I'm currently buying parts for a 12.5" 308, and I'm looking at the SLR Solo Mid series rail (ID of 1.5").  I plan to use a Saker 762 with the rifle, and I'm trying to figure out if the Saker has an exact OD of 1.5", or if it will fit under the rail.  I'm not looking to have the suppressor completely covered, just the first 1/3 of an inch (basically, the suppressor would sit right inside the rail).  I read somewhere that silencerco said if you have an ID of exactly 1.5" the Saker would fit, but I though I would ask everyone here if they have any firsthand experience with it since I only saw that one mention of it.

Just call each and get exact dimensions.

I wouldn't do it. My YHM is 1.5'' diameter and inside the 1.56'' Samson/Rainier handguards it would contact the rail when firing. It was only about an inch inside the handguard.

You don't want them within a few thousandths of each other, even if they fit together. Remember, the silencer will expand when it's hot, and if it touches your rail at all it can open up your groups. I wouldn't do it.