Aperture sight difficuties

[nztimb]

Am away for a hunt tomorrow so can not do anything about it now even if I could figure out the fix for my 6.5x57 SR Erfurts aperture sight problem. Up untill now I have been using the 2-7 scope on the Tally bases but I would like to be able to use both sighting systems depending on intended hunting destination/terrain etc.
I checked the zero with the scope and it was bang on after installing the scope on a cold clean barrel but when I put the aperture signt on and moved in closer for the first shot at a lasered 36 yds, the shots were 4 in high.
With a sight radius of 27 1/2 inches that is 27.5x4 divided by 1296 for .0849 of sight adjustment to have the shots print on at 100yds.
I already have a front sight that is .320 high off the ramp so dont want to have to go to an ungainly and probably bendy .41 front sight and there dosent seem to be any way to make a lower aperture slide for the talley

 

[ChrisG]

Am away for a hunt tomorrow so can not do anything about it now even if I could figure out the fix for my 6.5x57 SR Erfurts aperture sight problem. Up untill now I have been using the 2-7 scope on the Tally bases but I would like to be able to use both sighting systems depending on intended hunting destination/terrain etc.
I checked the zero with the scope and it was bang on after installing the scope on a cold clean barrel but when I put the aperture signt on and moved in closer for the first shot at a lasered 36 yds, the shots were 4 in high.
With a sight radius of 27 1/2 inches that is 27.5x4 divided by 1296 for .0849 of sight adjustment to have the shots print on at 100yds.
I already have a front sight that is .320 high off the ramp so dont want to have to go to an ungainly and probably bendy .41 front sight and there dosent seem to be any way to make a lower aperture slide for the talley

Hi VonGruff,

Have you considered the original British style of aperture sight that was dovetailed into the hammer? It seems like that wouldn't be too hard a modification. The sights themselves might be expensive... I don't know. I have only ever seen them on old Rigbys and a Doleac & Dorleac reproduction that was made a while back. i would think with a little bit od measuring and marking with a caliper, you could even cut the dovetail yourself with a dovetail file. Here's a pic of the sight I am talking about:

It even folds down and out of the way like some of the old lyman tang sights did when you want to mount a scope or just keep it from being damaged.

 

[nztimb]

@ChrisG I had a rigby styled cocking piece sight on the DWM 7x57 I built so I do know how effectife they can be but it was a cost consideration on this build that caused me to make the decission to use the Talley aperture on the Talley base. The one solution that I have come up with is to have a taller front sight made but keep it in the pouch with the aperture sight with a low front sight installed just for a complete front sight visual and when I want to change from the scope to the open sights it is no drama to change the front sight at the same time as the aperture sight is installed

 

[crs]

Is there an aperture sight in your first picture? If so, can you post a close up?

Does your Talley aperture look like this one on my .405 DR?

 

[nztimb]

Is there an aperture sight in your first picture? If so, can you post a close up?

Does your Talley aperture look like this one on my .405 DR?

View attachment 433415

Yes mine is mounted in the pic shown in the OP and it is the same as the one you have shown wityh windage but no elevation adjustment

 

[crs]

OK, thanks Von Gruff.
Here in this picture of the rear rib of my .405 DR, you can see the two sets of indentions where the two Talley scope rings attach.

When the scope is on, the Talley peep cannot be attached and vice versa.

Next, see the fixed rear leaf of the Express sight . Both the Talley peep and the scope sight through the V of this rear leaf - just as you would if aiming with only the the express sight. This way, the top of the stock can be made to be just right for aiming with the express sight and the stock will also be just right for aiming with the scope and for aiming with the Talley peep sight. I wish that I could take credit for this sight alignment feature, but credit goes to the clever gunmaker. He also implemented a right hand palm swell which, because of the two triggers, took a few shots to become familiar with.

 

[Bullthrower338]

Front sight is where I would go first!

 

[nztimb]

OK, thanks Von Gruff.
Here in this picture of the rear rib of my .405 DR, you can see the two sets of indentions where the two Talley scope rings attach.
View attachment 433427
When the scope is on, the Talley peep cannot be attached and vice versa.

Next, see the fixed rear leaf of the Express sight . Both the Talley peep and the scope sight through the V of this rear leaf - just as you would if aiming with only the the express sight. This way, the top of the stock can be made to be just right for aiming with the express sight and the stock will also be just right for aiming with the scope and for aiming with the Talley peep sight. I wish that I could take credit for this sight alignment feature, but credit goes to the clever gunmaker. He also implemented a right hand palm swell which, because of the two triggers, took a few shots to become familiar with.

My set up does not allow for that solution. The Talley bases are suited to the small ring action so no adjustment there as they are just right for the scope and heads up shooting and with the aperture in place are perfect allignment for the aperture sight so it si either the blade needs to be taller which I dont want to do or I may have to make a new rear and lower the aperture as far as is practical.

 

[nztimb]

Front sight is where I would go first!

That was where I went first Cody, but with calculations showing the need for a .41 high blade which is too tall to be sturdy so I am thinking that the best way is to get the top of the aperture base milled down and a new dovetail cut for the slide and that will take it down far enough to almost make the front sight usable at its present height or at least with very little extra height

 

[John P.]

I have solved a similar problem by machining a new aperture with offset hole.

 

[nztimb]

I have solved a similar problem by machining a new aperture with offset hole.

I had thought to mill off the dovetail slot in the base and cut a new one which will lower it enough to not have to raise the front sight. In the last couple of years the scope has not let me down so I have sort of put it on hold but "when" I get some time to play then that is where I will look to sort this.