lapping scope rings (not lap dancing)

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nagarifle
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lapping scope rings (not lap dancing)

Post by nagarifle » Wed Feb 23, 2011 9:12 am

some say that lapping the scope rings helps in accuracy. now i think that it would help to remove any rough spots on the rings thus avoiding damage to the scope tube. this smooth outs the rings for a better fitting of the scope.

has any one done this, what is your experience before and after lapping? what method used?
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Re: lapping scope rings (not lap dancing)

Post by dr.jayakumar » Wed Feb 23, 2011 9:26 am

i did some on my scope rings to fit the scope securely,but i don't know whether it helps accuracy.it sure helps a tight fit for the scope,no loosening at recoil thats all i could asume.

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Re: lapping scope rings (not lap dancing)

Post by nagarifle » Wed Feb 23, 2011 12:20 pm

dr.jayakumar wrote:i did some on my scope rings to fit the scope securely,but i don't know whether it helps accuracy.it sure helps a tight fit for the scope,no loosening at recoil thats all i could asume.
how did you do the lapping? what stuff did you use?

thanks
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Re: lapping scope rings (not lap dancing)

Post by brihacharan » Wed Feb 23, 2011 3:11 pm

Hi Guys,

> Lapping means surface grinding by using a lapping paste, usually a paste made of abrasive material such as fine carborundum.
> This procedure (lapping) is commonly used in grinding automobile valves - to ensure its proper fit in the engine.
> Although Valve Grinding machines are available to smoothen the valve surfaces - the final task is done by hand by skilled mechanics.
> Hence in the case of Scope fitment, the inner surfaces of the scope rings could be lapped if the surface is un-even which leads to improper grip of the scope - leading to 'creep'.
> My sincere suggestion would be (if you don't have steady hands) to avoid this exercise - instead put gum tapes that have adhesives coated on both sides on the scope and then tighten the rings, thus you will get a better hold / grip between the scope tube & the rings.
> Alternately you could use the tape commonly used by plumbers to tighten hoses - this tape is very thin (some sort of a cloth or paper) which works effectively.
> Proof of the pudding - I have used it successfully in mounting my Walther 4 x 32 scope on to my air rifle, which was creeping due to the after shock when fired, common to spring piston air rifles.
Good Luck
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Brihacharan

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Re: lapping scope rings (not lap dancing)

Post by MoA » Wed Feb 23, 2011 3:25 pm

I have lapped scope rings in the past. And even used super glue to ensure the scope will not move post seating. Did it on my .300 WM originally. Did it make a difference? Not that I could tell.
I now use decent scope mounts, like the NightForce mounts, and dont bother with lapping or tapes, or glue. I torque the rings to 15 lb/in using a torque screw driver. Dont have any issues with the scope moving.

getting a lap dance on the other hand is whole different ball game so to say. Personally am not a fan.. at least of professional lap dances.

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Re: lapping scope rings (not lap dancing)

Post by z375 » Wed Feb 23, 2011 3:50 pm

Naga,

I assume you need to do this for standard 1" scope rings. You will need a 12" steel round bar stock that is perfectly straight and concentric and has an outside diameter of 1.000", some use .996",but a bar diameter of 1" is commonly used for 1" scope rings and 30mm bar dia. for 30mm rings, you will have to weld/tap a suitable handle into the middle of the bar and make a few light cuts on the bar spaced 1/2" away from each other. Once the lapping bar is ready, buy some good quality valve-grinding compound (Carborundum International) preferably in fine grit, coarse is rarely used and not recommended. Assuming the top half of the rings are removed, load up a small amount (peppercorn size) of grinding compound onto the bottom half of the rings and place the lapping bar in the lower halves as you would with a scope, you will have to now work the lap back and forth in a figure "8" fashion between the rings as this will cover more areas that need tending to and will give you even results. The whole idea here is to achieve 75% contact or more between scope and ring thereby giving you better alignment the reducing/eliminating stress on the scope tube, you can use your judgement to see how much area has been abraded and is now making proper and even contact with the scope.

Some folks lap the top halves too by loading up compound on the lapping bar and then installing the top halves and tightening the screws just enough to give a snug fit on the bar but not impede its movement whilst lapping. Just doing only the bottom halves of the rings has always worked for me, so I hope this helps you too!

p.s- Kokopelli, Wheeler Engineering and Sinclair International sell scope lapping kits too, but it don't take no rocket science to make one!
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Re: lapping scope rings (not lap dancing)

Post by nagarifle » Wed Feb 23, 2011 4:24 pm

thanks gents, for the info. i use the red rouge as its cheap and locally to be had, it would apper the on the low end of scope rings it might help to help but should not be needed on the higher end of the scope rings market.

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Re: lapping scope rings (not lap dancing)

Post by eljefe » Wed Feb 23, 2011 5:26 pm

Yup, if you run out of patience and precision-you can 'skin bed' the rings.Whats the scope and calibre?
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Re: lapping scope rings (not lap dancing)

Post by dr.jayakumar » Fri Feb 25, 2011 11:13 am

nagarifle wrote:
dr.jayakumar wrote:i did some on my scope rings to fit the scope securely,but i don't know whether it helps accuracy.it sure helps a tight fit for the scope,no loosening at recoil thats all i could asume.
how did you do the lapping? what stuff did you use?

thanks
had used a wooden dowel wrapped with abrasive paper.had done with my hand.no rubbing compound or machinery used.sharp edges where filed out.it seems easier than machine work and saves time.

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Re: lapping scope rings (not lap dancing)

Post by brihacharan » Fri Feb 25, 2011 11:32 am

dr.jayakumar wrote:
nagarifle wrote:
dr.jayakumar wrote:i did some on my scope rings to fit the scope securely,but i don't know whether it helps accuracy.it sure helps a tight fit for the scope,no loosening at recoil thats all i could asume.
how did you do the lapping? what stuff did you use?

thanks
had used a wooden dowel wrapped with abrasive paper.had done with my hand.no rubbing compound or machinery used.sharp edges where filed out.it seems easier than machine work and saves time.
Hi there,
> You need steady hands to lap the insides of a scope ring to ensure an even surface.
> As far as accuracy goes its all about:
1. Your steady hold
2. Quality of the barrel rifling
3. Perfect scope 'zeroing'
4. Quality of the pellet / perfect fitment in the breech
5. Trigger pull - it should be smooth with even pressure - no sudden pulls
Cheers :D :D :D
Brihacharan

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Re: lapping scope rings (not lap dancing)

Post by winnie_the_pooh » Fri Feb 25, 2011 11:56 am

Naga,

Get these and there is no need for any of this

http://www.opticsplanet.net/burris-rifl ... rings.html

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Re: lapping scope rings (not lap dancing)

Post by brihacharan » Fri Feb 25, 2011 12:45 pm

winnie_the_pooh wrote:Naga,

Get these and there is no need for any of this

http://www.opticsplanet.net/burris-rifl ... rings.html
Hi there,
> That is a good info pal!
> Are these available in India? If so where?
Cheers
Brihacharan

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Re: lapping scope rings (not lap dancing)

Post by nagarifle » Fri Feb 25, 2011 12:54 pm

gents thanks for the info. i do not see myself doing any lapping around :lol:

i posted the tread to see who and what info people have to share with others as this subject seems not be covered.

i use high quilty rings and mounts so that takes care of wasting elbow grease :D
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Re: lapping scope rings (not lap dancing)

Post by winnie_the_pooh » Fri Feb 25, 2011 1:14 pm

Hi there,
> That is a good info pal!
> Are these available in India? If so where?
Cheers
Brihacharan
[/quote]

No.Like all other things you need to get them from abroad.

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