Scope Leveling

[Orka Akinse]

Fellows

 

My next job is to mate Third Eye rings to my new 5-25 S&B and I got to thinking; If I was to sit the rings on a flat surface and then mount the scope using engineering leveling tools to the rings is it just a case of securing the lot to the picatinney rail or am I missing something?

 

 

[jcampbellsmith]

http://bulletin.accurateshooter.com/2009/02/canted-reticles-serious-problem-needs-to-be-addressed/ Can you guarantee the optics are 100% aligned with the mechanical parts? Regards JCS

[Orka Akinse]

http://bulletin.accurateshooter.com/2009/02/canted-reticles-serious-problem-needs-to-be-addressed/ Can you guarantee the optics are 100% aligned with the mechanical parts? Regards JCS

 

Take your point but can you ever guarantee 100%? I'm not hard over its just a thought I had that as the correct tools will be used and all the mating parts are engineered to tight tolerances it would work?

[terryh]

Ian,

 

Once you've put it together as well as you think then you need to go shoot the rifle and test the set up.

 

Get a piece of paper about 30+ inches tall (wall paper's pretty good). Set up this blank piece of paper at say 100 yards and with a spirit level put a verticle line on the paper then, with the spirit level put a horizontal line at the bottom of the verticle line so you end up with an inverted 'T'. Put a seperate dot off to one side.

 

Sight in on the dot. Then aim at the joint in the T, then wind on some elevation and aim at the same point, the junction of the 'T', wind on some more elevation, aim at the same point etc. then come back down using the same elevation increments. As you've a 'metric' PM2 use 2mil increments which at 100 will give about 7" steps in bullet movement on the target.

 

If your scope's lined up with the rifle the bullet holes should go up and down the verticle line, if its not the bullet holes and verticle line will diverge.

 

Hope that makes sense?

 

Terry

[MJR]

Ian,

Your method assumes the rail is square to the action. I like to clamp the rifle so its vertical then align the reticle with a plumb bob or know vertical object such as a door jamb. Then follow Terry's advice and prove it In the field. If its a new scope you can box test it at the same time.

[Orka Akinse]

Awesome Terry thanks, will do

[Orka Akinse]

Ian, Your method assumes the rail is square to the action. I like to clamp the rifle so its vertical then align the reticle with a plumb bob or know vertical object such as a door jamb. Then follow Terry's advice and prove it In the field. If its a new scope you can box test it at the same time.

Hi Mike the action was machined square and then drilled and tapped (Sako 75 MkIV) no holes for a rail in the action, before the rail was fitted so pretty confident its square. The S&B has a flat surface at the base of the turret housing so assuming the rings are within tolerance and I use a level gauge and fit the rings to the scope and then fit the lot to the rifle's action I think I would be pretty much there or there abouts.

 

Of course Terry's test will confirm if everything is as true as I think it is.... I will shoot it and let you know

[Orka Akinse]

Terry

 

Just one question, if a cant is visible, how is it measured so I know how much to turn the scope? Is there a procedure or is it just lining it up using the target?

[brown dog]

One thing I wouldn't do, is muddle this with shooting.

 

Whether the scope tracks vertically is a visual thing, not a shooting thing - you want to test the scope, not your ability to shoot.

 

With the 5-25 PM2 you can also check tracking at the same time....and do it all at 10metres in the scullery (should the main kitchen be busy) or your garden.

 

Clamp the rifle. Hang a cm ruler at 10m. Point the cross hair at the edge of the ruler (either by moving the rifle, or by moving the ruler to where the rifle's pointing.)

 

Then wind elevation on.

Does it go up the vertical ruler's edge?

Do 30 clicks / 150 clicks (etc) move the cross hair EXACTLY 3 cm / 15cm (etc) up the ruler (each click will be 1mm at 10m). Does it then wind back to where it started?

 

 

I found with PM2s that you can get perfect perpendicularity by visually (from both sides of the rifle) setting the base of the saddle parallel with the flat surface of the rail (didn't you buy some parallel gauges from Davy help with that?).

[Orka Akinse]

A picture paints a thousand words...

 

Now the summers coming I will bring it all round to your scullery and we can do it together bud, I will come bearing gifts......

 

I did buy some parallel gauges bud yes...

[dannywayoflife]

Personally I now use davy's levels and then just check it with a spirit level on the action and a plumb line at about 12 yds. Since I've been using Davy's levels I've not had to alter it when checking with the plumb line.