How to bed a rifle scope base

January 17, 2014 Bill Marr Gunsmithing, Optics 0

I was able to measure the space at .010" with a feeler gauge. I'll be bedding this base.

An important part of building an accurate rifle is eliminating stress in the various components.  On the Remington 700, once piece scope bases can often require bedding in order to get the most out of your rifle and optic.

To complete this project, I ordered the following supplies from Brownells:

  1. Marine-tex epoxy (904-301-102)
  2. Badger Ordnance Maximized scope rail for Remington 700 (093-306-070)
  3. Abrasive cloth (657-110-120)
To see if the scope rail needs to be bedded, I attached the rail with the two front screws. Notice the space under the rear of the base.
To see if the scope rail needs to be bedded, I attached the rail with the two front screws. Notice the space under the rear of the base.  Just screwing down this base would bend the rail and potentially degrade accuracy.
I was able to measure the space at .010" with a feeler gauge. I'll be bedding this base.
I was able to measure the space at .010″ with a feeler gauge. I’ll be bedding this base.
I begun by degreasing the bottom of the base. I use 120 grit abrasive cloth to remove the finish on the bottom of the base, along the mating surface. The clean metal will allow the epoxy to adhere to the base.
I began by degreasing the bottom of the base. I use 120 grit abrasive cloth to remove the finish on the bottom of the base, along the mating surface. The clean metal will allow the epoxy to adhere to the base.
I use paste wax as a release agent. I don't want the epoxy to stick to the action or the sides of the bases.
Here I am using paste wax as a release agent. I don’t want the epoxy to stick to the action or the sides of the base.
I mix some Marine-tex on a piece of scrap cardboard and apply a light coat on the mating surface of the base.
I mix some Marine-Tex on a piece of scrap cardboard and apply a light coat on the mating surface of the base.
Using a cotton swab I remove the excess epoxy.
Using a cotton swab I remove the excess epoxy.
When the epoxy cures, I remove the front screws and inspect my work. I use a drill bit to clean epoxy from the scope base holes.
When the epoxy cures, I remove the front screws and inspect my work. I use a drill bit to clean epoxy from the scope base holes.
With the scope base bedded, I reassemble the rifle and head to the range to check my work!
With the scope base bedded, I reassemble the rifle and head to the range to check my work!
3 rounds in 4.5" at 500 yards. This was shot using a 3 mil hold over on the reticle. This works out to around .860 MOA. I think the group would have been better if I dialed in correction.
3 rounds in 4.5″ at 500 yards. This was shot using a 3 mil hold over on the reticle. This works out to around .860 MOA. I think the group would have been better if I dialed in a correction.

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