, it's a little loose. Many other budget AR15's like the DPMS's and Deltons have this little amount of play in the stock. If it does bother you a lot, try upgrading the stock to one with a retention lever to take the play out of the stock like the Magpul CTR stock.
