Enter your scope's objective size and tube diameter to get the minimum ring height that clears the barrel, then compare ring heights and AR mounts, including Badger Condition One and UNITY FAST LPVO. Preview each height in 3D to see the gap under the scope. Every height runs from the rail top to the scope center. For a full walkthrough of bases, torque, and leveling, see the optic mounting guide.
The second number in the scope name: a 5-25x56 has a 56mm objective lens.
Calipers across the widest point of the objective bell. Left blank, the housing is estimated at +8mm over the lens.
If the bell hangs past the rail over a lower barrel, lay a straightedge on the rail and measure down to the barrel. Leave 0 for the safe answer.
Based on a 58mm bell (estimated), 0.13" clearance, with the bell over the rail. Pick the lowest ring at or above this number: every extra tenth of an inch raises your head off the comb.
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Vortex Precision Matched 30mm Extra-High (PMR-30-145) · 30 mm tube · 58 mm bell (estimated)
Drag the 3D view to rotate. Side and front views stay fixed for comparison. Model shapes are illustrative and adapt to your height and tube size. Check eye relief, bolt-handle clearance, and fit on your rifle.
Take half the objective bell's outside diameter (the bell housing runs about 8mm wider than the stated lens size), add at least 0.125 inch of clearance, then subtract any drop from the rail surface down to the barrel under the bell. For a 50mm scope sitting over a flat Picatinny rail that works out to about 1.27 inches to the ring center (58mm bell = 1.14 inch radius plus 0.13 inch clearance), which lands in most brands' High rings, like the 1.26 inch Vortex Precision Matched High or Seekins X-High.
Most brands (Vortex, Seekins, Leupold, Burris) quote the distance from the top of the rail or base to the center of the scope tube. Warne is the common exception: it quotes base-to-saddle, the distance from the rail to the bottom of the ring cradle. To compare a Warne number against everyone else, add the tube radius: 0.591 inch for a 30mm tube, so a Warne 0.375 inch Medium is really a 0.97 inch center height.
A minimum of 1/8 inch (0.125) between the objective bell and the barrel is the standard guidance, and it is what Nightforce recommends. Flip-up lens caps add roughly 3mm to the effective bell diameter, so budget extra height if you run caps. More clearance than the minimum costs nothing but cheek weld height, so do not chase a paper-thin gap.
Pick the lowest rings that clear the objective bell with your clearance margin, because every extra tenth of an inch of ring height lifts your head off the stock comb and degrades cheek weld consistency. Vortex's own mounting guidance says to only go high for clearance reasons. The exception is deliberate high mounting for a heads-up position on defensive carbines, which is a different use case from a precision or hunting bolt gun.
Over a full-length flat rail, a 56mm scope needs about 1.39 inches of center height (roughly 64mm bell = 1.26 inch radius plus 0.125 clearance), which means extra-high rings like the 1.45 inch Vortex Precision Matched Extra-High or Seekins 1.45 AR-High. On a bolt action where the bell overhangs a barrel that sits below the rail, the drop often buys back 0.3 to 0.5 inches, letting 1.26 inch High rings clear. Measure the actual drop with a straightedge before buying.
Start by comparing 1.50-1.54 inch mounts with your preferred head position. Badger Condition One also offers 1.70 and 1.93 inch heights in 30mm and 34mm, while the UNITY FAST LPVO uses a 2.05 inch centerline in those two tube sizes. These heights run from the top of the rail to the scope center. Bell clearance sets the minimum; head position and eye relief help you choose among the mounts that clear.
No. Ring bore diameter must exactly match the scope's main tube diameter: 1 inch, 30mm, 34mm, and 35mm are all separate ring sizes. Clamping a 30mm ring on a 34mm tube is impossible, and shimming a 34mm ring down to a 30mm tube will crush or slip. Check the tube spec on the scope's data sheet, not the objective size.