How do I know when to lap rings?

Davy Crockett

Davy Crockett

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So, I bought a one piece Armalite mount and I read some comments about the rings being out of round on a few of these.

Maybe I'm being over concerned, but how do I know if the rings are ok? I'm going to get a torque wrench to make sure that I don't over tighten things but I don't want to damage a scope if the rings are out of whack.
 
I have only found one pair of rings that didn't really need to be lapped they where made by Hart any other always need to be done to make good contact.
manitou
 
Most aluminum rings (as yours are) do not require lapping unless your just trying to make sure everything lines up perfectly. Considering the smaller scope and application I don't think I would bother. Phil.
 
Ok, thanks guys. I was just concerned about damaging the scope tube.

Now, maybe I should start a new thread on this but is there a proper sequence to torquing down the bolts on the rings?
 
Check this out, it's a video from U.S. Optics on how to mount your scope. I wish I knew the torque on the ring screws when I was mounting my scope - I went too light and bye-bye paint finish on a 2000$ scope :mad: because it slid after a few shots.
 
You can place the scope in the rings, pushing lightly with your hand and see what you can see. It is very tough to see any misalignments by eye but you sure know when you take the scope off again and there are rings marks.

With quality rings, the problem is the base or action. Many bases are not true which then causes the base and rings to be out of whack.

My solution is to use Burris Sig rings w/inserts. never any issue with alignment and they hold like crazy when properly installed. I use nothing else on my rifles.

I assume you are putting a scope on an AR? These can be tricky to keep a scope still as there is a constant pos and neg shake to the scope and rings. Rings can slip under these conditions.

As for torque, I like them tight..

Jerry
 
Thanks Jerry

Tight is subjective, especially for newbies like me. I've seen suggestions of anywhere from 15-30 in/lbs on the ring bolts. I thought I'd start with 20 and see.

Since this is a one piece mount I'd assume the alignment issues should be less than with separate rings/bases? I guess rather than dwelling on it I'm just gonna giver and see how it goes.
 
If you do lap, how are you going to be sure that whatever you use to lap with is more precise then what was used at the factory? All of the tools I have seen are T shaped. From this, I can deduce that they will rock slightly in the rings.

I have never lapped a set of rings. I always buy badger/nightforce/ADM though. Maybe that helps. If I thought that there was a decent probability that the benefits would outweigh the risks, I would do it in a heartbeat.
 
carbonrod said:
If you do lap, how are you going to be sure that whatever you use to lap with is more precise then what was used at the factory? All of the tools I have seen are T shaped. From this, I can deduce that they will rock slightly in the rings.

I have never lapped a set of rings. I always buy badger/nightforce/ADM though. Maybe that helps. If I thought that there was a decent probability that the benefits would outweigh the risks, I would do it in a heartbeat.
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Almost all of our scope installations include lapping especially when using steel rings. You would be surprised how many rings are not round inside and require care lapping to make sure your getting maximum contact between the ring and scope body. Lapping ensures that by using the steel lapping bar you are making as near perfect a channel to receive the aluminum body of your scope. We get some rings (notably Ruger rings) that are either so out of round or have high and low spots that sometimes less than 10% of the ring contacts the scope body. With any kind of recoil or hard use it will allow the scope to move in the rings causing your zero to move and/or damage the scope. We now use a hand reamer that allows us to shave off more metal in a shorter period of time when we find rings that are far out of alignment. Some manufactures like Leupold are usually more precise than other and require only lapping. Higher end rings like Mark 4's and Nightforce are very precise. We use the lapping bar also to confirm alignment of turn in rings. We seldom lap aluminum rings other than to check alignment. When lapping/reaming we always do the tops of the rings in place which takes a lot longer but ensures a prefect fit. Phil.
 
Davy Crockett said:
Thanks Jerry

Tight is subjective, especially for newbies like me. I've seen suggestions of anywhere from 15-30 in/lbs on the ring bolts. I thought I'd start with 20 and see.

Since this is a one piece mount I'd assume the alignment issues should be less than with separate rings/bases? I guess rather than dwelling on it I'm just gonna giver and see how it goes.
Click to expand...

You are right about how tight is tight. I use a small rachet with a torx bit (seems to be popular hardware these days), allen key would be the same thing. I tighten until the bolt is snug. Wait a few seconds, tighten a bit more. Wait and repeat but not really increasing pressure (again, there is the feel thing). IF you are bending the allen key, too tight.

You will not be able to move that bolt anymore unless you apply alot of pressure and start bending that allen wrench.

A 1pc base will help BUT what happens when the action you are bolting to is not true - either screw holes are not aligned or the action is cockeyed?

When you tighten the base on, something has got to give and I bet it will be the base before any action. Also, with turn in rings, how precise is the machining in the slots? How precisely does the ring fit in that slot?

It is the stacking of tolerance that eventually ends up causing problems. No one area is really that bad but if all the errors are the 'wrong' way, you are going to have fun getting that scope true.

Phil, I think your approach is a superb one and the one most will consider using. The problem is whether true or cockeyed, the hole in the ring is 1" or 30mm or whatever from the manf.

How do you remove material and still retain the same size and shape?

IF the ring manf started making UNDERSIZED rings, now you have my attention. That gives me an idea....????

The best rings in the world are still limited by the weakest link during the install and that is the action. NF, Mk4, Kelby on a wonky action is still going to lead to problems...

Jerry
 
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