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Tight focus knob on sightron SIII6-24xLRMD

31 May 2017
@ 02:25 pm (GMT)

Murray Dixon

Hi everyone. I am having trouble with the side focus knob on my scope as it is getting tighter to adjust. Being in a ute in WA I am guessing fine dust being a problem. Can I loosen and remove cover to clean?


18 Jun 2017
@ 04:48 am (GMT)

Bryan Webster

Re: Tight focus knob on sightron SIII6-24xLRMD
Sightron will provide the info you need:

Address: 100 Jeffrey Way, Suite A, Youngsville, NC 27596
Phone: (919) 562-3000
Fax: (919) 562-7129
Email: [email protected]
18 Jun 2017
@ 10:42 am (GMT)

Nathan Foster

Re: Tight focus knob on sightron SIII6-24xLRMD

Hi Murray, gosh its been a long time. I trust all is well with you and your family.

Regarding the parallax knob, it sounds almost like the tube has been bent or the front scope ring is crushing via immense force, misalignment and or sharp lead edges. This will arrest the parallax (feels gritty like dust but is actually internal) but generally only effects a 1" tube optic. It would take some force to effect the SIII tube.

Take the scope off and check for crushing, check to see if the parallax now works smoothly away from the rifle and rings. If it does, change the mount set up (and or lap), then try again. You may find that after such damage has been done, you can no longer use the old ring position regardless of lapping. The front ring may have to be shifted further forwards.

Otherwise, contact Sightron as Bryan has suggested. Diagnosing such problems via a forum can be disastrous.
18 Jun 2017
@ 02:48 pm (GMT)

Murray Dixon

Re: Tight focus knob on sightron SIII6-24xLRMD
Hi Nathan and Bryan

Thanks for the advice.
I feel the adjustment knob is just tight not damaged but I will certainly try and see if crushing is the problem.

Family all well thanks Nathan.Best wishes to you and yours.


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