Spring Actuated BUIS - Back Up Iron Sight

[FighterAce]

I need some sort of back up iron sights for my new sniper rifle in case the scope breaks. I found some airsoft magpul ones but they are almost $80 so I figured if I could make them, I would invest less then $1 since I think I already have all the parts in my collection... springs, nuts, washers, etc. except for a piece of walnut witch I plan on using as the body.

If anyone doesnt know what I'm talking about... take a look at this



The only problem for me is the flip up/flip down and retaining part. Does anyone know how those sighs flip up by just pressing a button and lock in place once you push em back down? If not, could anyone suggest such a mechanism so it fits into the body of the BUIS in the image above? Since I'm making a sniper replica it would be nice to have replica sights too

[hi]

I think its just constantly under pressure from the spring and when you push the button it releases a sear and it flips up.

like a sear pin on a bolt action rifle.

[Insomniac]

Yep, looks like a pretty simple spring-loaded mechanism. Shouldn't be too hard to fabricate somthing similar.

[FighterAce]

I think its just constantly under pressure from the spring and when you push the button it releases a sear and it flips up.

like a sear pin on a bolt action rifle.

Could you draw a sketch or something? I'm not really familiar with such mechanisms

[Crna Legija]

i think a mousetrap type of thing would be best, but you would have to set it every time

[FighterAce]

That wouldnt be so great... I would need to lock it down manually as opposed to pushing it down and having it lock automatically.

btw. any special reason for having a Croatian flag in your avatar?

[Crna Legija]

im croatian

[Insomniac]

Not to sound condescending, but surely you can figure out how to do this. This type of mechanism is found everywhere. A few examples: Doors of microwave ovens, latches on guitar cases and briefcases, pop-up flashes on digital camera, hell even a jack-in-the-box uses a similar mechanism.

This ironsight obviously moves the latch from an external to an internal mechanism (which is a bit more difficult to design or build), so it is a bit different but it really isn't difficult to figure out how to construct somthing similar.

[FighterAce]

The examples you just said usually have a tab witch you move. Tab extends a piece of metal/plastic into a depression in the body and thus holding it shut. On this design all I have is a button... I dont see how you can apply the same mechanism to the sight.

Anyways.. I just thought of a spring loaded button retainer design as opposed to spring loading the whole moving part of the sight and a sear to hold it.

[Insomniac]

The examples you just said usually have a tab witch you move. Tab extends a piece of metal/plastic into a depression in the body and thus holding it shut. On this design all I have is a button... I dont see how you can apply the same mechanism to the sight.

Anyways.. I just thought of a spring loaded button retainer design as opposed to spring loading the whole moving part of the sight and a sear to hold it.

And that button is likely directly linked to such a tab, hidden within the mechanism. Said tab would be spring loaded so that the button always returns, and the tab would be cut at an angle so pushing the sight down would press the button inwards, allowing it to latch. I'd draw a diagram but it's late and my drawing skills are dismal at best.

[chinnerz]

i have looked at your plan and come up with a little something.

you have to close it by hand, and when you do a little rod (green) will move into a hole and will be held there via spring pressure. the actual iron sight (blue/red) is under spring pressure at this point as well.

when you press the button, the green rod is pressed inward, losing its hold on the wall, and allowing the whole sight to move upwards into its operating position.

what do you think?

[FighterAce]

Needs some fine tuning but it could work.. I'll try to give it a shot once I get my hands on some walnut. Thanks

I'd like to point out to just one thing. The whole purpose of BUIS is to have iron sights folded so they dont get in the way of the primary aiming device - a scope in my case. The way you drew it looks like it has no height difference compared to a normal static iron sight when folded. You want those walls to be at the same height as the folded aiming aperture

[chinnerz]

well if you want to point things out... There is no actual sight, its just a box right now. It was just a pre concept design. You could probable make it a bit shoeter and get rid of half of the case wall, that would make it shorter.