Lap those rings! Keep that scope looking like new.

[TAJ45]

I'll have to say I'm more than a wee bit surprised after having read all the replies.

I've read of the horror stories of how bores/chambers were very much out of alignment/true/square from Big Green et al. If those dimensions fall under "manufacturing tolerances" why wouldn't the action dimensions, where the scope mounts fit, fall under the same umbrella? I've also read were the D&Tapped holes for the base(s) were way off.

If where the bases are located aren't near perfect as well as the dimensions of each base (a one piece base will help remove the last variable) then all of the "most perfectly mfrd rings" won't amount to squat. Because of this misalignment of the foundations - bases, rcvr dimensions in front to back relationship (height as well as radial variation) and the true positioning of the d&t holes the best rings in the world are at a severe disadvantage of doing a non marring job.

The idea of "windage" bases just cross threads my head. :'(

OBTW One little trick that hasn't been mentioned on the side yet even though not a cure for misalignment, is lining the rings with plain old Scotch Invisible tape to increase the grip of the rings. I can usually get one side pretty close and just razor off the overage.

 

[Jonl]

I just had a local machine shop cut me a 12" piece of 30mm cold rolled and 1" cold rolled for ten bucks. I am sure this is what you get on e-bay for 50 bucks.

 

[TAJ45]

I just had a local machine shop cut me a 12" piece of 30mm cold rolled and 1" cold rolled for ten bucks. I am sure this is what you get on e-bay for 50 bucks.

Personally, I'd have gone with drill rod for concentricity. Sticks of this are in MSC and probably Graingers as well as many other supply houses. The tolerances allowed? A world of difference.

 

[nhm16]

Personally, I'm a fan of Signature Zee rings. But one thing that can be done easily with metal rings, short of lapping, is a simple deburring of the outside edge. You will often see that the ring marks are found right on one edge or another. You don't need to chamfer the outside edge of the ring -- merely smooth away any high spots. This can often be done with a quick pass of a scotchpad. When I saw race engine builders doing this deburring with brand new CNC-machined parts, I realized that there can be a slight rise on the outside edge of the machined part.

Agreed.

I too am a fan of Signature Zees, and use them when possible. For my tactical rifles, I use Seekins rings, which have a very smooth finish, which have never left ring marks if torqued to spec and if I bed the scope base to the action.

I recently got a Panda action and a set of Kelbly rings, and was surprised how rough and gritty the inside edges were. Just mocking up the scope by resting it gently on the rings, I could tell I would get ring marks if I actually mounted the scope. A quick pass with some 0000 steel wool on all the edges that could touch the scope took care of that.

 

[Jonl]

Actually it was drill rod. I asked him for cold rolled and did not
Know what drill rod was.

 

[TAJ45]

You won't be sorry........glad it worked out for you.

 

[GSPV]

The point of the whole exercise is to have a mount, ring, scope system that is free from stress.

Think about the whole deal. Think about the assumptions that are being made and eliminate them.

One assumption that almost everyone makes is that the scope tubes are perfectly aligned. They are not. The only question is how much out of alignment they are.

I started lapping and epoxy bedding...when not using the Zee rings...after making a jig with a 1/1000" dial indicator and measuring total indicated runout on one of my favorite scopes. The result sent me into a fit and I checked all my scopes...and gave me my lap-and-bed fixation.

My grandfather told me "The worst measurement is better than the best assumption". Something to live by there.

 

[TAJ45]

Greg, is your experience with one piece tubes??? If so, how much r/o were you getting, ballpark, say 2" fore of the turrets and 3" aft? This being on quality = say Bushie/B&l 4200-4000 or Burris Sig scopes.

 

[GSPV]

I have Leupold LCS, NF BR and March. I have a NF Competition, but have not measured it.

The rollers were at the beginning of the ocular lens bell and the dial indicator at the beginning of the objective lens bell. Every scope that I've ever measured had substantial runout. One NF BR, since sold, reminded me of a banana,

I do not think that the small amount of runout affects their optics, per say. I think that if you do not account for it, it induces stress.

We go to all the trouble of creating a stress free bedding job for the action which, compared to a scope, is incredibly rigid, and do not consider it for that flimsy little scope? Then we whap it with 60,000 psi right below it?

Maybe I'm paranoid, but I'm very happy being kind to my expensive little optical investments.