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G1–G7: Nearly had a heart attack!

I personally think lapping is a legacy procedure that holds on from an era when it was useful. I always assumed it was a necessary step until I read an essay once about the precision of modern machining and the author posed the question of why people think they are going to be able to improve upon the precision of modern CNC machining equipment with a manual hand held lapping device that requires the motion of a human arm for its precision? That kind of logic appeals to me and as I thought about it I came to the conclusion that I could not do better than a precision CNC machine by using a hand held lapping device so I do not lap any of my rings. (I am basing this discussion on the assumption that the lapping tools used are the manual hand operated type. If there are CNC lapping machines then those would not cause the problems that I posit, but I still feel they would be unnecessary.) I do, however, buy good quality rings and good quality one piece mounts and I concede that if you buy cheap rings or use two piece mounts it is possible that if they are out of spec enough then lapping might be able to improve things. But there really is no excuse for even cheap rings to be that out of spec with today's modern equipment.

So I am speculating that in generations previous to my own, lapping was a very common and useful exercise in precision shooting that has held over due to our desire to be able to make things better than what it was when we bought it. I think all people but especially the kind of people who get into long range shooting like to think that there are things that they do that make their equipment better. I know I have that feeling and I have to fight it at times when I realize that in today's world with all the modern technology much of what I can add will have no effect at best and more likely will actually make things worse.

Yes, I just walked all over a sacred cow. I have had this conversation before and 99% of shooters not only disagree with me but they usually start hurling insults that remind me of what I see from the lefty SJW BLM crowd. But its my opinion and it is based on interesting if not sound logic so I put it out there for consideration and hopefully amicable discussion.

CNC maching can be very accurate. But who is doing it is important. If it is an outfit dedicated to making the best product possible, they will know when to sharpen/replace cutters, they will know the quality and reliability of their CNC machines, and they will inspect everything coming off the machine at regular intervals and especially before shipping.
Joe Blow will set up and check his discount CNC machine once and run it until customers start returning parts.
There is no magic that will replace skill, caring, and customer service.
And, as other have said, you have to know if your rifle's mounting surfaces are what they should be before you mount any rings. Lipstick on a pig.
 
All this fuss over rings. If that is so important, why isn't everyone lapping the scope tube too?

Just for Shi-s & Giggles, I just mounted three brand new scopes (never used, never mounted Nightforce, Leupold, & Winchester) in my concentricity gauge. As I expected, none were anywhere near perfect. Surprisingly, the best of the lot was a $30 Winchester (rebranded Tasco) for pellet guns!

When the practice of lapping rings first started, it was done to remove burrs and paint gobs at the edges that could marr the painted finish that was used on the scope tubes back then.

Since I never had any rings like that, I've never had to Lapp them. And I have never marked a scope.

I guess I'm failing to see how rings could affect accuracy unless they stress an action. Bedding bases to avoid stressing an action makes sense to me. Lapping rings does not. Even if the rings are misaligned, they will just bend the scope. Since scopes are bent anyway, why bother. IMHO, scope stress doesn't affect accuracy or adjustment integrity. However, stresses transmitted to the action could.

I'm sorry, I am just not convinced that lapping high quality rings is required.
 
I have marked a Tasco scope. In Burris rings. That weren't lapped or bedded. I'll have to see if I still have that scope and take a pic of it if I do.
 
There has been a lot of discussion on rings, and we measure everything else. Has anyone checked the tubes? What if the tube is not perfectly round?



Thanks

The scope tube is certainly an additional point of error but I am not about to true my expensive scope tube and this can easily be compensated for by bedding the rings. This is especially crucial if the setup requires the rings to be right up against the erector assembly part of the body. Errors accumulating to the rings/tube juncture and then clamping the rings right next to the erector assembly is a leading cause of "defective" scope returns.
 
The scope tube is certainly an additional point of error but I am not about to true my expensive scope tube and this can easily be compensated for by bedding the rings.........

I doubt that lapping rings will compensate for any scope problems.


........Errors accumulating to the rings/tube juncture and then clamping the rings right next to the erector assembly is a leading cause of "defective" scope returns.

How do you know that? Do you have a report or credible source of info for that? I'm not saying that can't happen. I'm just doubting that it is a leading cause.
 
I know that bedding bases sometimes matters. Usually because the action isn't as perfect as the base.

But what I would like to see is a study by a credible shooter (maybe a benchrest competitor) of before and after lapping rings to determine the extent of any differences.
 
Seems like lapping the bottom of the rings to gain bedding compound clearance, and then bedding the scope might be the best path forward.

Or use those Burris rings with the inserts if the inserts are conformable.
 
I lap most rings and have used most everything out there. Several reason go into this. I have not found any that are perfect. CNC is amazing but not perfect so when you have tolerance stacking between action, base and rings, things can get out of shape quickly. Most production actions even in today's CNC world leave something to be desired. I regularly find when truing an action that base screws are not on top dead center and not aligned with the axis of the action. Lapping won't fix this issue in some cases but will for minor variations. More often the rear bridge is really out causing lots of problems. If you just tighten things down you add stress to the system weather it's a one or two piece base. I just won't put a 2-3+ K glass on a rifle and hope for the best. Just my thoughts FWIW.
 
Funny y'all should bring up the subject of lapping and (gasp!) bedding. I too have always thought that lapping was essential to a quality job--but then the last time I mounted a Leupold on .243, I used cut-up Coke can pieces for shims on the bases!.

I am something of a mechanical klutz--So I have been dreading having to think about the whole subject. "Self," I said, "shouldn't a set of rings that costs north of $250.00 and designed for a specific scope model and tube ("dS" is stamped right on the mount) be of close enough tolerances that lapping would not be necessary?

So this morning I ran a Google search on "lapping Talley scope rings". The first thing I came up with on the Talley site were these FAQs:

  • Can I lap Talley mounts?
We do not recommend lapping any of our mounts. Since they are machined, it really eliminates the need to do so. Since the lightweight mounts are horizontally split, you can lap if you would like.
We highly advise against lapping our steel rings. Since they are a vertically split ring, lapping can knock them out of round.
Our Picatinny rings, although horizontal split, do not need lapped either. They are a match grade ring and are perfectly round when they come off the machine.
Note: If you lap any Talley rings, it will void any return policy since the mounts have been modified.

  • Do you recommend the use of Loctite or thread locker?
Using Loctite for the screws going in the receiver is perfectly fine. We recommend using Loctite Blue 242. We do not recommend using Loctite on the ring screws.

Nothing about bedding the rings was mentioned, but I assume the answer would be the same.
I suspect I will have to bed the Pic rail, however, to the 700 action. It is level, of course with no MOA tilt. Thanks VERY much for you comments as always and best regards.

Russ
Never used Talley's I use NEAR out of Canada hand made for your action or railed action. Little pricey $850.00 for integrated 3 ring rail mount but well worth it! Any other rings are mass produced, I will or will not lap them depending on how they align all rings and mounts should be checked upon install to see if they need to be squared up and to see how they fit your scope. Not everything is perfectly manufactured either rings or scopes!
 
Silly me—I finally researched the issue (as I should have done before) and found out the G1 BC is just fine for the modern whiz-bang bullets of today—out to well past the advertised 1 said:
Interesting. The math does not add up for most cartridges. I would be concerned.
 
Original poster here:

I have read with interest (though perhaps not a complete comprehension!) all of the discussion. A couple of follow-ups:

First, a question: does it matter that the 40mm Talley setup I have in hand is a one-piece base and lower rings—that mounts on a pic rail? Might that reduce the chance of being out of line?

Second: I asked myself the same question another poster posed about why I should expect the alignment rods of the $85.00 Wheeler kit to be any more precise than the machines that honed out the inside of my one-piece Mount?

Third, looking at the Wheeler kit online, I cannot ascertain whether the alignment rods would even work with 40mm tubes.

Fourth: ARC mounts and rings seem to have a great following and approval for heavy-recoiling rifles with heavy scopes. However, some report having issues with the loose hinge pins coming out. But that APPEARS to go away after you torque down the screws. Not sure whether those of you who advocate lapping all Talleys would feel the same about ARC rings. Sounds like you would.

Best regards,

Russ
 
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The NLY reason I bought Talley mounts for myBrowning X-Bolt Pro is because they were burnt bronze Cerakoted, like the rifle. (Matchy-natchy, ya know.)

But otherwise I highly recommend buying ONE-PIECE rings from a high quality company like La Rue or Nightforce. They are precisely machined as one unit and should not need lapping. With individual rings you HOPE the rifle manufacturer and the ring manufacturer both made their parts exactly to spec.
 
Modern machinery isn't infallible. Ever heard of screw holes being off center? External dimensions of the receiver come into play as well. Unless you set up your receiver and check holes for alignment and the mounting surfaces themselves, how can you guarantee that your not stressing the scope tube? Admittedly, lapping isn't perfect. But, it will show alignment issues (if there is any).
Well put.
And CNC machines use all the tolerance they are allowed.
When the CNC machines in our shop screw up....they go to the Manual Machines to fix them.
I think it was the 90s H&H set up CNC to build a cheaper line of weapons........all state of the art.
Didn't work out well........they didn't want any manual work done.
 
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