Is Scope Lapping necessary?

[cdb1]

I guess you are on Ruger’s doo doo list since you are the only person I’m aware of that’s ever had this issue.

 

[oldfortyfiveauto]

The scale check is pretty simple and easily done.

Ruger uses all those investment castings which are pretty good. Regrettably they don't always leave enough material to clean up machining. The problem with their rings is the mating surfaces are not fully machined to contain tolerances which is why you see this problem. If I had the time I would have set the rifle up on my surface plate and measured it up for real numbers. Another area on Rugers you need to watch is on their O/U shotguns. The trunnions the barrels pivot on usually come up short on material and only show machining on less than the full area. Those will shoot loose pretty quick.

 

[Walkalong]

Sorry but they are supposed to be the same.

Not on the Rugers I have/have had, they use two different height rings.

 

[oldfortyfiveauto]

Not on the Rugers I have/have had, they use two different height rings.

On the full size yes, but the 77/17/357/44/22’s use the same.

 

[cdb1]

Have you ever contacted Ruger and discussed these anomalies with them oldfortyfiveauto?

 

[oldfortyfiveauto]

Yes and they act like its not a problem.

 

[cdb1]

When I think about how much elevation can be gained using a shim the thickness of a coke can, it would seem people wouldn’t be able to bore sight much less sight in their rifle with those rings being so out of alignment.

 

[Cowhide Cliff]

No Leupold rings I have ever installed have had better than 50-60% contact, most are less than 50% - this is their precision. The cheaper Leupold rebrand/contract rings are just as bad as any of the other junk on the market, 20-30% contact.

That is because of the design and how they are mounted not quality. Once fitted on that particular receiver and lapped they are a strong setup.

 

[cdb1]

I like Leupold Std. rings okay although they are never my first choice. The Leupold Rifleman rings are horrible IMO. Just looking at them makes me wonder how they hold up to even one shot of stout recoil. I also have zero hands on experience with Leupold rings on rifles with stouter recoil than a .338 WM.

 

[Varminterror]

That is because of the design and how they are mounted not quality. Once fitted on that particular receiver and lapped they are a strong setup.

Yup. Once the end user fixes them, they’re ok. Unless they need to move them to another rifle.

Much nicer to buy quality mounting solutions which don’t REQUIRE end user correction to be useful.

 

[Gtscotty]

As for the OP, I've never lapped rings and have not had an issue until I had a set of Talley lightweights leave somewhat heavy marks on a VX-3i. With a setup using two separate rings (as opposed to a one piece), it's hard to tell if I had a problem with the rings, the receiver screw hole location, or just tolerance stack.

 

[thomas15]

A generalization for sure but it seems that the individual that takes the time to lap score rings is also going to pay attention to other details and thus do a good job with the install vs. those who just mount the rings and slap the scope on.

 

[Gtscotty]

A generalization for sure but it seems that the individual that takes the time to lap score rings is also going to pay attention to other details and thus do a good job with the install vs. those who just mount the rings and slap the scope on.

You're definitely a painting with an overly wide brush there. I certainly don't just slap my scopes on, I always torque to the prescribed values, obsess over getting everything level and generally use one piece mounts like the DNZ Game Reapers, with which I've never had any issues. Even other decent two piece mounts have been fine, but I'll keep a closer eye on Talley's and the like from now on.

 

[thomas15]

^^^ I guess you missed the part where I said "a generalization for sure..." but I forgive you as you put up an otherwise totally awesome post!

 

[Bayourambler]

I had a scope the other day that did not sit very good in the rings. I used stick back da sand paper 180 grit to lap it with the scope itself. It sits in there perfect now.

 

[I6turbo]

I'd think the sandpaper on the scope tube, being overall larger diameter, would hog the ring I.D. out to the point that it's too large to fit properly around the scope tube. It should get rid of the high spots, though.

 

[Bayourambler]

I'd think the sandpaper on the scope tube, being overall larger diameter, would hog the ring I.D. out to the point that it's too large to fit properly around the scope tube. It should get rid of the high spots, though.

It actually fits real good , you just cant get greedy. You can see the rings are clamped good with room to spare.

 

[Mowgli Terry]

See if this work. This is about alignment. Years ago a friend made me a 1" steel bar. This made from stock turned on a lathe This bar is used to align Redfield type rings on to the base(s). This bar is also used to turn in the front ring keeping the scope from being a wrench. I'm not sure my eyes are good enough to line up the points.

 

[hdbiker]

After finding some scope damage from scope rings, I started laping rings while up grading to better scopes. Easy to do and the tools are fairly inexpensive. hdbiker

 

[Skylerbone]

Having just read beginning to end the full thread there are some key elements I absolutely agree with.

First on Leupold: I own a half dozen because they’re cheap but decent visually speaking (glass quality and brightness) for hunting scopes and that is what my focus is. Rarely do I need more than a 50 yard shot but have had occasion to reach out to 200 yards. That’s not a difficult shot for anyone with a small amount of practice.

Back to is it necessary? For most of us probably not. We buy cheap scopes, we don’t dial up and down much and probably never correct for windage (excluding Kentucky) after zeroing. Any $50 optic will probably do if used during daylight hours and we can “upgrade” 3 years later when something goes wrong.

Is it better to align and lap to prevent damage and increase contact? Well I think the math works out to a resounding yes, without question (excepting lapping of those with inserts). Even the best 1-piece mounts with perfect alignment (which they don’t really have) and good contact are subject to stress when tightened to a receiver which may not be so perfect.

Numbers don’t always prove the point you champion. In my career, I provide all of our facility’s tours to the public. One recurring group is a science class from a local college studying environment. When I explain that combined flow raw sewage is 99.5 % pure water vs. their “ultra purified” bottled water which proudly professes that same spec, well, their faces tell the tale. The point I make to them is that advertising numbers sound great but reality is harsh even when discussing a “small” amount of allowance. We all agree that none of us want to drink sewage despite it being “pure enough” and that precision really does impact the quality of a finished product. We prove that point in the lab at the end of the tour.

Shooter’s choice on whether you do or don’t include these steps but realize what you believe you know is limited by your sphere of knowledge and many, myself included, live in a very tight bubble.

 

[Slamfire]

Yes and they act like its not a problem.

Ruger allows much larger tolerances than I consider acceptable. My 35 Whelen Ruger #1 had always been misfiring and I could see that the firing pin hit was well off center. I sent the rifle to Ruger. Their rejection criteria is 40 thousandths. My rifle was between 25-30 thousands so the Technician was not authorized to do anything. And, they fired 20 rounds and they all went bang, but my rifle would easily misfire in 1:60 rounds, sometimes more, and twenty rounds down the tube is not enough to pick up marginal ignition. You can look on the web, but my recollection is that the Army determined 0.015 to 0.020 as their limits for firing pin offset, any more, and the weapon might misfire. Ruger's limits are therefore huge.




The Tech was a great guy, very knowledgeable, he checked the copper indentation of the mechanism, and he was sympathetic enough to do a quick and dirty. He installed a part that lifted the block up a bit, and that seems to have helped. I only fired around seven rounds but they all went bang and the firing pin hit is much closer to center. He was probably not authorized to do even that, because the eccentricity of the firing pin blow was still within Ruger acceptance criteria.

 

[taliv]

In May

I started lapping my rings when I upgraded to higher quality scopes. I was very surprised all of my ring bases were not contacting the scopes, by as much as 1/2. Lapping is simple and easy and the basic tool to do it cost about the same as a set of dies and will last a lifetime. Easy er on the scopes with better ring contact. hdbiker

In June

I started lapping rings as I upgraded to better scopes. I was amazed at how little contact there was on some of them. Lapping tools are cheap compared to the price of a good scope. I've seen scopes damaged by miss aligned rings. hdbiker

November

After finding some scope damage from scope rings, I started laping rings while up grading to better scopes. Easy to do and the tools are fairly inexpensive. hdbiker

What’s the old saw about not needing a good memory if you tell the truth? Good to see your story isn’t changing

 

[cheygriz]

I always lap rings. I don't know of any other way to get precise alignment.

To me, it's well worth 30-45 minutes of work to know my alignment is exact.

 

[oldfortyfiveauto]

https://www.midwayusa.com/product/485115/burris-30mm-signature-zee-weaver-style-rings-matte

All the issues go way with the z rings. I use them exclusively if they will work on the gun/scope combination.

 

[Garandimal]

I line the rings with 3M electrical tape.




GR