No.
No It uses a screw on the top that goes into the a5, the bt4 uses a rail system. Besides the Bt-4 already comes with a better hand-grip then the A5.
No, they will not both fit unless you have it custom fitted.
No. Hoppers meant for the cyclone feed will only fit the cyclone feed.
Any stock built for the Tippmann 98 series, including the project salvo, alpha black and the non Tippmann BT4. A5/x7 ans spyder mr stocks will not fit.
No it will not. the Handguard on the barrel is in the way of the handguard on the shroud.
No, you can not fit a double trigger in any of the US Army tippmanns.
Yes. Any scope or attachment with picatinny rail mounts will fit onto the X7.
As far as i know there is no markers specified for sniping in paintball. That's sorta reserved for airsoft. But a Tippmann marker with a flatline (X-7 or A-5 preferably) should do the trick. The flatlines put backspin on the balls as they go out increasing the range, and Tippmann is the only company that makes them and they only fit on there guns.
Unfortunately no. It would require heavy modification and machining to fit.
any carry case will fit. Or do you mean Carry handle? Opsgear, and many other scenario sites have them.
No. the thread pattern is NOT the same