HK91/G3 sight adjustment?

[Monkeyleg]

I had thought, based on posts I'd read here, that the different aperatures on the HK91/G3 sights were for adjusting elevation.

But, no matter which aperature I use, my G3 is still shooting high. About five to six inches high at 50 yards. I have to aim at the very bottom of the target to get the shots anywhere near the black in the middle. Windage is fine.

I've also seen HK91 sight adjustment tools on Gunbroker.com, but $26 plus shipping seems pricey for a handle and two pins. Is there a practical but less expensive alternative?

This is the Century G3 that I've been asking/complaining/screaming about for months. Century fixed an internal problem, I fixed another internal problem, then bought some very used HK91 furniture and painted it.

It's nowhere near as accurate as any of my other rifles, but it's definitely fun to shoot. And now it functions 100%. If there's ever any riots or other social problems in the city, I can hand the rifle over to a neighbor who needs it and not worry about it going "click" instead of "bang."

 

[Swamp Yankee]

Hemostats work just fine.

Iadjusted the sights on my PTR91 with a set of straight hemostats. Needle nose pliers worked, but the hemostats worked much better.
Take Care

 

[Monkeyleg]

Thanks, Swamp Yankee. I'll rush right out and buy a hemostat.

First, though: what the heck is a hemostat?

 

[greg531mi]

First, though: what the heck is a hemostat?

It's one of those stainless steel locking pliers dealys that you get the fish hook out in fishing.

It is mainly used for in surgery, to compress arteries from losing too much blood, but are great tools like fly tieing and such.....

 

[Monkeyleg]

Ok, went to a science surplus store and got a hemostat for $3.25.

I hate to sound dumb, but what am I doing with it? When I compress the two holes, the sight drum turns, but I don't know if I'm actually moving the height of the drum at all.

From what I've read, it sounds like the three aperatures are for different distances, but I haven't seen any change in the point of impact using any of them.

Any replies much appreciated.

 

[Father Knows Best]

Here's a great webpage on the HK sights and how to adjust them: http://www.hkpro.com/sights.htm

 

[Monkeyleg]

Thanks for the link, Father Knows Best.

I was over on the cetmerifles.com forum, and found a post from someone who was having the same problem I have. He suspected that there was rust on the threads of the sight drum, and used some penetrating oil.

Once he had the sight drum freed up, he unscrewed it until the threads were visible, and took a photo. Very clear to me now how the sight drum is constructed.

I suspect mine is rusted on as well. I'll try the penetrating oil trick and see if it works.

If not, I'll make new targets, with one bullseye at the bottom, and another about 5 1/2" above, and just aim for the bottom bullseye.

 

[Dave R]

There may be a setscrew you need to loosen before you can turn the sight post. Check the font (muzzle) side of the front sight post. If there's a screw visible there, you'll have to loosen it before you can get the sight post to turn. Then, when the sight is properly adjusted, tighten it up again and the post won't move.

If your G3 is like a CETME, it'll have that setscrew.

 

[Monkeyleg]

Thanks, Dave. There's no setscrew on the front sightpost. It's fixed. The only way to change elevation would be to file the front sightpost.

For all of those kindly responding to my questions, remember that this is a Century Arms G3. Meaning that many parts are older than most THR members. I have no doubt that the sight drum could be rusted onto the threads.

Right now the whole sight assembly is soaking in oil. Hopefully, by tomorrow, the drum will turn independent of the spring-loaded tensioners.

I bought/traded this rifle for a couple of reasons. One was that I thought it would be a challenge to make it 100% reliable. And that has been a challenge, but it's there. Also, it's just fun to plink with.

Another reason was that I figured if Milwaukee got into a New Orleans situation, one of my neighbors might need a good rifle. There's no way I'll lend anybody my AR, my Benelli M1S90, my Remington 700 Police, or even any of my pistols.

I got to talking to a good neighbor of mine today about New Orleans, and mentioned the G3. He questioned why he'd ever need one. I reminded him that he had two young and attractive daughters, an attractive wife, a great house, four cars, and just about anything else a scumbag would want.

I said, "Mark, when I'm done with this rifle, it's yours if you need it. I'll give you plenty of magazines, and a few hundred rounds. It's a point-and-shoot rifle, and will put down any scumbag who's threatening your family."

He's done umpteen favors for me. If the time comes, and I hope it doesn't, this will be my favor to him.

 

[Onmilo]

If you zero the rifle at 100 meters and then turn the sight drum to the 300 meter setting you will find the rifle will print point of impact to point of aim at 25-50 meters.

You will not be able to dial the 100 meter apeture or V notch to a 50 meter setting, there isn't enough screw adjustment in this type of sight to be able to do that. HTH

 

[Monkeyleg]

Onmilo, thanks for the reply. Now I'm even more confused than ever.

Please tell me where I'm wrong in what I've read: the V-sight position and the #1 aperature setting are for a point-of-impact sight picture at 100 metres. Am I wrong on this?

My understanding was that each consecutively smaller aperature--#2, #3, and #4---were for distances further than 100 meters.

Any further clarification you can provide would be much appreciated.

 

[Feanaro]

You are correct. The V-notch is intended for use at 100 meters, the first aperture(2) for 200, etc. However, I've never heard of any G3/HK91 owner using the V-notch often. Even the Bundeswehr discourages the use of the first sight except for quick close range shots, IIRC. Usual practice is to zero the first aperture sight at the standard 200 meters but use it for 100 as well.

 

[Father Knows Best]

Monkeyleg, Onmilo is right. It is common to set the sights on battle rifles such that they have two "zero" ranges. That's because the bullet will pass through the line of sight twice: once on the upslope of its trajectory, and once again on the downslope, like this:

 

[Monkeyleg]

Thanks, all, for the clarification. That makes sense.

Letting the sight sit in oil overnight did the trick. Now, if I can get someone to go to the range with me tomorrow, I can get this thing zeroed (our range now requires two people to be present before anyone can shoot).

 

[Monkeyleg]

Just another thank-you for the explanations.

It was hot and humid at the range today, and sweat kept getting in my eyes as I struggled with the hemostat to adjust the drum.

Considering that this is a combat rifle with combat sights, and that I was using Portugese milsurp ammo, I thought it shot pretty well. It took ten rounds to get finally get it into the black, but after that it was consistent.

If any of my neighbors need a HD rifle, this should suffice.