You have several options. One is to call Tippmann and get replacement screws from them. Another is to order from any of the online retailers that carry Tippmann parts. A third is to go to your local field/pro-shop and get new screws from them. The fourth is to go down to the local hardware store and get some 10-32 screws, preferably ones that take an allen key to tighten.

If the screws are rounded off to the point you can't get them to loosen up there are a few different methods. One is to use a similar size metric allen key or use a slightly larger standard allen key. The second is to use a screw/bolt extractor such as an easy out. The third option is to use a Dremel or hacksaw to carefully cut slits in the bolts so you can use a flat head screw driver.

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