Anyone ever seen a hop rubber without the hop patch?

[Rogerborg]

Curious stuff.  I threw an M90 spring, a short barrel, a random hop rubber into my DMR'd Specna Arms and took it to a CQB site.  All good, except for a complete lack of hop.  OK, no worries, I'll just pop in the spare random hop rubber that I thought to bring and... no hop.

Well, no biggie, it was the backup-backup-backup AEG.

But why no hop?

On examination today, it turns out that I'd flat hopped one of the buckings, with the contact bump and most of the keying ridge clearly sanded off, with just enough of its memory remaining to fool me on site in a hurry. I mention this to make it clear that I know what a flat hopped rubber is and what it looks like (inside out, in daylight).

The other, well, it has a clear keying ridge, no signs of cutting or sanding anywhere, but no contact bump.  There's a rectangular section visible where it should be, bounded by straight, very slight lines running along and across it, but they don't look like anything I did or could have done.  It seems like the contact bump is just missing, like it's been pre-flat hopped, but retaining the keying ridge.

The rubber, inside out, showing where the contact bump should be (the ridge is on the opposite side).

View attachment 79973

And highlighting the very faint lines. The cratery bit near the shoulder looks like a tiny moulding imperfection, it's not the result of cutting or sanding, I couldn't do work that fine without scuffing up the whole area.

View attachment 79974

What sorcery is this?  I've checked my purchase history but can't found that I've bought a "flat hop bucking" or anything similar.

What I think this might be, based on the hardness, is a ZCI 70 degree bucking bought from @ak2m4 (and not fitted, it was bought as a backup in case I got DMR Maple Leaf feed issues onsite) although I'll go through my bits box to see if I can find that still packaged elsewhere.  [CORRECTION] No, it's not that, the ZCI has been found and is perfectly fine.

Either way, a bit of a puzzler.  Does anyone make and sell rubbers like this, or have I just ended up with a mutant?

 

[Adolf Hamster]

hmm

removing the keying ridge is a common enough part of the flat-hop process, but as you say it doesn't look like it's been done by hand.

if it were a pre-made flat hop then it would presumably retain the ridge as the only reason it's removed normally is to rotate the bucking to get a fresh contact patch.

a mystery for sure.

also, are the feedlips as torn up as they look in those pics?

 

[Rogerborg]

removing the keying ridge is a common enough part of the flat-hop process, but as you say it doesn't look like it's been done by hand.

Yup, I removed the ridge on the other rubber.  If I'd modified this one, I'd have done it here as well, so I'm pretty sure it came this way.

if it were a pre-made flat hop then it would presumably retain the ridge as the only reason it's removed normally is to rotate the bucking to get a fresh contact patch.

Yup, again. If someone is selling flat hop rubbers, and I've bought one, this is what it would look like.  But I can't find any evidence that I did, or anyone selling them.

also, are the feedlips as torn up as they look in those pics?

Oh, I probably did that while turning it inside out with a set of ridged surgical forceps because sod it.

 

[Adolf Hamster]

Yup, I removed the ridge on the other rubber.  If I'd modified this one, I'd have done it here as well, so I'm pretty sure it came this way.

yeah it does look factory made, although one does wonder why they removed the keying ridge.

Yup, again. If someone is selling flat hop rubbers, and I've bought one, this is what it would look like.  But I can't find any evidence that I did, or anyone selling them.

they're definately a thing, but i'll admit i couldn't specify the brand. any time i've looked i ended up just modding my own or buying something like a maple leaf.

 

[Rogerborg]

yeah it does look factory made, although one does wonder why they removed the keying ridge.

They didn't. To be clear, it's got a an unmodified and distinct keying ridge on it.

It's exactly how you would make a factory flat hop rubber, I just can't find any evidence that I bought it as such.

 

[Adolf Hamster]

They didn't. To be clear, it's got a an unmodified and distinct keying ridge on it.

thought the first pic was showing the markings where the ridge would be but isn't?

now i'm getting even more confused.......

 

[ak2m4]

that is super strange, never seen that before.  I just checked a few of the ones I still have here and they all have the nub and ridge in place.  It's possible that you do have a molded mutant on your hands there

 

[Rogerborg]

thought the first pic was showing the markings where the ridge would be but isn't?

No, the ridge is around on the other side, this is where the contact patch should be.  Those lines are just barely visible but not tangible. Now that I think about it, they're probably just from pushing the rubber on, then the nub trying to push it through the barrel window.

Oh, and I've found what is likely to be the ZCI 70 (apologies to Mr M4), so I suspect this is indeed a factory flat hop rubber.  I just have no idea how I got it, or from where.

 

[Adolf Hamster]

I just have no idea how I got it, or from where.

maybe pulled from a secondhand gun? or if you ever work on other people's guns could be from there?

i know thats where most of my spare parts collection came from.

 

[ak2m4]

@Rogerborg I was going to say that the ZCI 70 is pretty well molded using silicon, the one in the picture looks more like it's made from more of a epdm rubber

 

[Rogerborg]

maybe pulled from a secondhand gun? or if you ever work on other people's guns could be from there?

Hmm, I can't think of any candidates, and it clearly requires use of a flat hopped arm and a thicc eraser nub, or an S/R-hop patch to work at all - it would be (and is) instantly noticeable when used with a standard arm and nub.  I've only got one flat hopped AEG arm, and I did that myself, along with one rubber, and it's not this one.

@Rogerborg I was going to say that the ZCI 70 is pretty well molded using silicon, the one in the picture looks more like it's made from rubber

Good point, the damage on it (the lips and near the shoulder) look like rubber, rather than the smooth splits you tend to get on decent silicone when it gives way.  I'm pretty sure that I've found the ZCI 70 now, and it's better quality than this.

That just makes it even weirder. Why would you manufacture a flat hop rubber (a premium / upgrade piece) out of sub-standard materials?

Small issue, big head scratchings.

 

[Lozart]

Modify do a black flat hop rubber with no nubby bit https://www.skirmshop.co.uk/modify-flat-bucking-black.html maybe it's one of those?

 

[Rogerborg]

Modify do a black flat hop rubber with no nubby bit https://www.skirmshop.co.uk/modify-flat-bucking-black.html maybe it's one of those?

Huh, that is what it looks like, even down to being slightly dry and rough looking (e.g. rubber, "Perfect for using with R-Hop") rather than slick texture (silicone, for direct contact).

But I've got no record nor recollection of ever getting one, or why I'd have done so. My DIY'd flat hop bucking was done to use with an S-hop (tried and abandoned), and I have no other use for one.

@Adolf Hamstercould be right, I might have acquired it some other way than retail, but I'm struggling to think how, as all my AEGs (pauses to check...) were bought new.

Maybe I've just acquired enough Bits in the Box that they are now attracting random parts from hyperspace?

 

[Adolf Hamster]

Maybe I've just acquired enough Bits in the Box that they are now attracting random parts from hyperspace?

quite possible. i have heard it theorized that white holes are responsible for similar phenomena, like the appearance of spoons, mugs, or individual socks despite the owners having never actively obtained such items.

 

[Lozart]

quite possible. i have heard it theorized that white holes are responsible for similar phenomena, like the appearance of spoons, mugs, or individual socks despite the owners having never actively obtained such items.

When everyone had tape decks in their cars there was a phenomenon whereby once you had enough cassettes in your glove box, one of them would mutate into a copy of Queen's Greatest Hits. Probably the same pixies at work here.

 

[Steveocee]

Modify do the Baton Ryukosu (sp) rubbers which are in 2 flavours, soft and hard (grey and black) and they are perfectly smooth. I believe Laylax also did one as well.

Maybe you just happened upon a perfect flaw on a moulding? Doubtful but maybe. It would work pretty well if you had a beefier nub I'd bet though.

 

[Hudson]

Laylax extra soft flat bucking, perhaps? 

 

[Rogerborg]

Modify do the Baton Ryukosu (sp) rubbers which are in 2 flavours, soft and hard (grey and black) and they are perfectly smooth

Yup, @Lozartflagged that earlier, it does look like the black one, and is quite hard - which is why I thought it might be a ZCI 70.

Oh, hold the phone! I know where I've seen that style of nub before...

In this very Specna Arms SA-E02 Edge.  Clearish rather than black, but that profile, I'd never seen one like that before, and that does seem to be advertised as a flat hop nub.

Well, I reckon this could be the stock Specna bucking then, which I replaced with a Maple Leaf bucking and Omega nub right out of the box.  I'd never seen them advertised as having a flat hop bucking, but mine did come with that style of nub, and I'm fresh out of ideas as to where else this bucking could have come from.

I wonder if anyone with a stock Specna could shed any light on it.

Laylax extra soft flat bucking, perhaps? 

No, it's quite hard and stiff.  Fnar.

 

[Lozart]

No, it's quite hard and stiff.  Fnar.

View attachment 79984

 

[Adolf Hamster]

No, it's quite hard and stiff.  Fnar.

yeah if that persists you might wanna talk to a doctor about that....