You cant only use Fragmotion, you need to:
-export the skeleton you want to milkshape,
-export the weapon you want to rig to that skeleton to milkshape, -open the file of the skeleton you want to rig the weapon to, -delete ONLY the weapon and save,
-open the weapon you will be rigging to that skeleton,
-delete the HANDS ONLY and save
-open the skeleton's model
-merge with the handless weapon model and assign every group of that weapon, to the bone that uses that particular group or part,
-export back to fragmotion
-make sure that the model looks okay and export the weapon to the HUD.x file
if you do all of this correctly, then you should have a weapon capable of iron sights, although, sometimes there are animation issues, and if you get those, then you have to manually retype the frames in the gunspec, its a long, hard process, put the reward is worth it
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