It is what it is...

The cheek riser is permanently attached to the buttstock however. 

I reinstalled the S&K scope mount and added Weaver Grand Slam steel rings with integrated square recoil lugs. The scope is a BSA Platinum 24x44 target scope with 1/8" clicks.

That was sitting at a bench with the forend resting in a tripod.

The round used was a duplicated M852 Match round.

42.0grns of IMR4895,  Federal Magnum Primers, LC LR brass, Sierra 168grn HPBT,  C.O.L. of 2.830"

Can’t believe I’m doing this, but here goes….

I dug out my Leupold Vari-X III 6.5-20x40 EFR Target Scope I bought in 1998 and mounted to my Fulton No. 4 Mk 1/3 for initial .303 load development work.  I removed it the next year and it sat in the box ever since.  It has a tiny diamond shape aiming point at the junction of the very fine horizontal and vertical cross hairs.  Parallax focus correction, 1/4 MOA click adjustments. 

Also found my B-Square Mount and Burris off-set rings.  The offset rings provides about 20 MOA of scope elevation offset above the bore axis at optical center.  I’ll need this to reach out to 1000 yds, which requires 37 MOA of elevation correction with my long range load and that will also give me more usable windage correction with the scope reticle closer to optical center rather near the extreme of the elevation range. 

Now installed on my UF 56 Mk 2 DCRA Conversion.  Of course, no modifications made to the rifle and it will be returned to SR(b) configuration after I do the accuracy tests at 800 and 1000 yds. 

Just doesn’t look nearly as classy as a “T”.  But, I’m just telling myself this is for the purpose of evaluating the rifle and load performance, not the shooters performance as I will be shooting it off the bench fully supported. 

My typical prone in sling slow fire groups with PH 5C aperture sights is 1.5 to 2 MOA for 10 shots.  I was expecting 1 MOA groups off the bench with 20X scope.  My average of four 10 shot groups off the bench with scope was was right at 2 MOA (at 200 yds).  

Typical group at 200 yds.  8 of 10 shots was good, about 1 MOA, but always the flier.  Note the X ring is 1.5 MOA. 

I thought perhaps the scope base was loose, but I detect no movement at all.  

So, scope is coming off, and PH 5C is going back on.  

So that’s my brief flirt with shooting a scoped No. 4 off the bench.  I’ll go back doing what I know how to do…

A lot of people give a short shrift to the AR platform and turn up their nose at "plastic rifles".  Fortunately, I'm not one of them.  One of the most accurate rifles I own is an Anderson Arms AM10 which is almost completely factory stock save a Geiselle Super Semi-Auto Enhanced  trigger and a muzzle brake.  I put an inexpensive yet excellent Nikon P-308 scope on it and it shoots 1 MOA all day everyday with a handload I worked up for it.  I use a Lead Sled to shoot from when working up handloads since I want to take as much of 'me' out of the equation as possible.  Just as you stated, anything over 1 MOA is because of me.