scope shimming old school

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03 May 2022, 17:49

john c.

scope shimming old school

i've got a ruger #1 30-06 with a scope that has the 50mm front end so had to go with high bases. shot it yesterday for first time after installation. with elevation knob at lowest setting it hits approx 15" high at 125 yds with a 150 gr sp. years ago i would have cut up a coors can and shimmed the back bottom of the rear ring, and done the same to any gaps caused in the front ring. but times change and am looking for any better way from the actual experts to get this cat skinned. thanks

03 May 2022, 18:17

Jim Kobe

Cardinal rule: always shim the rear base/mount in the direction you want the bullet to go. Sounds like you are going the wrong way with a shim.

03 May 2022, 19:35

dian1

You've probably already addressed this but ring sets for #1's are the same height while ring heights for 77's are two different heights.
Maybe wrong set of rings???

03 May 2022, 20:30

Duane Wiebe (CG&R)

This brings back memories. I was in an auto parts store . Two guys were arguing about sight adjustments...drawing diagrams, etc...got a little heated!!

I whipped out a business card and tastefully explained that many folks have been through this same issue, so;...gunsmiths came up with a simple rule :

Always move the rear sight in the direction you want the bullet to go. I didn't even mention that the front sight was just the opposite because these guys were already close to a rucking fage..

03 May 2022, 21:01

impala#03

I have had good results with the Burris XTR Signature rings. The have Pos-Align Offset Inserts that have a lot of adjustments.

03 May 2022, 22:37

john c.

quote:
Originally posted by Jim Kobe:
Cardinal rule: always shim the rear base/mount in the direction you want the bullet to go. Sounds like you are going the wrong way with a shim.

yes but i am talking about the rings not the base. so if i want the POI to be lower i want the front of the scope to be lower and the rear to be higher so the shim would go between the bottom of the scope rear and ring. or under the rear base. scope needs to be rear higher and front lower. que no?

03 May 2022, 23:01

delloro

quote:
Originally posted by john c.:
quote:
Originally posted by Jim Kobe:
Cardinal rule: always shim the rear base/mount in the direction you want the bullet to go. Sounds like you are going the wrong way with a shim.

yes but i am talking about the rings not the base. so if i want the POI to be lower i want the front of the scope to be lower and the rear to be higher so the shim would go between the bottom of the scope rear and ring. or under the rear base. scope needs to be rear higher and front lower. que no?

I think you have it backwards.

03 May 2022, 23:19

dpcd

Yes. Of course with the scope reticle at the lowest setting your bullets will hit very high. Whilst the rule for rear SIGHTS is to move the sight the direction you want the bullet to go, scopes do not follow that rule.
It's easy to visualize.

04 May 2022, 03:09

Duane Wiebe (CG&R)

The OP might consider taking or sending the package to a qualified gunsmith. . He will (or should) set the internal adjustments at midpoint, then modify whatever is necessary so it at least boresights dead on. You'll then have plenty of internal adjustment

04 May 2022, 03:54

john c.

after hunting season this year i either put on new or switched around scopes on 3 rifles. i always use the Bushnell Professional Boresighter with the 3 diff (according to caliber) arbors. two needed very little adjustment at the range. this one is trying my patience. however, after todays responses, the light suddenly switched on in my haid. thanks

04 May 2022, 04:36

Bobster

Our shop has experienced several Ruger rings that had the half-moon recoil tabs oversized. This caused them to ride up when tightened and changed scope settings a great deal.

04 May 2022, 04:51

Hipshoot

Move rear sight in the direction that you want the bullet to go (this also means rear rings or bases).

Move front sight to chase the bullet, meaning move the front sight or front base or ring towards the bullet Point of impact.

Hip

04 May 2022, 15:50

p dog shooter

quote:
Originally posted by dian1:
You've probably already addressed this but ring sets for #1's are the same height while ring heights for 77's are two different heights.
Maybe wrong set of rings???

Happened to me with my first number one.

04 May 2022, 18:22

john c.

quote:
Originally posted by p dog shooter:
quote:
Originally posted by dian1:
You've probably already addressed this but ring sets for #1's are the same height while ring heights for 77's are two different heights.
Maybe wrong set of rings???

Happened to me with my first number one.

04 May 2022, 18:22

john c.

quote:
Originally posted by john c.:
quote:
Originally posted by p dog shooter:
quote:
Originally posted by dian1:
You've probably already addressed this but ring sets for #1's are the same height while ring heights for 77's are two different heights.
Maybe wrong set of rings???

Happened to me with my first number one.

damn i'll have to check that

04 May 2022, 18:23

john c.

quote:
Originally posted by Bobster:
Our shop has experienced several Ruger rings that had the half-moon recoil tabs oversized. This caused them to ride up when tightened and changed scope settings a great deal.

that too!

09 May 2022, 09:51

bghntr416

I read recently about another person who had the same problem. Sent the rifle back to Ruger. The quarter rib was out of spec and ruger replaced it if I recall correctly. If you don't want to send the gun back and the rings are correct look into the Burris Signature rings with the inserts that can be replaced as was mentioned earlier.

11 May 2022, 04:49

Atkinson

Clear me up on this, the Ruger #1 has screw attached quarter rib for a scope base, correct?? I suppose one could shim it but it would look tacky??? You cannot shim a Ruger ring as it has a button that goes in a slot..

Sounds like to me Ruger should give you a new barrel as it was installed cattywhumpus or is just bored less than true..or you have the wrong rings, your rings on a ruger #1 should be thesame...

13 May 2022, 00:44

john c.

i took the scope out of the leupold rings to shim it and noticed the front of the scope came out of the front ring bottom as if it was catching. in and out, it WAS catching a bit. i used to have many moons ago the steel rod with the handle on it that was used with grit to smooth and align rings. no telling where it is. i broke down and bought a set of warne rings, medium instead of high. got it mounted with no catch etc and with a hairs breath plus 2 to clear the bell of the scope from the base front. now shoots on target as is supposed to with plenty of adjustments both ways. did not shoot for accuracy this time, used "siter" rds, just to see where the rds would hit on the gongs and paper. much much better and as it should be.

10 June 2022, 13:16

sambarman338

Hopefully a hair's breadth clearance at the objective is enough. Recoil inertia could see a big, long bell flex down, cf a car body under braking. If it then contacts the barrel, strange outcomes may result

10 June 2022, 23:32

458Win

quote:
Originally posted by Duane Wiebe (CG&R):
This brings back memories. I was in an auto parts store . Two guys were arguing about sight adjustments...drawing diagrams, etc...got a little heated!!

I whipped out a business card and tastefully explained that many folks have been through this same issue, so;...gunsmiths came up with a simple rule :

Always move the rear sight in the direction you want the bullet to go. I didn't even mention that the front sight was just the opposite because these guys were already close to a rucking fage..

Duane, I had that happen to me in AIT ("Advanced"? Infantry Training) when an instructor was trying to explain how to adjust the sights on the M16. He didn't understand the difference between adjusting the rear sight and the front

Anyone who claims the 30-06 is ineffective has either not tried one, or is unwittingly commenting on their own marksmanship
Phil Shoemaker
Alaska Master guide
FAA Master pilot
NRA Benefactor www.grizzlyskinsofalaska.com

11 June 2022, 04:45

Hipshoot

The simplest terms that I have come across in my 68 years of shooting are;

Move the rear sight in the direction that you want the bullet to go!

AND (from archery)

Front sight-----Chase the Arrow (Your pin is the front sight)

Hip

11 June 2022, 21:39

Atkinson

Bottom line is I would almost bet a black land farm against an old set of shoes, you got the wrong rings..I believe you stated you had to purchase the high rings, Its a 77 therefore the rear ring is the highest of the two, on a no.1 the rings are the same height...and of course both rings need to bottom out..

Iron sight solution is as described in earlier posts here..You should never need to shim a Ruger or any rifle with integral bases..