Take pictures of the parts, post them in the thread. Include a tape measure in the pic with the parts.
Need details on what you have, and you're not giving enough details. There's no way to help you without the information. The only way we can get the information, is for you to tell us what you have. Parts dimensions,weights, who made them (what brand?), where you bought them (good vendor or shady vendor?). I think you get the point.
Start with names. What's the names of the gun parts you have - what brands are the parts? Then, add descriptions of the parts - that's where the measured dimensions, weights, etc., come into play.
Without accurate info, we're flying blind here, in any attempts to help you.