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Getting my scope to work on a 2240 with 18'' barrel

Started by Paul, June 02, 2016, 06:59:07 AM

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Paul

Hi Guys and Gals

I have fitted a Hawke Eclipse 4-16x50 AOIR Scope to my 2240.
Distance between Barrel and scope is about 1/4''.

Unfortunately I have run out of elevation adjustment and I'm about 8" low on target.
What is the easiest fix for this problem, thanks in advance.

mr007s


JMJinNC

A shim under the scope on the back ring will help.

I punch my data into Chairgun and size my shim to get the scope centered at my preferred zero. Once Chairgun data is in, all you will need is the scope ring spacing and a healthy understanding of trigonometry.

JMJ
John


JMJinNC

Assuming 4" ring spacing, you'd need a .032" (.82mm) thick shim just to get you back on target. I'd go more to get the scope centered.

JMJ
John

Paul

Quote from: JMJinNC on June 02, 2016, 02:28:11 PM
Assuming 4" ring spacing, you'd need a .032" (.82mm) thick shim just to get you back on target. I'd go more to get the scope centered.

JMJ
Thanks for the quick info my rings are 4 1/2'' front to back I will fit a slightly thicker shim in the morning, as it's getting late here now.

mr007s

I would return the scope to optical centered and begin from there. Once the scope is optical centered shoot a 3 or 5 shot group and measure how much the group is from there.
The last scope I mounted I used the Burris Zee Rings. They are a bit pricey but they will get you on target without extreme adjustments with turrets. Your view thru the scope will be clearer the closer you stay in the center.

JMJinNC

Agree with mr007s.

Your shim will need to be .0046" for every inch you are off center after you've optically zero'ed the scope.

JMJ
John

WyoMan

Good suggestions above  :-*
I would also make sure the breech is sitting flat on the tube...i.e. no gap between the two in the front.
Wyo
Welcome to your life :)
Member of the Western Heretic Alliance

RinCG

Quote from: mr007s on June 02, 2016, 04:32:40 PM
I would return the scope to optical centered and begin from there. Once the scope is optical centered shoot a 3 or 5 shot group and measure how much the group is from there.
The last scope I mounted I used the Burris Zee Rings. They are a bit pricey but they will get you on target without extreme adjustments with turrets. Your view thru the scope will be clearer the closer you stay in the center.
420554 matte medium
420556 matte high
Both are for 1" scopes, which I believe the Hawke Eclipse is Not.
If you can fit a airgun to Weaver adapter = 420558 matte medium
The Zee's run 50-60 dollars and they come with inserts "0" and +/- "10"- supposedly Burris feels there is enough adjustment in the 30mm turrets to compensate for more???
You could also carefully give the barrel an adjustment by giving it a bend in the correct place. Sounds much worse than it really is.
Best Luck 

Paul

Thanks for all the info folks, as I live in Thailand buying anything for an Air rifle is a nightmare and usually ends in a quick fix outside the box or a 2 week wait to import parts, (that may or may not be useful).
I have put an old tyre inner tube under the scope at the back and this has now moved the scope to the opposite scale.
I only just have enough down turns on the turret to get to zero level what ever you call it, so now I can tighten the scope mount more and raise the zero nearer to the scopes centerpoint and compress the inner tube tighter.