Here is my 22 upper with measurements. I'm wanting to put a rail on it. I don't want a bigger rail. I think the suppressor under the rail looks awesome, but its just not what I want. I want the hand guard to come up to the threads, but I don't think anyway makes a 3 inch handguard.

Here are some pics for everyone else who wants to see how much space is available with a 4.5 inch 22 barrel.

to the tip of the barrel


and this is the length of the YHM mini rails, which are 4.15. This show that the rail would go over the ports.

You are going to have to go custom or use a pistol/mini rail. Maybe cut a carbon fiber hand guard.

MAHA

I have a 4 inch pistol rail that could be cut down with out a lot of effort...it would bisect some of the vent slots but we could turn a trim ring to press in and make it not look like it was cut off....I'm off I-475 in Macon if you can/want to come by and look at it.......or a 3 inch custom is doable.....
Rudy

You can use a car rail & use one of the 5.5" FH for clearance.