[Kos-Mos]

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Have you ever upgraded/fixed a BA rifle?

Do you understand how the VSR-10 and it's clones is working?

You can fix the slam fire by simply file the first sear (the one on the piston, Amos, that is sear #2) at a slight (barely, not even enough to see it) angle. The stock part of casted and most of the time the edge is rounded and will cause the piston to slip, especially since there is a lot of grease everywhere in clones.

If you bought the piston I think, it is normal that you have a hard time to fit it inside the cylinder. The ones I am talking about are made with a thin lip all around the piston head. The lip is so soft that it will grab on the treads and jam between the piston and cylinder.

There also is 3 different versions of VSR-10 cylinder sets.
Regular
Bore-up
Short stroke

Make sure you bought the right parts for the right version. The stock one should be a regular. By the issues you are describing, you might have bought a bore-up kit.

Double feed can be caused by a lot of other things than the little "U" shaped stop. You barrel might not be seated properly, you hop-up unit might be loose, your hop-up rubber can be set wrong or deformed.

The bipod mount on the TSD M700 is molded in the stock plastic. It is bound to break. You can buy a separate nub and replace it VERY easilly by drilling a hole for the screw and place it at the same place the stock one it. You can also simply install a 20mm rail at the same place, using the front barrel bolt and make a hole for the second one. G36C rails work good for that.

By the way, upgrading a BA rifle (or buying a cheap clone to do so) means that you will only have the barrel, receiver and stock left from the original rifle.

It is not like an AEG where you change a spring and 6 nylon bushings and you are done.