What sie and type of rivets are used for the 1910 Maxim?
This great info.Assuming that you are asking about the rivets that hold the bottom plate to the sideplates, the OD of the rivets is going to be dependent on the restored size of the holes. To do a proper job of riveting, the holes will need to be trued between the bottom plate and sideplate by aligning the parts and drilling the holes so they are re-aligned and round. The rivet should be a moderate press fit through the holes before setting.
For a long time I have used 16D bright common nails to make rivets to assemble Maxkm plates. This spec is larger than the factory rivets and allows the holes to be cleaned up. They are +\- .164" OD, a #21 or #22 drill cleans up the holes and the fit is a good press. After cutting the head end of the nail off leaving 1 1/2" or so, the nail is chucked up and the OD of the head is brought down so the edges are square and small enough to fit correctly on the inside of the the bottom plate. The length is determined by how deep the chamfer is on the outside edge of the holes. I cut a light a 60 degree chamfer, and leave the rivet about 3/16" proud of the plate when pressed into the hole. On most 1910s the bottom plate rivets are set and then ground flush with the plate. Rivets on some very late manufacture guns were set as round heads or the set end of the rivet is left proud without grinding if flush with the plate.
You will have to design your own bucking system. Keep in mind that even if the rivet is a press fit, the impact of setting will tend to try and move it back out of the hole, so check frequently to see that the head remains solidly against the inside surface.
Hope this helps.