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Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



. . . . I've come to talk to you again.



Because a vision softly creeping



Left its seeds while I was sleeping



And the vision that was planted in my brain



Still remains

Time to get . . . my Dremel.

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tarlibone
Aug 1, 2014

Am I a... bad person?
AM I??





Fun Shoe

Love the song spoof.

But for this of us who were late to class... what was the result of the endremeling?

kupachek
Aug 5, 2015

We both like to hang out in public bathrooms?!


This place is not a place of honor... no highly esteemed deed is commemorated here... nothing valued is here.

What is here was dangerous and repulsive to us. This message is a warning about danger.


You monster!

Admiral Bosch
Apr 19, 2007
Who is Admiral Aken Bosch, and what is that old scoundrel up to?

Excellent. You said in the main sig thread you were having a clearance issue with the elevation screw somehow, if you could take a picture I'll try to compare it to mine. I don't recall having any issues.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



tarlibone posted:

Love the song spoof.

But for this of us who were late to class... what was the result of the endremeling?

Don't worry, that's coming. I just wanted to get it started with a dumb poo poo post.


Admiral Bosch posted:

Excellent. You said in the main sig thread you were having a clearance issue with the elevation screw somehow, if you could take a picture I'll try to compare it to mine. I don't recall having any issues.

I'll go into depth about that. I've got some . . .opinions about how this was designed at this point. The tl;dr is that I suspect you pulled more material out milling it than I did initially, but I'm not sure.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



So a bit of background to start with.

I won't get too far into the weeds, but a bunch of years ago SIG USA released what a lot of people thought was going to be a semi-auto, American made (hence no import ban) clone of the SG 550, a rifle that people have lusted after for a long time.

This is an SG 550:



What they came out with was, well, this:



The SIG 556. The internals were mostly like a 550, and in the beginning they were shipping with some actual SIG parts (bolts commonly, iirc) but the whole thing is just . . .blech. Re-doing the mag well to take STANAGs is actually kinda understandable given the American market, but ditching the side-folder in favor of an AR stock was unforgivable. The biggest reason why this was such a fuckup is that it fundamentally changed the way you look down the gun. The 550 has a lower stock comb than an AR, due in large part to not having a buffer tube, which means that the new 556 ended up needing AR-height sights, which just made the whole thing weird. Oh and that handguard was hot garbage, just chunky and made of bottle-cap grade plastic. There were ways to un-gently caress them, but it usually involved buying a whole new lower from Switzerland (the upper is the controlled, serialed part on these). If you want to see a thread with someone doing that with a P556 pistol, check out smax's work in progress thread on exactly that kind of project. In the end they tried to release a gun that the AR crowd would take to because it could use AR accessories, but ended up alienating the people who wanted an actual 550, while the AR guys just kinda ignored it because, well, ARs are pretty good guns if you want a gun that uses AR accessories. They found a slight niche among people who wanted a piston gun that takes AR stuff, but on the whole it was a flop.

A few years later they released this, the SIG 551-A1. It's basically them trying really, really hard to get a do-over on pissing off the people who wanted a 550 pattern gun.



It was much, much better. The lower is American made and aluminum, which isn't the stamped metal most people think of when they think a 550 pattern gun, but it's also something that the Swiss are doing too. The stock was initially a swiss made stock right off the 550 lines, but eventually they switched to a cheaper, flimsier American made model. It takes the swiss SG550 mags. The handguard is styled more along the lines of the SG550, although it was kinda chunky and still made of bad plastic. Still, better than the old "fishgill" ones. On the whole it was a good gun, but not a perfect gun. I bought one of these when they first came out and got one with the swiss folding stock. A buddy in Switzerland hooked me up with some swiss handguards, and before too long I had a pretty decent setup.

The problem was the drum sight that SIG included was kinda poo poo. It sat on top of the rail and was really, really high. If you look at those pics you'll see that the American front sight sits way higher than the swiss ones. For whatever reason they kept the AR sight height. This mean that getting a good cheek weld was now fairly difficult due to slope on the stock comb.

Meanwhile there was an actual combination rail+rear sight that you could get in Switzerland, but cost near $500. You pretty quickly saw a few small outfits come out with better diopter sights. Aurora was one of them, and I got a pair of those (since sold before anyone asks) that worked for a long time. Proper height. Didn't look swiss, but it was close enough.

Then, MFI came out with these:

https://mfiap.com/i-23899865-mfi-si...ority-mail.html



Cosmetically they look very close to the swiss rear sights. They're integral to the rail, so you just unscrew the rail on your rifle, pop these on, and you're good to go. The sight height is right, and they even have a silly little swiss cross on them. What's not to love? They were a bit pricy at $400, but still cheaper than swiss and pretty quickly they got marked down to $250. That's how much I bought mine for, and for a good while I was pretty OK with them. They were . . . good enough.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



The MFI sights

Cyrano4747 posted:

What's not to love?

Well, a lot. Some of it is kind of dumb but pretty emblematic of the level of thought that went into making these very expensive irons.

First off, look at the elevation adjustment pictograms, a stripped SG 550 rear sight on the bottom and a the stripped MFI sight on top:



They're nonsensical.

Other issues:

1) the drum wobbles a bit left to right in the base. It's not a ton of play, and I never noticed it majorly affecting accuracy, but it's disconcerting. The real Swiss ones are rock solid.

2) the elevation adjustment is a simple screw. The Swiss one has a wheel at the bottom that is pushed on by a rather stiff spring, providing some very robust clicks, and helping it to stay in place. I DID have issues with this screw walking during firing, and my sight moving around vertically. In the end I loc-tite'd the elevation adjustment after I got it zeroed for 100, but that's obviously not a great solution.

3) less important but still annoying is that the different, numbered drum apertures are basically a cargo cult of the swiss sight. The swiss sight has a v-notch numbered 1, and then 3 apertures numbered 2, 3, and 4. Those numbers aren't just for show, they're basically easy elevation adjustments for that many hundreds of meters. So get yourself a zero you like (say, by zeroing at the 50 yard line with the 200 meter diopter) and then, bam, you've got some really handy pre-sets for other common distances. On the MFI sight they're all at the same height and basically pointless.

4) even less important but still annoying is that the drum has an extremely soft and mushy click when you rotate it. It's solid as gently caress on the Swiss sights. I mean, you're not going to rotate it anyways because the different apertures are basically cosmetic, but hey, would be nice to have.

A few years later I there was a company selling actual, no bullshit SG550 (or 551/2/etc, not sure, doesn't matter for the purposes of this) rear trunnions and receiver stubs with the iron sights on them. I had the idea to buy one and see if I couldn't swap some of the parts over. Well, that wasn't as simple as a drop-in. There's some pretty major differences in construction, which I'll outline in a post that anyone who doesn't care about the details can skip (and which I'm just quoting from the SIG thread where we already discussed this).

The tl;dr is that the MFI rear sight has a floor built into the bottom of it in line with where the rail is. This is the direct cause of a lot of the dumb design compromises that had to be made (lack of adjustment detent most notably) and if you want to put the Swiss stuff in you need to drill it out.

Admiral Bosch has already done this using fancy poo poo like "a mill" and "proper tools" and "responsible decision making"

I am not Admiral Bosch, and we will not be doing those things in this thread

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Ok, here's a re-post of the comparison between the sights if anyone's interested. Feel free to just skip this entire post unless you're really curious about what the differences are.

As I said before, the tl;dr is "Cyrano's gotta cut the bottom out of that $250 (on sale from $400) rear sight"

Cyrano4747 posted:

Ok, the TL;DR is that the guy made the MSI sights different in some specific and very odd ways. I suspect to ease manufacturing with it attached to the rail, but I'm not sure.

Disassembly is basically as I described above, except that it comes out much easier. Mostly because poo poo isnít held in as well, which is part of why we have this wobble.

The first major sign that things weren't going to work: note the different location of the detent. It's also not housed in the rear sight assembly itself, but in the body. Swiss sight next to it for reference.



Just the MFI sight. The drum is in the background. We'll come back to this.



The two drums next to each other. The bottom hole on the right of swiss one (all Swiss stuff on the left in these shots) is where the detent goes. Note how much deeper the swiss sight is, due to the click detent on the bottom of the elevation adjustment. That part is a simple screw on the MFI sight, which makes it shallower.



Bottom of the two bases. Note also how the swiss sight is held in differently. Frankly I think the screw on the MFI introduces some play.



If you really want an illustration of the differing quality, check out the detents and springs.



Here's the crux of the matter: The inside of the rear sight bodies. Swiss on bottom, MFI on top. NOte that ledge in the rear of the MFI sight - that's where the elevation adjustment rests, and it's just not there in the MFI. The spring on the swiss one is slightly longer as well. I suspect that if you milled out that ledge and (maybe) trimmed about 2mm off the edge of the swiss drum's spring you could get it to fit, but I'm not 100% sure. At any rate it's more than I can do right now and I'd want to ponder it some more before carving up my MFI sight. You'd probably also have to open up the slot at the rear of the sight that the tab on the elevation adjustment sits in. Not impossible, probably very doable for someone with actual mechanical skills, but more than I want to try freehanding with a dremel right now.



That little box in the upper left of the MFI sight is where the detent sits. I don't THINK that would be a problem. You'd be stuck using the MFI detent , but it should work with the swiss windage drum as the holes are in basically the same spot. If not, simple matter of drilling a hole for the swiss detent. Again, not something I'm working on today.

Just for comparison's sake the two windage drums. Swiss one on the right this time because I'm an idiot. Note how much finer the threads are.



So, at the end of the day I think you could make the swiss guts work with the MFI sight, but it's a bit more complicated than just dropping poo poo in. At the end of the day I suspect it might be easier to crack the welds holding the SAN sight base onto that trunnion stub and pay someone a few bucks to weld it to a chunk of rail.

Note that if you click through on that quote there's some additional swiss rifle rear sight nerd chat with people who are interested in sight replacements (smax), people who know what they're doing (Admiral Bosch) and people who are YOLO'ing poo poo (me).

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Ok, now that we've got all that stuff out of the way, let's get moving on making bad decisions.

First problem: I don't own a drill press, much less one that can be used as a mill. God knows that would make this easier and more precise.

Solution: I own both a suburban home depot-grade cordless drill and a dremel, and my hands don't shake too much.

Second problem: I don't own a vise, although I'm shopping for one. I should probably kick the can on this until I've spent the princely sum of $50 on a light duty vice, huh?

Solution: YOLO I've got these C-clamps and hey, they've even got a nice little rubber foot on them so I don't mar my rails.



BRR goes the hand drill



Fast forward a bit and I've upgraded to using a bigger bit and I've also upgraded my bench clamping game by ripping a piece of wood off an old pallet I had nearby (no, really) because I didn't totally trust the rubber thing on that clamp to not scratch poo poo.



At this point I started going ham on the inside with a pair of files. Why? Because I wanted to get the opening in the middle a bit wider.



Not bad. Drill out a few smaller holes near the edge and I think we're just about ready.



What for? The hacksaw.



You may have noticed that the blade is in backwards. That's so I could use a pulling motion towards myself while standing above it and keep a better eye on what I was cutting.

Zip zip goes the hacksaw, then we get up in there with the files a bit more, and before you know it we've got this roughed out:



It's basically the same thing as the swiss one now, a fine example of precision craftsmanship and attention to detail.

A quick test fitting shows that, hey, I'm not completely off bases. That poo poo fits in there.



As an aside, note the little splash of silver on the edge where I brushed it with a file or a spinning bit of drill or something. Oh well, it's just paint.

No, really, those $400/250 on sale rear sights weren't anodized or anything. That's black paint.

Cyrano4747 fucked around with this message at 18:34 on Jun 22, 2021

Somebody Awful
Nov 27, 2011

BORN TO DIE
HAIG IS A FUCK
Kill Em All 1917
I am trench man
410,757,864,530 SHELLS FIRED




How I feel right now:

https://www.youtube.com/watch?v=g3A7okQlHP8

The Automator
Jan 16, 2009


What the gently caress are you serious

JRay88
Jan 4, 2013


Miller Lite really sets this thread up perfect

Wifi Toilet
Oct 1, 2004



Toilet Rascal

and lo, the son becomes his father

madeintaipei
Jul 13, 2012



Wifi Toilet posted:

and lo, the son becomes his father

Not enough JB Weld. We have a ways to go before the student usurps the master.

Admiral Bosch
Apr 19, 2007
Who is Admiral Aken Bosch, and what is that old scoundrel up to?

I'm screaming a little inside. Good work(???) so far, but if you want to clean up the sides of the sight base a small flat file will probably do you up right for pretty cheap. (This may also help alleviate your elevation screw issue mentioned up at the top).

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



The elevation adjustment problem

Now that we've roughed out the inside and gotten the drum to physically fit in the housing, it's time to look at what areas are actually dimensionally important for this. The first area of concern is the part alongside the left side (when viewed from the bottom or behind - i.e. shooter's view) of the housing where the elevation adjustment bumps up against it.

When I first installed the sight after roughing everything out the elevation adjustment was extremely sticky. I could click it, but I had to put enough pressure on it that I was afraid I was going to break something. Not idea, and certainly not something you're going to be adjusting at the range.

Admiral Bosch posted:

Excellent. You said in the main sig thread you were having a clearance issue with the elevation screw somehow, if you could take a picture I'll try to compare it to mine. I don't recall having any issues.

Here's the culprit:



You can see how the click adjustments work here. The bottom of the screw has that wheel thing on it, which has notches. There's a leaf spring that puts tension on it, and a knob that acts as basically a detent to give you the "click." The material left in the side of the housing prevents that spring from moving outwards, which means that while it will eventually click (I suspect because the screw deflects in the other direction rather than the spring) it's hard as gently caress.

So that's going to have to be trimmed back pretty extensively.

The other issue is that when I installed the rail I never got it flush with the receiver. It wasn't deflected too much, but it was noticeable. Wish I'd gotten a picture of that.

I noticed when comparing the MFI rear sight to the SIG one that the spring on the SIG sight was significantly longer. And, sure enough:



You can see the ledge that the MFI drum's spring sits in and how the SIG one goes out past it.

A bit of time, a lot of filing, and a bunch of movie watching later (I'm watching only the finest of cinema while doing the more tedious fitting on these - right now I'm 4 of 5 movies deep in the Resident Evil franchise) and here's what I've got.

You can see that the slot for the drum's main spring is now longer, and I've filed back the edges of the inside in general to give the drum assembly more clearance.



It's not a precision fit, but it's good enough to put everything together and see how it works.



Better, but still not quite right. First off, due to using everyone's favorite rotary tool to carve out that channel it's shallower towards the leading edge (where the tip of the spring sits in the above pic) than it is towards the drum. This is better than before, but still not ideal as it's still not letting the rail sit flush:



See that bit of daylight under the rail just ahead of the sight base? That's not great. (I'll touch on this in a second post in a moment)

As for the elevation adjustment on the drum, it's better but still not great. When the sight is cranked all the way to the right the pressure is relieved and it works as it should, but anywhere close to the middle of the sight and, well:



Still making contact.

The problem is in how the sight housing was constructed. Here's a picture of the SIG sight's housing to illustrate:



The interior of the swiss sight is hollow, with the sheet metal body being folded over itself to create the top surface that the pictograms are on. If you cross sectioned it it would look like an inverted capital L. The MFI sight, meanwhile, is a solid chunk of aluminum that has the exterior walls of the sight base a uniform thickness throughout. I'm pretty sure it was cast and then (maybe) had a little finish milling on some of the critical surfaces. What this means is that there's significantly less interior volume for the drum. I'm pretty confident that this is what drove the decision to not have click adjustable elevation adjustment. That would have required milling some material out from underneath, and that would either be more expensive or potentially weaken the material in a way that could lead to more breakage, returns, etc (again, more on this in a later post).

My solution? Break out the files again and under-cut that ledge, while being careful not to remove enough material that I A) break the sight housing or b) cut into the top ledge and obliterate the markings. I mean, they're dumb and pointless, but I might as well leave them there for now.



A bunch of filing later and here's what we've got. It's a bit hard to photograph, but end-on like this you can see that there is a slope there. You can also see how I've further extended the channel for the spring. No, it's not pretty, but all that poo poo's not going to be visible when it's put back together. Also I'm not worried about hollowing out the bottom of that rail since the aluminum is plenty thick and it's not something that takes any kind of a load.



Some early fiddling shows that this is probably going to work, but it's going to be a lot of filing, fitting, filing again, etc.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



WTF MFI

So, a general word on the quality of this rail/sight combo:

it's kinda poo poo.

Don't get me wrong, it's adequate to the tasks of "looking swiss, kinda" and "being a rear sight." But goddamn every corner that could be cut, was. The aluminum, for example, is really soft. I mean, all aluminum is soft but this stuff feels softer than normal.

But the real crime is the general build quality of the rail/base unit. It's cast with a very minimal amount of machining MAYBE done on a few of the more critical surfaces (inside surfaces of the rail, for example). On the whole it's a mess of seams and dumb little oddities of geometry that are just making my life harder than it needs to be.

Maybe all of this was necessary to get it to cost a semi-reasonable amount due to the presumably low volume, but man this thing has every corner cut that they could find.

Admiral Bosch
Apr 19, 2007
Who is Admiral Aken Bosch, and what is that old scoundrel up to?

Yeah, whatever alloy he used it's definitely not anything resembling aircraft grade/6000 series.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Itís a loving sign.

Here I am whittling on some aluminum with the consistency of a bar of Irish Spring and whatís this on my mindless entertainment of choice?



A 551 with a rail and a dot. Now Iím trying to figure out what sight model that is.

(Cinematic masterpiece Resident Evil: Retribution, for the curious. Itís a lesser RE film but not bad. Not as good as RE Apocalypse, not as bad as RE Afterlife.)

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



My bad itís a 552. They really went for a lot of close up zooms on actors faces in this. Which is puzzling given the fact that the quality of acting is sub-porno.

The Automator
Jan 16, 2009


Is that supposed to be Leon Kennedy?

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Yuuuuup

Dr. Gojo Shioji
Apr 22, 2004



I wish I could talk to movie armorers about the SG 550 series. I swear that outside of Ronin and Miami Vice, they're used exclusively by mooks and henchmen. Just take a look at it on IMFDB and you'll see that it almost exclusively appears in the hands of organized criminals and "elite" bad guy forces. The Cabin in the Woods, Jurassic World: Fallen Kingdom, Nobody, John Wick 2, The A Team. It's like the 551/552 got typecast as the slick, faceless gun for slick, faceless enemies destined to be mowed down by the protagonist.

large hands
Jan 24, 2006


somewhere on the side of a flowery meadow, mikerock sheds a single tear

madeintaipei
Jul 13, 2012



large hands posted:

somewhere on the side of a flowery meadow, mikerock sheds a single tear

Ew.

Oh poo poo, username/post.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Minor update:

After a bunch of filing I've got a better, but still not ideal, fit for the elevation adjustment.



In the process of cleaning up the internal surfaces I've also had the occasional errant file strike. Nothing that majorly changes the edge shape or anything, but still ugly. MOST of this shouldn't be visible when it's put back together, but it's also going to be on a site so errant bits of shiny aluminum heading for your eyes could be annoying to say the least.



So, I went on Amazon and ordered the very cheapest black acrylic paint I could find. I think this bottle cost me $3.

In the interest of science I went ahead and swiped a file across the underside of the rail a few times to take the paint off and test this stuff out. It's not a surface that's ever going to be visible so if this doesn't work, gently caress it.



Incidentally, notice how the (flat) file only hit the edges of the rail? More MFI precision. That thing isn't exactly perfectly flat. It doesn't really matter as long as its stable, but still.

A little paint and a few minutes later:



Not bad. Apparently "literally the cheapest black, gloss acrylic paint I could find" is a pretty good match for what MFI was using. Adheres about as well too. Don't get me wrong, I can get this off with my thumbnail, but then I also did zero prep. I'll probably get better results if I give it a good wash, since all this has gotten years of incidental gun oil. That picture is actually a little unflattering due to the light reflecting off it. In normal lighting it's not nearly as easy to spot. Should work fine for small touch ups, at the very least.

Now, just so you don't think I'm getting all fancy and responsible worrying about my finish, I should note that after the paint bottle got here I realized that I haven't owned appropriately sized paintbrushes for this work in something like 20 years.

So, a quick trip to the bathroom later, here was my paintbrush:



Next up: I put on my thinking cap to try and figure out how to get the windage detent to work, the one bit that Admiral Bosch wasn't able to figure out.

Admiral Bosch
Apr 19, 2007
Who is Admiral Aken Bosch, and what is that old scoundrel up to?

I do have some thoughts on that - assuming you put the new hole for the detent in the correct spot(and assuming i did) the trouble is that the 'ear' of the sight base is a little too thick for the detent to reach through and engage the points on the inside of the windage screw. So now that you have your handy dandy sharpie tactical black paint you could probably flat file it down by like .010 or .015, repaint it, and it might work. I may end up trying that soon as I'm at a loss on how to do it otherwise.

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Admiral Bosch posted:

I do have some thoughts on that - assuming you put the new hole for the detent in the correct spot(and assuming i did) the trouble is that the 'ear' of the sight base is a little too thick for the detent to reach through and engage the points on the inside of the windage screw. So now that you have your handy dandy sharpie tactical black paint you could probably flat file it down by like .010 or .015, repaint it, and it might work. I may end up trying that soon as I'm at a loss on how to do it otherwise.

Yep, that's the basic plan.

dubzee
Oct 23, 2008



Baby Jebus weeps.

For erasing thinnish bits of aluminum on the cheap:

https://www.harborfreight.com/43-amp-14-in-long-shaft-die-grinder-60656.html

https://www.harborfreight.com/2-in-aluma-cut-genuine-solid-carbide-burrs-4-pc-56406.html

Godspeed, brave mod man. Big ups on the Miller Lite, BTW. I'm a PBR dude myself, no shame in the cheap beer game.



(edit) just noticed my lag in posting dates. hope you got it sorted

Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



OK, a few updates on this.

I did a bunch of napkin math to try and figure out where, exactly, that detent hole should go:



As you can see, the detent has larger OD than the actual detent itself, providing a shoulder that needs to rest against a recess on the inside of the sight base. Put simply, the issue isn't just drilling a hole, it's recessing the back of it for the detent:



So, after doing my level best to try and locate exactly where the main hole should go, it's time for the drill:



That part was easy enough, provided I got the hole in the right place (which is an admittedly big "if").


The hole is the right size for the pin part of it at least:



I also realized that the spring needs to move ever so slightly laterally when the rear sight moves, so I expanded the notch I cut in the base of the rail. Sloppy work, but all this will be covered up and none of it is really imporant as far as the rigidity or strength of all this goes.



So, then, how to get this detent working? As you can see here the aluminum is just barely too thick. At its current thickness the end of it sits almost flush. (detent being put in backwards to illustrate this).



The answer?

Filing.



A LOT of filing, a little bit at a time, because you really don't want to thin this out too much. The whole time I was doing this I was afraid I'd go too far and the ear would snap when I tried to adjust the rear sight.



You may notice the hole looks a bit hogged out in that first shot. That's because it is. I miss-aligned the hole ever so slightly, but the problem was solvable by hogging it out to the side a little bit. Not elegant, but it worked.

I did a basic test fit and holy poo poo it works. Don't get me wrong, it doesn't feel like the real swiss one. The click is a bit mushy but it is 100% there. Here you can see it in action.

Here's the sight locked into one of the windage clicks:



And here it is half way between two of them. Compare the shots and you'll be able to see that the detent is pushed out slightly when it's between clicks.



Slather a bunch of black paint on all the exposed aluminum and it's time to get this together and test it out.



The first test fitting showed that it was still binding a bit on the rear, where that over-hang I described in the last post was. So pull it all apart, and file that back even further. I got pretty aggressive here, but the aluminum in this chunk is pretty beefy so I had material to work with.



More paint, more reassembly, and we're good to test this poo poo out.

Admiral Bosch
Apr 19, 2007
Who is Admiral Aken Bosch, and what is that old scoundrel up to?

Hell yeah, glad it worked. The too-much-tension on the ear issue is something I hadn't even considered... There's gotta be some other way to do this a little cleaner, I just haven't worked it out in my head.

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Cyrano4747
Sep 25, 2006

Behind every great engineer is someone just hoping the "genius" doesn't bankrupt everyone.



Admiral Bosch posted:

Hell yeah, glad it worked. The too-much-tension on the ear issue is something I hadn't even considered... There's gotta be some other way to do this a little cleaner, I just haven't worked it out in my head.

Honestly I don't think the squeeze is worth the juice. It works just fine without the detent clicks, and while it certainly feels nicer, it's just so much extra goddamned work.

Plus one small issue that I'm going to address in another post after I deal with post-range trip poo poo. Maybe tomorrow if I'm lazy. (literally just got in the door)

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