Mounting Instructions



You have purchased a very precise scope mount. The mount has been CNC machined using materials that were processed to prevent warping during the machining process. This does not mean that it will fit perfectly to your receiver. Most receivers that are cast have been ground and polished, depending on how aggressively that was done can make the difference in your rail setting flat and having the proper MOA . It may be necessary to use an epoxy bedding,  to prevent stressing or bowing of the mount and to maintain the straightness of the mount. In many cases you may not need anything most round style receivers are generally turned true and most likely will not require bedding, just mount to the receiver with the four screws provided and tighten to specs and enjoy.

In some cases the provided screws may need to be ground according to the amount of threads in your receiver. Try to get the maximum amount of threads engaged in your receiver. We have counterbored the holes in the mount to control the depth of thread but some rifles that have had a larger diameter barrel installed can cause the screw over the barrel threads to bottom out. This can be checked by installing that screw first and just snugging it. Should the mount feel loose, the screw has bottomed out and may need to be ground.


A set consists of two rings completely CNC machined from solid stock. The rings are machined in pairs and are serial numbered as machined and are absolutely matched to within our standard tolerances of .001 of center line of our base.

In most cases our standard rings will clear a 50 to 56 mm objective bell, according to Barrel diameter and MOA. All factors need to be known to get the right height of rings. The barrel diameter, the length of the scope, how tall the base is and its MOA along with the step from the receiver to the barrel. Another thing to consider is your cheek weld. A lot of rifles have been designed to use open sights once a scope is installed the aim point has become at least 1.5" above the plane of the open sights this is a function of the stock more than anything, keep these things in mind when looking for optical options.

Most scope bells will have an outside diameter that is 10 to 12 mm larger than the objective lense itself so a 40mm bell would be approximately 52mm this will vary but it is a good start. The chart below demonstrates using our standard ring which is .835" from top of the base to centerline of scope tube and using our rail that is .480 from the top of the reciever.

Farrell Standard rings, Farrell 20 MOA base, 30mm scope tube and 1.0" barrel diameter are being used for this example. You could use low rings in this scenero but you must take into account for the style of barrel and if you want to use scope covers, which you need around .130 clearance for scope covers depending on the manufacturer. These are approximate you must measure your equipment. We will be glad to assist you with that,  Call us if you need help at 660-438-9456.

  Objective Lens Diameter..............Bell Diameter.....................    Gap       

                40mm  ...............................52mm+-.............................   .486"

                50mm ............................... 62mm+-..............................  .266"

                56mm ............................... 68mm+-..............................  .148"




Things needed:
2 part epoxy (JB Weld is only one of many on the market)
Release agent: 3 in 1 or a good silicone release agent (it has been reported case lube works well also) to prevent mount and screws from sticking to receiver. (3 in 1 sells a silicone lube at about $3.00 that works well.)
Q-tips to apply release agent and clean excess epoxy.

  1. Put release agent on screws and receiver
  2. Apply epoxy to bottom of mount between screws and on each side of screws
  3. Put all 4 screws in mount holes.
  4. Set mount carefully over mounting holes in receiver
  5. Thread down into the receiver
  6. Do not tighten the 2 outer screws. Tighten only the 2 screws next to the ejection port. The outside 2 screws at this time is to prevent epoxy from entering receiver holes.
  7. Clean excess epoxy from sides of mount using a thinner of some sort (paint thinner, alcohol, or whatever will clean the excess epoxy). Q-tips work well.
  8. After epoxy has set up according to its instructions, you can now loosen and then retighten all screws according to torque specs shown below.
  9. You now have a very flat mount with little or no distortion in receiver or your mount.
  10. We can only speak for our rings. THEY SHOULD NEED NO LAPPING as our rings are perfectly matched and when using the proper torque will repeat to each other when tightened properly.


Suggested tightening torque for all screws: 20-25 in/lbs.


Suggested tightening torque for ring caps: 20-30 in/lbs. depending on the weight of the scope and caliber of the gun. Average is 25 inch lbs. Follow the scope manufactures torque specs if provided.  When installing the cap screws they should have no resistance.
Suggest torque for ring cross bolt to the mount: 50-60 in/lbs.

With Adjustable Recoil Lug

  1. Make sure the recoil screw is not engaging the receiver before installing.
  2. Install the mount in same manner as our standard mounts. Tighten all 4 screws completely. (Standard mount instructions supplied)
  3. Adjust the recoil screw until it engages inside face of the ejection port.
  4. Apply about 35 to 45 inch pounds of force to recoil screw and then back it off. This will cause the mount to move approximately .002 to .003 rearward which acts as a preload for final adjustment.
  5. Final adjustment; apply only 5 to 15 inch lbs. of force to recoil screw. At this point there will be no more movement in any direction.
  6. It is advised to recheck final adjustment after each of the first few shooting sessions, as the lug will continue to seat better after each session.
  7. The 45 degree angle on the adjustable lug will cause a slight indentation in the receiver. This will have no effect on the accuracy of the rifle, and as mentioned will improve the seating surface with each shooting session. This mount was intended to be used on larger calibers with heavy recoil.
  8. For those who do not have an inch pound torque wrench, make contact with receiver using the 1/8 allen key. Now tighten 1/8 of a turn to pre load mount.
    Back off the lug screw and re-adjust using only enough pressure to contact receiver.


Have fun and enjoy some great shooting
If you need further assistance, call 660-438-9456.

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