How to check if you need to Lap?

Tesoro

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I have some new talley one piece 30mm alloys coming in a few days. I have never had any probs with them before but decided to check if they need lapping as the scope is expensive and maybe I lucked out with the other sets. I have about every amateur gun smithing tool you can buy other than a lapping kit.

Its going on a H-S 2000 action so not worried about that part.

Is there an old school trick to check alignment and % contact of the scope body with the rings?
 

J E Custom

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In my opinion, Save your money.
Good rings and bases do not need lapping. If the site base screw holes are not straight, that Is another problem and should be dealt with separately.

If you assemble everything without tightening and get the correct fit, tighten the rings first (This keeps the ring from rotating out of alignment) And any slack in the system is taken up between ring and bases and prevents maring a fine scope.

If you want a scope ring reamer, I have a brand new one that I have never used and will make you a good price for it. (I bought it before I knew to buy good quality rings and bases).

J E CUSTOM
 

martinakl

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I researched this a while back. The Talley one piece, aluminum, one piece, will have enough flex to adjust ever so slightly.

While researching, I picked up a trick: Rubber cement on the inside of the rings (top and bottom). Clamp them down, let it dry, and clean up the stuff that oozes out. It'll make for 100% contact.

A secondary benefit I've found is that it helps with ring marks, when you remove the scope.
 

tbrice23

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Go get a lapping bar !
Use it !

If you think you have a perfect, lap a few strokes the you'll know bad it REALLY is.

Otherwise get a quality one piece base and Burris Signiture rings, they have self aligning bushings.
 

phorwath

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The best method I've read about for correcting scope tube to scope ring fit is promoted and presented by Jim See.
He's the gunsmith that initially manufactured and marketed the Muscle brake muzzle brake.
I think an wrote an monthly article that was recently covered on this (Men's) website.
Short version is Mr. See glass beds the scope tube to the lower ring half for the perfect contact fit between the scope tube and lower scope ring. Same principle as glass bedding an action to a rifle stock, except much simpler and very little time involved.
I haven't used his method yet, but intend to on each and every scope I mount in the future.
Check the prior monthly articles on this website. Or Google Search Jim See scope mount. He has a website of his own and the scope mounting method is also provided on his website.
Slicker than sliced bread. Another advantage is the epoxy bedding reduces the slippage of the scope tube in the bedded scope ring.

I own and have used a lapping bar and lapping compound to improve scope tube / ring fit and ring alignment multiple times. That method is prehistoric compared to simply bedding the tube into the lower ring half.

Also (another advantage), the bedding method leaves the lower scope ring surface in factory new condition, preserving the full resale value, compared to the value of used, lapped scope rings. I don't mind purchasing lightly lapped scope rings because I own the lapping bars. Many won't purchase used rings that have been lapped.
 
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Tesoro

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I use Talley rings I guess because I just have a bunch and prefer to deal with one smaller company. They look me up when I call and note this guy is a good customer so we wont charge him to send out a pack of new screws or will send me a new ring top for free if I gouge one in the field. etc..

Anyhow I was at the range the other day and some guy next to me had a new swaro x5 mounted on talley lightweights. I said hey nice scope I have the same setup. We chatted and he told me he had checked the rings and lapped them because they surprisingly only had 40% contact. He was an aircraft mechanic but noticed he was not that experienced in shooting. I figured he was FOS but got me to worrying anyhow as I had a new set on the way!

The Talley guys told me no way do I have to lap their rings. The flex part makes sense. I usually do clamp my rings and then do the base second, even tho I cant torque the base screws but its not that critical as its steel on steel with some blue glue.

The rubber cement trick makes sense. I'll try it as cant hurt but just help.
 

jrock

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All the Talley Light weight's I've mounted had very little contact prior to lapping. I don't want rings to exert a flexing force on my expensive scopes so I lap them. I also lap Leopold rings as well. I switched to rails and TPS rings and never had to lap. I honestly hate lapping as its a pain. Next time I use Talley's, I might try bedding them vs. lapping. Lapping aluminum isn't nearly as bad as steel. I would vote to try bedding steel rings before lapping.
 

tbrice23

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Rubber cement?

What if it really does hurt. If your scope only has two or three points of contact with solid scope rings and the rest laying on a flexible surface, what do you think happens under recoil... every shot. I'm not sure but it sounds slightly better than Hubba Bubba bubble gum.
Just do it right before you damage your scope or its finish.
I'm trying not to be a smart ***, just trying to help. I see people work VERY hard at being lazy, it kills me.
Again not being argumentative just trying to help.
 

jrock

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$100 for a lapping kit vs. damaging a $1200+ scope is a good investment to me. The sales on them are pretty good as well. Shop around.
 

tbrice23

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Brownells
Screenshot_20180404-131937.png
 

Barrelnut

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The Wheeler lapping kit has alignment bars that will show you just how much your rings are out of alignment. Then you can judge IF you need to lap or not. You can get a kit with 1" alignment bars or 30MM bars or both. This way you know just what you need to remove too (if anything). It's a small investment for a $12000 scope.

I also use Burris Signature rings. They are awesome. Won't mar the scope and allow you to make adjustments if the scope happens to not align with the bore very well.

I also use rosin on my scope rings before installing the scope. Just dust some on top and bottom of the rings. I have never had a scope slip with rosin. If you have ever used rosin in a barrel vise you would understand why rosin works so well.
 

martinakl

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  • 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.

http://www.talleymanufacturing.com/About/Frequently-Asked-Questions-(FAQ).aspx



***Full disclaimer, I've lapped Talley rings, among other brands of rings. I'm not against it. As they say, More than one way to skin a cat.
 
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