An issue with underbarrel shotguns
 

It seems to be becoming the norm here to identify any shotgun in an underbarrel configuration as a Masterkey, even if it isn't one. I bring three examples, all listed as "KAC Masterkey" on their respective pages.

http://www.imfdb.org/w/images/a/a3/GRFS-MASTERKY.jpg
The UBS in Future Soldier is listed as a Masterkey, but the fact that it's clearly semi-auto and lacks M203 style mounting brackets means it isn't.

http://www.imfdb.org/w/images/0/0d/M...CMasterkey.jpg
The UBS in MGS4, while technically a Remington 870, lacks M203 style mounting brackets, instead attaching via an RIS mount, and as such isn't a Masterkey. To my knowledge, no such configuration of the Masterkey exists.

http://www.imfdb.org/w/images/6/61/CODBO3.jpg
The UBS in Black Ops similarly has no M203 style mounts in addition to having a full-length barrel, which no full-length version of the Masterkey exists to my knowledge. So hence it can't be a Masterkey either.

I feel we need to start being a bit more conservative when it comes to identifying underbarrel shotguns. We don't label every underbarrel grenade launcher on IMFDB as an M203, do we? A similar principle applies to using terms like "Masterkey style" in reference to underbarrel shotguns, as we don't refer to the likes of the AG-36 and GP30 as attaching "M203 style" to their respective parent rifles.

I know that there are multiple manufacturers of underbarreled 12 gauge mounts.

The underbarreled shotgun in Predator seems to have been built by Arthur Cleiner

You have the KAC Masterkey which uses a modified M203 Mount.

You have the mount for the Remington 870MPS.

Then you have a bunch of videogame stuff which does not exist IRL.

Actually, that one is a Masterkey, albeit with the upper parts of the mounting missing. You can actually see at the front of the "rail adaptor" is the point where the missing front bracket is supposed to fit.

I guess that was done because, as you see in the image, the bracket doesn't physically fit on the rifle model when the suppressor is attached. I'll have to check if it's there if you detach the suppressor. Sticking a UBS with an obvious bracket mounting on a railed handguard is just one of those things that works a lot better in a videogame than it does in real life.

The bracket mounting point is too far ahead of the barrel step to fit it, though. Then there's also the matter of the missing rear mounting point, which isn't removable.

It's not. The shotgun attaches directly to the bottom rail.

Is it possible the MGS4 KAC Masterkey based off of an airsoft accessory? That could be the reason why it was modelled as attaching to the underside rail (which would tear or break from the force of firing if it were real and loaded with live ammunition, but would present no problem with airsoft pellets).

Well sure, but that still makes it a badly rendered Masterkey rather than not one. The front bracket mounting is there, looks like they used a photo of an attached Masterkey as a reference, didn't realise it wasn't just attached to the bottom of the handguard, and removed the front bracket from the model because it didn't fit when the suppressor is fitted.

I checked, but what I found was some guy who'd made a replica of the MGS4 M4 / Masterkey saying he'd had to make the mounting himself because there was nothing on sale like it. I think it's a more simple scenario of the designer not realising a standard Masterkey isn't a rail attachment and so rendering it in game as if it is one.

That is plausible. I hadn't considered it until just now.

But a Google search only brings up a few pics of a custom-build replica of the M4 Custom.

http://forums.zeroin.co.uk/showthrea...099#post418099

The only non-cosmetic difference between this build and the in-game gun is that the supposed fore attachment point on the replica is in line with the barrel step.

But I haven't found anything to indicate this is a mass-produced item.

He actually says in that post that the mounting is bespoke (it's posh for "custom") which I assume means he made it himself or had it made specially, which indicates there's no available mounting that looks like that.

But I'd maintain this is different to the usual small rail mount "masterkey" seen in games (which I agree should be labelled as something else); this was clearly modelled after a full-size bracket mount with the attachment point for the front bracket still visible.