H&K MP5SD: The Cadillac of Suppressed Submachine Guns

hey guys thanks for tuning in to another video on forgottenweapons.com i'm ian mccollum i'm here today at morphe's and we have something i'm sure you've already recognized this is an hk mp5 sd this is the integrally suppressed version of i'll go ahead and say it the best submachine gun ever made this was developed in or originally introduced in 1968 as a follow-on version to the regular mp5 because there were some special operations sorts of guys in the german military who wanted a suppressed version and so hk went to work figuring out what they could do to make this reality and it's a little more complicated than just tossing a suppressor on the end of the gun because they wanted to make you know there are a couple uh things that they had to account for and one of them is the fact that standard military use nine millimeter ammunition is supersonic and if you want a properly effective suppressed weapon you have to reduce that you have to have a subsonic projectile otherwise no matter what you do with the muzzle blast and the pressurized gas coming out of the barrel you can't avoid the fact that you'll get a sonic crack from the bullet if it's breaking the sound barrier and that's louder than you may recognize um that's a significant element of the noise of a firearm so if you want a properly suppressed weapon it has to be subsonic but what if you don't want to have to have two types of ammunition you want to be able to use standard nine millimeter but make it subsonic well hk's uh solution for doing that was to use a special barrel design where they have actually drilled a bunch of holes right in front of the chamber so as soon as the bullet starts accelerating down the barrel instead of all the gas pressure pushing the bullet a bunch of it is immediately vented out into the rear chamber of the suppressor that drops the pressure in the chamber behind the bullet and that reduces the maximum velocity that the bullet will obtain in theory reducing it below the speed of sound we'll try that out tomorrow more on that in a moment now the original suppressor design that hk came up with uh used a wire mesh pack basically and this was a suppressor design that had been used in world war ii the us m3 grease gun uses it if you're curious about that i have a video on the suppressed grease gun that you can check out the problem for hk was they found that that wire mesh got like thoroughly fouled to the point that it was no longer fully effective in something like 70 rounds and and then had to be taken apart and cleaned and that wasn't acceptable so they needed a new version of the suppressor so let's take a closer look at the gun itself i want to show you a couple of the features up here where it's different from a standard mp5 and i have a picture of a section suppressor from this so i can explain to you exactly how they made the final production version just for comparison's sake to start here this is a standard mp5 this is actually a semi-auto short barreled rifle but all the dimensions and layout of a standard mp5 and here is the mp5sd so the receiver is the same the sight radius is the same the sights themselves are the same however the handguard has been replaced with this cylindrical model and the suppressor sticks out quite a ways now the barrel on the sd is only 5.7 inches long so it comes to about here really everything from here back on the gun is the same so it uses all the same standard magazines typically 30 round 9 by 19 parabellum of course now it's when we get out here that things get a little bit different so we have this rather grippy handguard that's an insulator that's applied to the outside of the actual handguard if this looks familiar to you from other places it is because the like the one existing pancorp jackhammer shotgun was retrofitted to have one of these grips on the front of it to give it a little more texture so you may recognize this from the pancore jackhammer and that's why they used an mp5sd part there now the suppressor that's the real part here the important part you'll notice the very end of this is actually textured and that's to give you grip so that you can there we go unscrew it because this comes right off and if we take a look down there you can see that the barrel is rather shorter than the handguard itself now at the base of the barrel are a number of vent holes which you just can't see here and there's no easy way to take the handguard assembly off so instead we will take a look at a cutaway suppressor this version of the suppressor was developed between 1970 and 1972 in response to the longevity issues that the original wire mesh type had so what we have here is a two-part suppressor there's a a first chamber back here that's just an open first chamber and that's what takes the gas initially vented when the bullet fires and just allows pressure to drop to slow the bullet down out here is where the real meat of the suppressor is and this is actually sort of a coaxial design where there is an outer aluminum tube the whole thing is aluminum by the way and then there is an intersection that is made of actually aluminum square tubing that is cut and bent into a series of v-shaped asymmetrical baffles and so this actually makes it especially at the time a very easily manufacturable assembly there isn't a lot of you know stamping out individual baffles and then having to weld them in place the whole baffle stack was made as one continuous part out of plain drawn aluminum square steel tubing now you can see those v-shaped baffles in there from the side those are asymmetrical you'll notice the top and bottom are of different lengths that helps to add turbulence to the gas basically anything that is going to keep the gas inside the suppressor moving around before it finds its way to the the exit at the front is going to reduce the eventual pressure uh when the gas does come out and it's going to make the gun quieter so um hk is maybe a little touchy about the interior design here this picture by the way is uh was taken at the mauser museum in obernorf by me and so hk didn't give me a picture of this but i found one anyway and i think it's a really interesting internal design to the suppressor that i am not a suppressor expert yet but it's uh rather different than a lot of the other designs on the market so and dates all the way back to the early 1970s which is really pretty cool and frankly i think it helps explain how the sd achieved its position of dominance in the market it really just was an excellent suppressor for when it was manufactured so we can go ahead and put this thing back together pretty easily just drop that on thread it down and there we go we're ready to uh ready to go i'm pretty sure the mp5sd has been featured in every video game ever made and i think it's been in most of the action movies ever made it is an extremely recognizable suppressed submachine gun that basically anyone you show this to who knows what it is they will agree that yeah that's pretty much best of best of breed for a suppressed submachine gun there really isn't a whole lot of there aren't a whole lot of competitors uh nipping at the heels of the mp5sd so uh it was very cool to get a chance to take a look at this one very happy to find a proper original hk one that i can show to you guys and uh i'm really kind of curious about how effective that barrel is in actually reducing bullet velocity so we're gonna go ahead and take this guy out to the range and try it out tomorrow so stick around for that thanks for watching

Channel: Forgotten Weapons

Views: 214,150

Rating: 4.985055 out of 5

Keywords: history, development, mccollum, forgotten weapons, design, disassembly, mp5, mp5sd, shalldampfer, silenced, suppressed, suppressor, silencer, smg, subgun, submachine gun, 9mm, subsonic, supersonic, integral, h&k, heckler, koch, best smg, gsg9, special forces, burst

Id: snDWL4PvEp8

Length: 8min 5sec (485 seconds)

Published: Fri Nov 13 2020

Reddit Comments

[u/HeckMyManDan]

Very excited to hear what it sounds like at the range

[u/Mickey-Maus]

Needs an under-barrel grenade launcher.

[u/zardoz342]

he say Cadillac but he mean lexus