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DGR375
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Reged: 04/10/07
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Loc: Gold Coast, QLD

what height new foresight for Merkel?
#139647 - 27/07/09 03:49 PM

Collected my new Merkel DR in 9.3x74R last week. On first tryout, I found it shooting about 8 inches high at 50 metres. Thus, a new foresight is needed.

The current foresight is this:

and

This foresight is 4.25mm high from the base.

Questions:
Which brand and model to get?
How high should it be?

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500Nitro
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Re: what height new foresight for Merkel? [Re: DGR375]
#139648 - 27/07/09 03:53 PM

You have to use a formula to work it out - which I don't currently have at hand.

Are you using factory ammo or reloads ?

If reloads, have you tried adjusting your loads to raise the POI on the target ?

Also, how are you sighting the gun (rear sight / front sight) ?

What does the factory target show - Does it show the POI at the POA ?

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Fritz
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Reged: 13/04/03
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Re: what height new foresight for Merkel? [Re: 500Nitro]
#139652 - 27/07/09 04:29 PM

8 inches make 20 cm. If we suppose that the distance between bead and rear sight is 50 cm, you ought to get a 2 mm higher bead. However, such a high bead is easy to break, and personally I'd prefer to lower the rear sight if possible.

But first of all you should try the same load, as the gun was regulated with. High hits may indicate that the rifle is sighted in with heavier bullets - 286 grs are standard. Information about that should be written in the test protocol from the factory. If you don't have got the protocol, you should send the factory an e-mail about the issue.

I had the same problem with my stone age 8x57IR drilling, which once was sighted in with 220 grs bullets. As only 196 grs are available today, my fresh loads hit about 6" high @ 100 metres. A new 0.75 mm higher bead solved my problem.

Fritz

P.S. Recknagel has fine sights http://www.magnumhansen.com/Recknagel_Katalog_5.pdf

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DGR375
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Re: what height new foresight for Merkel? [Re: 500Nitro]
#139653 - 27/07/09 04:30 PM

No factory target was provided. I was using RWS 291gr EVO factory ammo ($A155 per 20). The bottom of the bead was resting on the bottom of the V of the rear sight. I'm leaving reloads for another day.

I did have a few GECO 255 gr factory loads, POI remained the same. So did a few odd reloads made for my old Ruger No1., I just tried these to empty the cases and practice trigger release.

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Fritz
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Re: what height new foresight for Merkel? [Re: DGR375]
#139654 - 27/07/09 04:42 PM

Quote:

No factory target was provided. I was using RWS 291gr EVO factory ammo ($A155 per 20). The bottom of the bead was resting on the bottom of the V of the rear sight. I'm leaving reloads for another day.

I did have a few GECO 255 gr factory loads, POI remained the same. So did a few odd reloads made for my old Ruger No1., I just tried these to empty the cases and practice trigger release.

Strange - the POI should not be that high with correct bullet weight.

How do you rest your rifle when testing it? Doubles and drillings are finicky with such things, and testing from the bench can give misleading results. Does it hit too high when your shoot off-hand?

Fritz

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500Nitro
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Re: what height new foresight for Merkel? [Re: DGR375]
#139655 - 27/07/09 04:43 PM

For a start, try having the bead LEVEL with the rear sight instead of in the bottom of the V.

Shoot a few rounds and see if this makes a difference.

I'd also try the other RWS Ammo, not the EVO and see if that makes a difference.

IMHO, the LAST thing you want to do is fuck around with the sight before you have tried all the other options.

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450_366
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Re: what height new foresight for Merkel? [Re: DGR375]
#139658 - 27/07/09 06:25 PM

Do you aim at the top of the bead or behind it`?

--------------------
Andreas

"Yeas it kicks like a mule he said, but always remember that its much worse standing on the other end"

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Tatume
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Re: what height new foresight for Merkel? [Re: 450_366]
#139662 - 27/07/09 09:19 PM

This is a problem of similar triangles. The sight radius (r) and range (R) are congruent legs, and the front sight height change (h) and impact change (H) are congruent legs. All measurements must be in the same units. Therefore:

h/r = H/R or equivalently h = (Hr)/R

Example: sight radius 20 inches, range 1800 inches (50 yards), impact change 8 inches.
h = 8(20)/1800 = 0.089 inches.

--------------------
Take care, Tom
NRA Life Member

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DGR375
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Re: what height new foresight for Merkel? [Re: Tatume]
#139665 - 27/07/09 10:41 PM

All aiming is at the top of the bead. All shooting was done offhand.
I hadn't mentioned that Merkel had supplied the wrong sights (it came with one of those horrible plastic front sights and weird rear sight that is popular in Germany), and so the distributor in Australia got Merkel to send over the express sights that I had wanted. These were installed by a Melbourne gunsmith; I presume they weren't test fired before the rifle was sent back to me. I have no desire to send it back for another 3-6 months, and so was hoping for a local fix.

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DUGABOY1
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Re: what height new foresight for Merkel? [Re: DGR375]
#139670 - 28/07/09 12:48 AM

Quote:

All aiming is at the top of the bead. All shooting was done offhand.
I hadn't mentioned that Merkel had supplied the wrong sights (it came with one of those horrible plastic front sights and weird rear sight that is popular in Germany), and so the distributor in Australia got Merkel to send over the express sights that I had wanted. These were installed by a Melbourne gunsmith; I presume they weren't test fired before the rifle was sent back to me. I have no desire to send it back for another 3-6 months, and so was hoping for a local fix.

On all the Merkel double rifles I own, or have owned, the sight picture was with top of the front bead level with the top of the rear sight,like a handgun sight, with the bull's eye sitting on top of the front bead,at the range engraved on the rear sight.
.................................Example................ [\0/]

If you are placeing your bead deep in the bottom of the rear sight,that is not the way Merkel sights are used. I think placeing the bead level with the top of the rear sight may just put you on target at 100 yds. All Merkel 9.3X74R doubles have their sights regulated ( CUT )for dead on at 100 yards, with this sight picture.

.........................Hope this helps!

--------------------
..........Mac >>>===(x)===>
DUGABOY1, and MacD37 founding member of DRSS www.doublerifleshooterssociety.com
"If I die today, I have had a life well spent, for I've been to see the Elephant, and smelled the smoke of Africa!"

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ALAN_MCKENZIE
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Re: what height new foresight for Merkel? [Re: DUGABOY1]
#139671 - 28/07/09 01:15 AM

Brownells have a diagram and formular in their # 61 catalog on page 214.
I have no way of scanning it at the moment so one of our members might be able to help.

Al

--------------------
"Dogs always bark at their master"
Sir Seretse Khama.25th June 1949

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Tatume
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Re: what height new foresight for Merkel? [Re: ALAN_MCKENZIE]
#139676 - 28/07/09 01:54 AM

The instructions on pg 214 of the Brownells catalog explain how to set both front and rear sights the same distance above the centerline of the bore. In fact, the rear sight must be considerably higher above the bore centerline than the front sight. Brownells is depending on the assumption that the elevation adjustment of the rear sight will be sufficient to make up the difference. Clearly this is not the case with Mr. DGR375's Merkel.

--------------------
Take care, Tom
NRA Life Member

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500Nitro
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Re: what height new foresight for Merkel? [Re: Tatume]
#139677 - 28/07/09 02:34 AM

But how does that work on older guns - or new guns for that matter - where the rear sight is made, blued and been fitted.

Apart from filing the rear sight (my least preferred option),
I was always under the view that you change the front sight
if you can't change the POI any other way.

I also agree that having too high a front sight is not good for potential damage reasons and IMHO, it doesn't look right.

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400NitroExpress
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Reged: 26/11/03
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Re: what height new foresight for Merkel? [Re: DGR375]
#139679 - 28/07/09 04:06 AM

Quote:

All aiming is at the top of the bead. All shooting was done offhand.
I hadn't mentioned that Merkel had supplied the wrong sights (it came with one of those horrible plastic front sights and weird rear sight that is popular in Germany), and so the distributor in Australia got Merkel to send over the express sights that I had wanted. These were installed by a Melbourne gunsmith; I presume they weren't test fired before the rifle was sent back to me.

I think that's the answer. I agree with you about the sights that come standard on the Merkel, BTW. New express sights (front bead and wide rear V) aren't just "slap on 'n go". They're not made that way. When properly made express sights are first installed, ELEVATION WILL BE HIGH - it's SUPPOSED to be. The height of the rear V is made high on purpose, so that correct elevation can be properly filed in. When new express sights are properly installed on a double rifle by a gunsmith that knows what he's doing, he first fires it with the load it was regulated with. Elevation will be high. He then files the rear V, shoots again, files some more, etc., until elevation is properly filed in with the sight picture specified by the customer. Doesn't sound like the required questions concerning load and sight picture were even asked, let alone any shooting or adjustments done.

Yes, replacing the front sight with a taller one will have the same effect, but that is not the correct procedure with new express sights.

From the photos, your front bead is already quite tall enough to be easily damaged. Were it mine, I'd prefer to shorten it rather than raise it. Also, I'd get it to a qualified smith to have the front ramp milled for a Brownell's hood to protect the front bead (another complaint I have about Merkel and others). If you're comfortable with that height, fine. The high elevation issue is the rear V, not the front sight. That's true by definition - because they're NEW express sights.

Bottom line, your replacement sights were not properly installed. If the "gunsmith" didn't even shoot it, let alone file the rear V in, then your sights are doing exactly what they should be doing. I think it needs to go to a different smith that's qualified for the job.

--------------------
"Serious rifles have two barrels, everything else just burns gunpowder."

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Tatume
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Re: what height new foresight for Merkel? [Re: 400NitroExpress]
#139680 - 28/07/09 04:16 AM

Quote:

When properly made express sights are first installed, ELEVATION WILL BE HIGH - it's SUPPOSED to be. The height of the rear V is made high on purpose, so that correct elevation can be properly filed in. When new express sights are properly installed on a double rifle by a gunsmith that knows what he's doing, he first fires it with the load it was regulated with. Elevation will be high. He then files the rear V, shoots again, files some more, etc., until elevation is properly filed in with the sight picture specified by the customer.

Quote:

This is a problem of similar triangles. The sight radius (r) and range (R) are congruent legs, and the front sight height change (h) and impact change (H) are congruent legs. All measurements must be in the same units. Therefore:

h/r = H/R or equivalently h = (Hr)/R

Example: sight radius 20 inches, range 1800 inches (50 yards), impact change 8 inches.
h = 8(20)/1800 = 0.089 inches.

Note that this method will just as easily give the amount by which the rear sight should be changed. Do the calculation, and on the first filing, do not take off more than the calculated amount.

--------------------
Take care, Tom
NRA Life Member

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4seventy
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Re: what height new foresight for Merkel? [Re: DGR375]
#139685 - 28/07/09 07:55 AM

DGR375,
Some have suggested that you should be holding your bead level with the top of the rear vee. This will actually worsen your problem and make the point of impact even higher on the target than it is now!
As 400NE has suggested, your rear sight needs to be filed to give the correct POI on the target.
Filing a rear sight may sound like a simple job, but it isn't easy to keep all the angles correct, central, and symmetrical.

Are you certain that you are holding the bead right at the very bottom of the vee?

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400NitroExpress
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Re: what height new foresight for Merkel? [Re: 4seventy]
#139688 - 28/07/09 08:34 AM

Quote:

Note that this method will just as easily give the amount by which the rear sight should be changed. Do the calculation, and on the first filing, do not take off more than the calculated amount.

Of course, a qualified smith will know that, and won't take off as much as the calculated amount before shooting and fine tuning.

Quote:

Filing a rear sight may sound like a simple job, but it isn't easy to keep all the angles correct, central, and symmetrical.

Fully agree. Also, the flats of the V must be filed so that they're angled away from the shooter's eye (they should be beveled sorta like a knife edge), otherwise glare off the flats will cause the front bead to fuzz out. Sincerely, I think it needs to be done by someone familiar with it.

--------------------
"Serious rifles have two barrels, everything else just burns gunpowder."

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DGR375
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Re: what height new foresight for Merkel? [Re: 400NitroExpress]
#139690 - 28/07/09 10:36 AM

Thanks, everyone. I'm consulting with Alex Beer in Tasmania. As he builds double rifles I am confident he is the man for the job.

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DGR375
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Re: what height new foresight for Merkel? [Re: DGR375]
#139692 - 28/07/09 12:39 PM

Alex has made the suggestion some of you have made i.e. to file down the rear sight. This I will do, gradually, testing along the way. I'll let you all know how it goes.

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REN3
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Re: what height new foresight for Merkel? [Re: DGR375]
#139709 - 29/07/09 12:30 AM

One thing that has been left out of this informative discussion is the "automatic" sight picture (alignment of the sights with the shooter's eye) as the gun is brought up in shooting position. Instead of filing the rear sight I installed a slightly higher (.040") front sight to align the sights with my eye so that I hve the best automatic alignment of the target and my eye. I am not shooting dangerous game, but to be able to close one's eyes and throw the double rifle up to my shoulder repeatedly, and then open my eyes with the target perfectly in my sights is real fun! Thanks.

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4seventy
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Re: what height new foresight for Merkel? [Re: REN3]
#139724 - 29/07/09 07:36 AM

Quote:

One thing that has been left out of this informative discussion is the "automatic" sight picture (alignment of the sights with the shooter's eye) as the gun is brought up in shooting position. Instead of filing the rear sight I installed a slightly higher (.040") front sight to align the sights with my eye so that I hve the best automatic alignment of the target and my eye. I am not shooting dangerous game, but to be able to close one's eyes and throw the double rifle up to my shoulder repeatedly, and then open my eyes with the target perfectly in my sights is real fun! Thanks.

Very true, and this is how I like the sights to be set up on my doubles as well!

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eagle27
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Re: what height new foresight for Merkel? [Re: 4seventy]
#139753 - 29/07/09 05:58 PM

DRG

Have been thinking about this issue of raising the front sight or filing the rear V to set the correct POI. Had to do it when I purchased my Mauser opened up to .404 Jeffery which had obviously not been resighted as the POI was about 8” high.
I achieved the correct POI and sight picture I wanted by making a higher blade (than necessary) for the foresight and filing down to achieve a dead on the bulls-eye POI at 50m with factory ammunition (two brands to same POI).

The sight picture is with the flat top of the blade (will add a bead one day) in the shallow V and level with the shoulders of the English safari rear sight. I don’t like a six o’clock hold but prefer a centre hold on target.

John “Pondoro” Taylor on sights and sighting did not like small beads down in a deep V rear sight and for DG use preferred a wide shallow V with a larger bead level with the shoulders. I suspect, like the automatic centering of a front sight in an aperture sight, our eyes would tend to also automatically place a bead or blade level with the rear sight shoulders.

If the POI had been set with the bead low in a deep V, while possible to consciously use this sight picture on targets, under stress on DG or even PG (a charge or hurried shot) I suggest (as Taylor does) a high shot will result when the bead is subconsciously raised level with the rear sight shoulders. On a closing head shot this could be a dangerous miss.

I do have much experience in using open sights, V and blade or bead, on other rifles and have always use the same sight picture. Also find apertures very good as well, but now use scopes exclusively, on the .404J as well.

Unfortunately the front sight on your Merkel is already quite high and as has been suggested, you need to file down the V. You don’t show the rear sight so not sure if it is a shallow or deep V already. I would file the V and the shoulders down to maintain a shallow V and achieve a sight picture with the bead level with the shoulders.

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DGR375
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Re: what height new foresight for Merkel? [Re: eagle27]
#139756 - 29/07/09 06:47 PM

Good thoughts, Eagle27. This is the rear sight:

I will definitely be keeping a shallow V. I'll start with the bead at the bottom of the V, as there is less metal to remove, but will keep in mind your thoughts about the sight picture you suggest, as this is the sight picture that I am used to, after many years of pistol shooting i.e. top of bead level with shoulders.

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DGR375
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Re: what height new foresight for Merkel? [Re: DGR375]
#139758 - 29/07/09 06:52 PM

Another thought: those Germans can't seem to get away from funny sights on double rifles; I'll have to do something about those narrow notches on the folding leaves. Either that, or just ignore them altogether, just leaving them folded down as decoration. European gunmakers don't seem to understand the concept of express sights.

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eagle27
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Re: what height new foresight for Merkel? [Re: DGR375]
#139766 - 29/07/09 09:34 PM

Apart from the folding leaves the standing rear sight is perfect, JT would love it, even though he didn't like any extra folding leaves. Seems to be plenty of metal there to allow you to file both the V and the shoulders. My own English style rear sight on the .404J also has all the extra leaves but I'm not about to remove these off an Oberndorf Sporter.
Yes I would certainly stick to the same sight picture that you have used for pistol shooting as this is probably what will come naturally to you now.

Good luck and let us know how you get on.

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