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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 13:12
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just received my IOR today, cant wait to mount it. However, I have never mounted a scope before, i have all the instructions with the torque specs and it seem pretty simple and straight forward. up till the point about lapping. what exactly is lapping, does it need to be done, and how do i do it? i have a tps 20 moa base and tps low steel rings its going on a 700 ltr. any advice is greatly appreciated, so is honesty, if this is something that should be left to a proffesional so i dont damage any equipment let me know please. thanks alot

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I say no lapping needed with the TPS rings. They are "pre lapped" from the factory.

The two sets of of TPS rings I own are good to go.

 

BUT....On the other hand, those that swear by ring lapping will say to do it because the factory receivers like your Remington are most likely not square and lapping will help rectify that.

This theory honestly has nothing to do how good the rings are, and everything to do with how square your receiver is. 

 

Up to you. I never have lapped any TPS or Badger Ord. ring have have gotten along fine.

I say ring that scope and shoot it....

 

I'll PM TPS Phil the link to this thread and he can give his input as well.   

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 14:10
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I have never lapped a set of TPS Rings, but Cheaptrick is right and someone will say to do it....

 

I say put her together and go shoot.....

 

Phil

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 14:15
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Hey Phil, will lapping TPS rings void the warranty??

Like Badger??   

 

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 14:44
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Yes,

 

Also this is what I never get, when this topic comes up....

 

Here you have rings with the tightest tolerances on the market and you lap, because the action is off....

 

Now your rings are off, because you lapped them out of there high tolerances and if there is any problems you blame the ring mfg?

 

Why not go after the rifle mfg, as you know there is a problem from the get go?

 

I haven't lapped a set yet and I have no ring marks or any other problems.....

 

I have one guy that says his scope slid under recoil, so he lapped his rings (which you lose the tolerances) and torqued them more and it doesn't slide?  Makes no sense what so ever....

All he had to do is read the instructions and follow....

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 14:51
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Originally posted by TPS_Phil TPS_Phil wrote:

I have one guy that says his scope slid under recoil, so he lapped his rings (which you lose the tolerances) and torqued them more and it doesn't slide?  Makes no sense what so ever....

All he had to do is read the instructions and follow....

 

 

Yeah, I think I saw that thread also....

 

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 16:55
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In my opinion:

 

1.) Bed your base to the top of your action.  http://www.snipercentral.com/forums/viewtopic.php?t=11315

2.) Finish mountng the base.

3.) Install the rings and test with a lapping alignment kit to see if lapping is needed.

4.) If it all ligns up properly mount it up.  If it doesnt lign up properly then lapping is needed. 

 

TPS rings are great from my experiences, but there are so many other things that could cause rings to not line up exactly that sometimes lapping is needed.  Just becase rings are slightly out of alignment doesnt mean that it is the rings fault.  Your action, base bedding job, or base could have issues.  I say test for exact alignment yourself on your rifle to get the real results. Until you check YOUR equipment you won;t know if it is truly needed. 

 

Here is my experience: http://www.snipercentral.com/forums/viewtopic.php?t=11481 

 

Further, you should bed your base before you bed your rifle.  You want your rifle bedding done under the EXACT conditions you will be using it under.(base torque)

 

Adam



Edited by Adam132601
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 17:10
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Bedding the rail can also be accomplished, per Badger Ordnance instructions, using Blue Loc-

Tite.

I did it that way on a factory Remington Varmint Synthetic years ago with no problems to report.

 

Not knocking Adam's recommendation, I'm just saying my stuff hasn't needed anything else.

 

 

 



Edited by cheaptrick
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 17:24
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What would the procedures be for bedding with blue?

 

Cheaptrick,

 

After we beat LSU this week and win out the rest of the year, I forsee another repeat.  :)

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 17:32
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http://www.badgerordnance.com/folders/downloads/3/Mounting%2 0rings%20and%20bases.pdf

 

This is not the bedding procedure you recommended, but it's worked for me for a good while.

All this really accomplishes is keeping water from wicking up underneath the rail.

 

Here's the proof.

5 shot 100 yrd group on a factory rifle. She measured .382.

 

 

 

 

Yeah, I hope your right about the Gators Saturday, Brother. I'm not so sure.....Gator "D" is weak this year. LSU will run and throw on them BIG!!

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 18:18
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Keep in mind one other thing here...

 

The rings could be technically perfect and the rifle receiver could be perfect as well, with perfectly aligned base mount holes, and lapping could still be needed.  How?

 

Picture this...  The top of a Rem 700 (I'll use that as an example) receiver is round/radiused.  The bottom of the bases are radiused to match the receiver.  Therefore, the bases are free to slide back and forth radially along the top of the receiver.  What locates the bases at 12:00 directly on top of the receiver?  Nothing but cap screws, which are not a method for precision locating anything, nor can they be, unlike ground dowel pins that are held to much tighter tolerance on diameter.  The reason for this is because there has to be clearance in the screw holes of the bases for the screws, otherwise you wouldn't be able to turn the screws, so base location can technically deviate from true top dead center of the receiver by half the amount of the total clearance between the screw holes in the bases in either direction.  Plus, there are acceptable variations in the diameter of the cap screws.  If the cap screw is smaller in diameter than the screw holes in the bases -- and they have to be -- then clearance = radial "play." 

 

Additionally, there is a min and max tolerance limit on receiver diameter, just as there is a min and max tolerance limit on the matching radius on the bases.  The base manufacturer has to take the receiver tolerance into account, otherwise, some bases won't properly fit some receivers.  Imagine combining a receiver made to the lower side of the tolerance on diameter and bases made to the upper limit on radius size.  The ring i.d. is made to within an acceptable +/- tolerance, as is the location features between the base and rings.  Then combine mount base holes on the large side of the tolerance with cap screws made to the small side of their tolerance, and it's easy to see that even if the screw holes are in perfect, dead center 12:00 alignment on the receiver (which is usually not the case), you have built-in play due to the combined tolerance stackup of all components and mating surfaces, yet the bases, rings, and the reciever could all still be in tolerance.

 

As for lapping "opening up" the ring i.d., taking them over the max tolerance, this isn't the case, because you aren't removing much material with lapping, you're only removing the "high" spots and squaring up the centerline of both rings to match the correct orientation of your setup so that the rings don't stress the scope tube.  And, since the typical lapping bar is made to a pretty tight "+0 / -XXXX" unidirectional tolerance, it isn't larger in diameter than the scope tube and the gap between the ring halves more than compensates for the difference.  Plus, once you have more complete contact with the scope tube, you're actually getting better ring grip on the scope tube than before, without high spots.

 

I don't care whose rings you use or how high quality those rings are made.  As long as you're using 2 piece bases, sometimes lapping will be beneficial, if not downright necessary.

 

Having said all that, most of the time, you can get by o.k. without lapping, because the amount of misalignment between the rings may be no more than a couple 0.001".  However, ANY misalignment causes you to have to use more of the scope's W/E compensation than you would otherwise, and in cases of gross misalignment, you can actually degrade the optical performance of your scope by slightly bending the tube, forcing optical components out of alignment with each other, and/or your W/E adjustments might not track properly.  Lapping also removes minute burrs on the edges of the rings, which is one cause of ring marks.

 

If you don't mount very many scopes, then by all means, mount everything up and go shooting, and if you're able to zero the rifle without too much W/E correction then forget about it.  However, if you do mount quite a few scopes, you'd be well-served to buy a lapping kit in 1", 30mm, or both, as they aren't that expensive, lapping isn't hard to do, nor does it take long to do.  I look at it this way... if lapping gives me peace of mind that my rifle/scope/mount system is installed as perfectly as I can get it, and it only took 20 min or so of my time to get it that way and forevermore it's perfect, and doing so caused me to use up less of my scope's adjustments, I say it's worth it, even though the rings may have been only a couple 0.001" out of alignment otherwise.

 

The reason a scope mount manufacturer wouldn't stand behind rings that have been lapped is because it involves modification to their product they didn't perform and therefore have no control over.  But, I can assure you that properly lapping rings won't hurt anything, and in fact, can only help.  Even if your misalignment is only 0.001", if lapping the rings removes that 0.001" misalignment, isn't that technically "better" even if the original misalignment didn't cause any noticeable problem?  If lapping wasn't beneficial, then gunsmiths and accuracy freaks wouldn't bother with it, scope manufacturers wouldn't recommend it, and nobody would offer lapping kits for sale.

 

But, as always... your mileage may vary.

 

Good shooting there, Mark!



Edited by RifleDude
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 18:54
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Well stated, Ted. Certainly a lot there to think about.

 

2 piece bases are more prone to misalignment error than a 1 piece rail, so I prefer the latter.  

 

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 19:48
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Originally posted by cheaptrick cheaptrick wrote:

http://www.badgerordnance.com/folders/downloads/3/Mounting%2 0rings%20and%20bases.pdf

 

This is not the bedding procedure you recommended, but it's worked for me for a good while.

All this really accomplishes is keeping water from wicking up underneath the rail.

 

Here's the proof.

5 shot 100 yrd group on a factory rifle. She measured .382.

 

 

 

 

Yeah, I hope your right about the Gators Saturday, Brother. I'm not so sure.....Gator "D" is weak this year. LSU will run and throw on them BIG!!

 Mark- too bad you hadn't taken the time to lap the rings on that rifle before you fired that group; you might not have gotten quite so much vertical stringing if you had...  



Edited by RONK
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 20:15
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Originally posted by RONK RONK wrote:

Mark- too bad you hadn't taken the time to lap the rings on that rifle before you fired that group; you might not have gotten quite so much vertical stringing if you had...  

 

 

That's not the best group I ever had out of Black Betty...but they'll do.

I have seen some pics of some groups here and abroad that are much better than mine.... 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 20:39
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 Actually, this is one of those rare and delightful threads in which I can agree with pretty much everyone who posted. (So far, at least! ) Yes, it can be beneficial; No, it probably isn't necessary.  I guess I have to lean toward Rifle-Dude's philosophy. (EXCELLENT, well-worded post BTW! ! )

 I liken the practice to precision handloading. I believe that it can often help to"lock" all the components a little tighter into a cohesive unit, especially when used along with base- bedding, etc.

 TPS Phil- It isn't really a matter of "opening up" tolerances on high-quality rings (such as yours') as much as it strives to Axially align the rings' inside, tube contact surfaces to one another, after they are tightened to the base, and to get the ring surfaces into 100% contact with the tube. For the reasons given by Rifle Dude, they are never quite perfect, although a one-piece base helps alot.

 It really is a time-tested practice in  machine shops to "lap -in" precision tool parts to achieve the highest possible degree of fit, and this is what we should be trying to aquire.

 BTW, I personally have no problem whatsoever in believing that someone had a scope sliding in the rings and was able to fix it by lapping them into full contact. I don't recall that thread though, so I don't know the particulars on that one...

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/01/2007 at 20:42
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Originally posted by cheaptrick cheaptrick wrote:

Originally posted by RONK RONK wrote:

Mark- too bad you hadn't taken the time to lap the rings on that rifle before you fired that group; you might not have gotten quite so much vertical stringing if you had...  

 

 

That's not the best group I ever had out of Black Betty...but they'll do.

I have seen some pics of some groups here and abroad that are much better than mine.... 

 

  Yes they will. That is some very good shooting.

 

 Incidently, whenever I see "abroad"  who's much better than mine, I have to be real careful not to let her catch me staring at it!  



Edited by RONK
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/05/2007 at 21:04
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No need to lap here....but then I don't use two piece bases....If the base is one piece and not defective, I can't see a reason to lap quality rings....however is the rings aren't perfect or the base isn't true....then I can see a reason...but if the base is one piece and maintains the rings on the same plane irrespective of the mounting to the receiver holes and the rings are quality and aligned....I only see lapping as a OCD function of someone who is sure "things won't be right unless I adjust them"....then wash my hands  20 times and count backwards while tapping my foot....I think Rifledude is righton though....unless you just go crazy on it....it won't do any harm either....after mounting the one piece base, I set the bottoms of the rings in place and torque them down....I then lay the scope body in place and play with the eye relief and positioning.....if it seems to lay down without binding after pushing it forward and backward....I don't worry about it.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/06/2007 at 10:40
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Originally posted by sandsock sandsock wrote:

No need to lap here....but then I don't use two piece bases....If the base is one piece and not defective, I can't see a reason to lap quality rings....however is the rings aren't perfect or the base isn't true....then I can see a reason...but if the base is one piece and maintains the rings on the same plane irrespective of the mounting to the receiver holes and the rings are quality and aligned....I only see lapping as a OCD function of someone who is sure "things won't be right unless I adjust them"....then wash my hands  20 times and count backwards while tapping my foot....I think Rifledude is righton though....unless you just go crazy on it....it won't do any harm either....after mounting the one piece base, I set the bottoms of the rings in place and torque them down....I then lay the scope body in place and play with the eye relief and positioning.....if it seems to lay down without binding after pushing it forward and backward....I don't worry about it.

 

 Well, if the one-piece base is perfect when you purchase it but you then mount it on a mis-drilled or mis-aligned receiver and tighten the screws, guess what ? ( No, it isn't going to pull the receiver into spec!....)

  I agree with you though that you can usually get a good idea of how well they fit up when you lay the scope into the lower ring "cradle" and move it back and forth. When it is right, it will feel right.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/06/2007 at 10:49
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lapping and bore cleaning are identical-- start with clean rags, then they can go anywhere. the fact that so many people do both so differently and get good results, pretty much speaks to the need of any specific method. coming from an era when lapping was necessary the current products offered and the degree of the quality by the manufactures is amazing.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/07/2007 at 00:14
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I have never lapped a set of TPS rings, however I have lapped my share of other types of rings. I will say that it has no effect on accuracy that I can see, all it does is prenvent damage to your scope tube if you have a out of square receiver...
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I'm tracking but if a one piece base misaligns on the receiver, the scope can be mechanically compensated when zero'd.  On a two piece base, lapping is going to be almost always necessary as you now have the effect of two different planes and not only may the scope be totally catty-whompiss but the tube will probably bind and a bunch of other bad things....I gave up on two piece bases as a teenager, they are not worth the trouble.  When through manufacturing the rings have high spots that cause the tube to bind, that's where lapping pays off for a one piece base.  When I've found radius issues on my receiver to scope base, I use a bit of epoxy to smooth things out.  I'm not saying lapping is unnecessary, but I've observed a lot of people do it when it wasn't probably needed (but then it really didn't hurt anything either).
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/07/2007 at 19:36
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If you use 2-piece bases, lapping is still unnecessary if you use a ring/base combo designed to self-compensate for misalignment, such as the Burris Signature (and any other ring design using ring inserts such as Sako Opti-Lok), S&K, and to some extent Conetrol.  The fact these designs exists is evidence that at least some misalignment exists to some degree with most 2-piece mount setups.  I've lapped a lot of rings, and I have never seen a set of rings that were in 100% perfect alignment after installation... never!  You can easily see this during lapping, as when you start lapping, you will see uneven cleanup on the i.d. of the lower ring halves.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: October/08/2007 at 12:05
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i am going to sears to pick up loctite and a torque wrench today, i will probably mount the base to the receiver and the lower rings. then ill lay the scope in if it lays in and can slide with out stressing the tube ill probably pass on the lapping. atleast until ive put a few rounds down range. i noticed a few people had mentioned vertical stringing as a a result of a stressed tube or unsquare mount. what exactly is verticle stringing so i can spot it at the range if it happens? also what is a good distance to test at? i plan on using a 100 yd zero. thanks again

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You may not find a torque wrench in inch pounds at sears, several internet places have them and Sportman`s warehouse stocks them.

 

Duce 

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Originally posted by remmylite remmylite wrote:

 noticed a few people had mentioned vertical stringing as a a result of a stressed tube or unsquare mount. what exactly is verticle stringing so i can spot it at the range if it happens? also what is a good distance to test at? i plan on using a 100 yd zero. thanks again

 

Remmylite,

Vertical stringing is when your groups on target tend to be much longer vertically than horizontally.  Horizontal stringing is just the opposite -- group dispersion that's much wider in the horizontal than vertical.  In general, your groups should be close to the same width in all directions, or approximately round in shape.  Occasional stringing could occur just by sheer luck, but if your groups are usually much wider in one direction than another, this usually indicates a bedding problem.  3-shot groups aren't a good indicator of whether your rifle is stringing shots, because one of the shots could be a flyer from an assignable cause.  You really need to shoot 5 shot groups to truly get a good idea of how well your rifle is grouping.  100 yards is a good, realistic distance to test loads in your rifle and get a good idea of how your rifle shoots.  It's a good zero distance as well (for hunting, that is), though I think 200 yds is a better distance to zero at, as it gives you a longer point blank range, and yet your POI will only be between 1-2" high at 100.



Edited by RifleDude
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