How important it is to lap rings before installing a scope?

[chgofirefighter]

Hello,


Under the direction of my gunsmith, he asked me to purchase a Warne X Skel mount for my AR platform, I purchased a scope 1-8X24. Once the mount was received, scope I took the items to him to have it mounted and set. I was charged quite a bit of money for his work; however, I didn't notice him lapping the rings. He did balance the scope, torque it to specs, bore sighted it, etc. But I'm curious if lapping the rings is something that needs to be done or should be done or maybe not?


I am thinking about purchasing my own tools to do my own work instead of forking over money to someone else. Especially for something that was quite simple to do, of course, after watching my gunsmith do the work...



Thanks~

 

[jds holler]

I like the idea of it, but I've never done it. With good quality rings, bases, and accurate mounting holes in the receiver, you can carefully line things up to where lapping usually wouldn't improve the situation.

The other night I mount a scope on a friends Ruger Hawkeye rifle. The Ruger integral rings didn't line up as nicely as I would have liked, and I would have liked to have lapped the rings.

I've not yet spent really big money on a scope, but when I do, I'll lap the rings. jd

 

[fguffey]

I took the items to him to have it mounted and set. I was charged quite a bit of money for his work; however, I didn't notice him lapping the rings.

Reloading forums are infatuated with neck tension, not me, again all of my gages are calibrated to deflection and or pounds. I know someone took a lot of time in an attempt to make it clear but the two manufacturers of bullet seating by the pound did not change their gages or start offering conversion charts for pounds to tensions.

If lapping was necessary it seems there would be a procedure for testing, it seems if the diameter of the scope is 1 inch as in 1.000" someone would have a way of measuring the inside and outside diameters of the scope and rings.

Crush fit and interference fit; I have bars that are 1.000" in diameter and then there are those that are + and or - and I have feeler gage shims, the most useful shims are the ones that are less then .001" thick.

F. Guffey

 

[WayneShaw]

Reloading forums are infatuated with neck tension, not me, again all of my gages are calibrated to deflection and or pounds. I know someone took a lot of time in an attempt to make it clear but the two manufacturers of bullet seating by the pound did not change their gages or start offering conversion charts for pounds to tensions.

If lapping was necessary it seems there would be a procedure for testing, it seems if the diameter of the scope is 1 inch as in 1.000" someone would have a way of measuring the inside and outside diameters of the scope and rings.

Crush fit and interference fit; I have bars that are 1.000" in diameter and then there are those that are + and or - and I have feeler gage shims, the most useful shims are the ones that are less then .001" thick.

F. Guffey

WTF? Why don't you answer the guy's question. Who needs to test? You put a 1" bar in the rings (or 30mm) with some lapping compound, and stroke it back and forth a few times. Clean off the compound and LOOK at it. There is your test.

 

[fguffey]

Wayne Shaw, why are you so angry, before lapping I had rather make sure the rings are aligned, I understand it is fashionable to twist the front ring on some designs to install with the scope. If I install the rings and the bar slides back and forth 'smoothly' lapping may not be necessary. The OP did say installing the scope and rings was expensive and he did say he did not get the benefit of lapping.

WTF? Why don't you answer the guy's question. Who needs to test? You put a 1" bar in the rings (or 30mm) with some lapping compound, and stroke it back and forth a few times. Clean off the compound and LOOK at it. There is your test.

I can only imagine the OP going back to the smith complaining about what he should have gotten for his money. And then? He tells the smith he learned all of that from the Internet.

F. Guffey

 

[LHSmith]

Hello,


Under the direction of my gunsmith, he asked me to purchase a Warne X Skel mount for my AR platform, I purchased a scope 1-8X24. Once the mount was received, scope I took the items to him to have it mounted and set. I was charged quite a bit of money for his work; however, I didn't notice him lapping the rings. He did balance the scope, torque it to specs, bore sighted it, etc. But I'm curious if lapping the rings is something that needs to be done or should be done or maybe not?


I am thinking about purchasing my own tools to do my own work instead of forking over money to someone else. Especially for something that was quite simple to do, of course, after watching my gunsmith do the work...



Thanks~

A new term for me....could you explain what was done to "balance" the scope?

 

[Fast14riot]

The xskel and most AR rings are 1 piece bases, they're usually better than separate rings at being aligned to each other, but not always perfect. IMO it's probably best to check 1 piece mounts as they can't be turned or moved relative to each other.

I don't lapp my AR mounts, personally.

 

[RWO]

Non swiveling rings such as Weaver style depend on the manuf. precision to align perfectly. On a one piece base, the alignment is usually pretty good. If two- piece bases( any style) are used, all bets are off. One way to eliminate all the checking, lapping and otherwise fooling around is to use Burris Signature rings. They are made to fit the common base styles. The various nylon inserts provide for perfect alignment, non-slip grip on the tube and no ring marks. The eccentric inserts can also allow a scope with centered adjustments to be bore sighted with even misaligned bases if needed.

RWO

 

[BoydAllen]

Look, there is doing it right and there is not....unless you are using Burris Signature type rings with the plastic inserts, rings need to be lapped or bedded. Why would you want to do second rate work? For steel rings you can save a lot of work by doing some lapping and then bedding the rings. I have lapped a lot of rings, and when someone says that if you have good rings yada yada yada. I know that he has never lapped a good set of rings on a base that he thought would eliminate the need to lap. I absolutely never use twist in rings. I am pretty sure that you will never see them on any rifle built to competition spec's. I know that I have never seen them on a benchrest rifle. BUT it is your hobby. Do what pleases you.

 

[X Ring Accuracy]

Flame suits for everyone : )

 

[WayneShaw]

The subject of lapping rings are as toxic as what brand of motor oil to use. It's amazing how people look at it. While I agree about the rings being in alignment, it goes beyond that. People think because they buy very expensive rings and bases, they will fit perfect. And, people aren't bothered in the least their scope has gawdy rings marks on them.

And bedding scope rings? As Boyd says, sometimes bedding is needed to correct things a simple lapping won't fix. Don't half-a$$ it. Scopes are expensive. And we like them to work properly.

 

[chgofirefighter]

The subject of lapping rings are as toxic as what brand of motor oil to use. It's amazing how people look at it. While I agree about the rings being in alignment, it goes beyond that. People think because they buy very expensive rings and bases, they will fit perfect. And, people aren't bothered in the least their scope has gawdy rings marks on them.

And bedding scope rings? As Boyd says, sometimes bedding is needed to correct things a simple lapping won't fix. Don't half-a$$ it. Scopes are expensive. And we like them to work properly.

True ~

 

[jepp2]

My practice is to lap scope rings before mounting my scope. You find spots that are going to create pressure. Interestingly enough, on the Leupold rings with the L on top, that is where I find the most material removal. Any misalignment shows up very quickly.

However, I tend to use the Leupold Mark 2 IMS mounts on AR's. And I used them without lapping. The most recent one I mounted, I did lap. And I found it was the most uniform in material removal on any I have ever lapped. The picture I will include below shows removal on all 4 surfaces. IF, if the Warne X Skel is as well aligned as the Leupold (and it probably is), I think you have very little to gain. But that is your call.

 

[gotcha]

Nice lapping job Jepp !! ............... I've always wondered why the screw holes on the Leupold ring caps are drilled closer to the scope body than the holes on the bases (I've lapped more than a few of them) .......... Do you happen to know the reasoning on this phenomenon ???? IE: would the offset holes possibly defeat a 360 degree contact to the scope upon tightening?? ............ Anyone ?

 

[savagedasher]

Lapping rings I feel if isn’t done . Can cause scope movement most scopes have aluminum tubes .
If the rings are missed aligned when tighten the distortion of the tube happens . Good job Larry

 

[mbz hunter]

I like the idea of it, but I've never done it. With good quality rings, bases, and accurate mounting holes in the receiver, you can carefully line things up to where lapping usually wouldn't improve the situation.

The other night I mount a scope on a friends Ruger Hawkeye rifle. The Ruger integral rings didn't line up as nicely as I would have liked, and I would have liked to have lapped the rings.

I've not yet spent really big money on a scope, but when I do, I'll lap the rings. jd

I typically lap the rings (gently!) with 400 grit and a 1" stainless bar, just to see if there are any obvious imperfections in the fit. If it doesn't look too bad I'll go ahead and assemble. There is enough flex built into good scopes that perfection isn't needed.
OTOH, the worst misalignment I have seen was on a Ruger 77 with the integral bases. I never bothered to measure it, but it took the whole length if the rear ring surface to get even with 50% of the front. Checking that stuff can pay off...

 

['Freak]

Wouldn’t scope rings misalignment result in stresses not only on the scope tube but also on the action?


I hate on Ruger’s rings and even more so, their action attachment scheme. I mount both ring halves on a 1” SS shaft (don’t have a 30mm, yet) leaving ‘em just loose enough they’ll slide. Then once located where they need to go on the action, I first tighten the ring halves to the shaft so they’ll maintain position whilst tightening snot out of ‘em to the action. So far over the years I’ve not had any shoot loose, but then those were huntin’ guns that didn’t see all that much shootin’ unless playing with different loads, or just playing...