So I finally decided to try a tac scope. Found a good trade for a vortex pst 1-4. It came with two arms qd mid rings. I actually like the height and would like to hang in there with them for a while. Not really in a hurry to buy a $150 mount atm. However, it straddles the upper and handgaurd as it sits and I need it more forward still. Looks like this.



I know the ideal thing is to just get an appropriate mount. The question is. What if I moved the forward ring behind the turrets? Would any undesirable effects stem from not having support on the front of the tube? Areas marked in yellow.



Not wanting to fo right now because I'm unsure if I want to keep it or not. Sometimes I want to say screw it and go irons.

If this would be harmful to the scope than its a no go, any thoughts?

I guess the real  question is will mounting the scope straddling the upper and guard effect accuracy?

I wouldn't bridge like that.
Just move the mount and scope back some.
You may have to move your head a little, adjust.
But I'm guessing with a 1X4 on it, its not like you plan to be laying on the scope all day.

Or just spend the $ and get a 1pc extended scope mount.

It could, and I'd venture a guess it's a lot more likely since you're not using a 1 piece mount.  

FWIW, you don't need to spend $150 and it doesn't have to be QD for you to get a quality 1 piece cantilever mount.  I've heard good things about the SWFA S.S.A.L.T. and the Burris PEPR mounts.

I'm familiar with the ssalt, was also looking at aero precision, and vortex for that matter. Do you know of a 30 mm mount that's medium instead of cowitness height?

I'm not really sure about the height thing.  Is "medium" taller or shorter than "cowitness" height?

Medium rings are lower than co-witness, in fact extra tall is lower than co-witness. Larue's cantilevered scope mounts center the crosshairs at 1.5" which is close to dead on co-witness. Leupold's cantilevered bases center the scope at 1.4" which I think is perfect for me. 1.375" works great for me as well.

Many people will advise against jumping the front scope ring on to the free float tube but I have done it without any problems on some builds. If your float tube has any movement in it it's not installed properly. Your scope centerline and position has to work for you. It needs to be perfect regardless of magnification setting or shooting position. If that means moving the front ring forward so the entire scope can move forward than so be it. The rear ring can go forward as well but forward movement will be limited by the elevation/windage turret.

Cantilevered scope mounts are the best, but your rings will work if they're high enough for you.

This is good advice, but I still avoid bridging to the tube, no matter the quality, as it will flex somewhat, especially with a bipod.

Safest course would be a decent cantilever one piece.  Another choice not yet mentioned is the Leupold Mark 2 IMS at about $100.

Thank you for the leupold suggestion, but that's still too far back. I need it in front of the charging handle more than it already is. For what it a worth ,I prefer the mounts that cantilever straight out opposed to the ones that angle up. Purely aesthetic. But I prefer it. Still not even sure if the tac scope is for me. I got used to binden shooting with my eotech. But I'm left eye dominant, right hand shooter. Trying to look through this this with both eyes open is very tough. Practice more I guess.

I love my Aero Precision Ultralight SPR mount.  I have used LaRue and ADM mounts on several ARs. For non-quick detach, I have used PEPR and some other I cannot recall, along with the Aero below.  If you need QD, LaRue, Bobro, and ADM are all great.  If you are not in the need of QD, the Aero ultralight blew the PEPR out of the water.  It is so light, I could hardly believe it.

Vertexops.com has some in stock and primary arms seems to get them from time to time.

Turns out that leupold ims can be bought locally for $99. Unless something on the fb groups pops for cheaper I'll give it a shot.