tippmann a5 stock thread

Ok so i bought my a5 from a dude and it came with the flatline. BUT it didnt come with the stock thread. Liek the adapter that come son it when you originally buy it. So i bought an adapter on ebay from a trusted seller. When i put in the adapter it appeared VERY loose. I even unscrewed the two screws above and below the barrel and then screwed them in tightly and no use. When i have the adapter and a barrel on it its wobbly, like out of control wobbly. My question is, is there something im missing? Or is there a way i can make it tighter. I plan on getting a 3 inch barrel so i kinda need this adapter to work out. Any suggestions?

There is an O-ring that fits inside the adapter. It helps keep the barrels from unscrewing. Make sure you have the barrel adapter in correctly. The typical way to remove it is to loosen the two receiver screws, twist the barrel and adapter counterclockwise and pull it out. If you are putting it back in, make sure you are pushing it in, turning it clockwise until it locks into place and then tighten the receiver screws back. If you have done this and it is still loose A) make sure the adapter was new. If it was used, it could have worn down.B) make sure the receiver halves aren't worn down from removing the adapter. In either instance, if you are installing it correctly and the receiver halves are worn, electrical tape or black hockey tape can help take up the slack.

ok well i put an o-ring on it and it wouldnt even fit in the gun itself. But i got an idea so i'll tell ya if it works

the o-ring is inside the adapter, not outside.