Do you lap the whole ring or just bottom half only

[gslinger]

Son in law just bought a new tikka lightwieght in 7mm rem mag.
He bought a vortex pst 4-16x50 gen 2.He got Tally 1 piece base and ring set.
When I checked with alignment pins,they were way off.
He set up lapping bar and put the top half of the rings back on.
I said I think that's wrong.You should only lap the bottom half of rings.
We checked on you tube and all the video's showed them lapping with the top half on.
The way I understood it, was the top half has screws and a hole, The hole is bigger than the screw and makes it loose and it will self center the scope on the bottom half of the ring.
The top half does't need to be lapped. It has play in it. If you lap the top half too much. The rings may become to loose and there will be no gap between the rings to lock the scope in the rings, before the rings line up.
If the bottom half of the rings are not lined up, It's the top half that centers the scope and puts stress on the scope tube.

The rings are made to fit the scope tube perfectly. They will be 30mm rings on 30mm tube.
If you lap only the bottom.It will not be a 30mm anymore.
The top half will still be 30mm and fit the scope tube like a glove.It will still center the scope tube to the bottom of the enlarged ring.
If the bottom halfs are lined up. Then the top half locks the scope in tight, with lots of contact and no stress on the tube. Because
the top half is untouched and still 30mm.

We decided to lap only the bottom.
We reversed the alignment bars and put a scope ring on one bar and tightened them to specs.
The ring wouldn't pass from one bar to the other.
We lapped the bottom And set it up again. This time the ring passed with some force .Lapped again and this time the ring passed with a small bump. We lapped again and the ring passed easily'
Tighten rings to spec,and there was still a good gap between rings

Do you lap the whole ring or just the bottom half

 

[Deputy819]

For your consideration:

Scope mounting: Should I Lap or Bed my Mounting System?

Scope mounting: Should I Lap or Bed my Mounting System? By Jim See The picture is of a very expensive action and a bolted and pinned on rail from the same company. On top of it is a precision ground parallel. You can clearly see at the back of...

www.longrangehunting.com

 

[waveslayer]

I'd sell the Tally rings!!!!! Get some good rings, lapping shouldn't have to be done if you buy reputable rings.
Buy a pair of
Seekins
NF
Badger
ARC
Spuhr

Don't waste your time lapping

 

[will1588]

I have always known to lap with the top of the rings on.

 

[will1588]

I would agree with waveslayer. Nowadays most good rings are cnc precision made and don't need lapped.

 

[martinakl]

Had a local store owner that was pretty well known for mounting scopes (for what ever that's worth). For Talley's (aluminum) he would only do the bottom because he said the tops had plenty of flex in them to adjust to scope. The bottoms don't really flex. He mounted a few scopes for me with those one piece Talley's. Never an issue and never had scope ring marks when removed. I read bad reviews on here but I've never experienced any issues myself.

I use pic rails now so it's easy to move scopes around. I can't leave anything alone.

*For steel rings he did top and bottom.

 

[adam32+P]

Only lap the bottoms.

Nothing wrong with Talleys. Don't believe everything you read on the interwebs.

 

[Reelamin]

Something is wrong for sure. I have numerous Talleys and never had a problem. Only thing I notice is they have a milled groove dead center over the receiver. On a round receiver Savage, Defiance I can see just a tiny sliver of light. Defiance said not an issue. Talley (of course) said not an issue. I put a drop of silicone just to help keep any moisture out. Oh, I have never spent more than $60 on bases and rings combined or one piece sets. I mount about 5-7 new set ups a year now, and in my busy years probably 20-30. Never had a problem or had to do anything until I used a DA torque driver set at spec weight and then I fixed it with the two finger tickle. I never lapped one dang ring from any company in the last 40 years.

 

[Ucsdryder]

Love some lightweight Talley rings.

 

[Bob Wright]

I think it's correct either way. I've never had one go bad. And lapping is only removing a small amount, mainly the high spots and when it's cleaned up it's negligible on the amount of stock you've removed. Don't sweat it.

 

[Varmint Hunter]

I'd sell the Tally rings!!!!! Get some good rings, lapping shouldn't have to be done if you buy reputable rings.
Buy a pair of
Seekins
NF
Badger
ARC
Spuhr

Don't waste your time lapping

And what if the receiver isn't milled perfectly or the holes aren't dead on?

 

[shortgrass]

Some put way too much faith in "CNC Machined"

 

[gslinger]

Got a 1 piece mount in the mail.
Got the bars and rings and set up test.
Put mount on picitiny rail.
It lines up without lapping
I can pass the ring from bar to bar easily.

"Some put way too much faith in "CNC Machined"

I agree with this.
When we lapped the rings on my son in laws gun.
They lined up properly on the rail and scope.

 

[Rich Coyle]

I lapp top and bottom of Talley rings.
I have been using Talley light weights for years without a problem.

Recently I bought a Pierce titanium action, Trigger tech trigger, Proof carbon barrel, Mbam titanium brake, March 2 1/2-25X52, a totally custom stock, and topped all this off with Talley light weight rings. I can afford the others but but don't see a need.