Been throwing around some suppressor designs for the MP5SD, let me know what you think and any issues.
Looks interesting--- have these been patented??? :confused:
Your baffles need a reverse scoop on one side to create turbulence of gas in the suppressor. Gas going in two directions “traps” it and makes it quiet
For anyone truly serious about designing suppressors, I would highly suggest one use the skills of a Mechanical Engineer specializing in fluid dynamics.
I don't get the shorter length and smaller OD cans for the SD. I have shot a few different ones and they just seem to leave too much on the table for the size trade-off. (Less db reduction, more blow-back, etc). Factory is 11.89 x 1.57 and even if the goal is to "modernize" the design... Why not take full advantage of volume.
When the Omega 9Ks first came out, numerous people compared the new "marvels of technology" to the MK-9K. Well, I bought one... And then laughed. Nice can, but there is no substitute for volume and no "free lunch" when it comes to suppression.
None the less... Good luck on your project.
My understanding of the original design is there are vents in the muzzle end barrel support. It looks to me that this design entraps the high pressure vent gas. Is the design able to hold that pressure? Also with the thickness of the mount end plate, the powder is still burning at that point. Most SD cans leave the barrel vent area open. I would think that carbon residue from the burning powder would plug the restricted gas ports much more quickly than the original design. Those ports in the barrel become restricted and must be cleaned regularly with the original open design. I would think that the restricted threaded area of the threaded thick area above the threaded base would restrict the barrel vents very quickly, possibly bringing the round to supersonic speeds and causing over function with the rollers pounding the guide rails in the back of the receiver.
Sorry about the delay, been doing a lot of recalculations and re-engineering.
Here is an updated design, but I'm not certain of the barrel nut (spacer C), if it should have vent holes or not.
I have noticed that other newer aftermarket designs have vent holes on the barrel nut.
heads and tails flip
But the original earlier designs did not
So my remaining concerns are; will vent holes in the barrel nut help release pressure and reduce db or increase db?
Can the entire suppressor be made of aluminium or will the pressure be too much? would steel be a better choice? (mind this is for 9mm)
'photo from Sam Pikula'! Ain't that interesting? We all know who Sam Pikula is, don't we?
I think Sam Pikula is a firearms historian and writer, he may have written the AR-10 Saga
I just came across that photo in a search.
His life's story is also very interesting.
... and we now return to our regularly scheduled program ...
So I talked to some mechanics and they say venting the two chambers may be more effective at sound reduction citing various muffler designs.
At the same time, my concearn is that venting would drop too much pressure causing short strokes. Too much and it could cause the aluminum to fail, unless I use steel and I don't have a supplier for that.
If you havenít seen this itís a pretty cool video. Obviously thereís quite a bit more going on inside using a rifle cartridge versus a 9mm.
How do you not have access to steal tubing? ... thereís plenty of places online you can order DOM.
If Iím not mistaken the entire construction, except for the threaded piece that attaches to the barrel, on the HK SD suppressor is aluminum - although Iíve never had one apart.
The cutaway SD suppressor you posted I believe is an early design, note the wall thickness in the first chamber.
The one below is later. If someone knows different please correct me if Iím wrong.
HK SD suppressor (Credit: TPM Outfitters)
Below is the aftermath of not cleaning a suppressor.
In the second pic you can see the layers of carbon as it built up.
Iím not an engineer or suppressor designer but there seem to be a couple of things I would take a look at.
You have exposed barrel threads in chamber 1. These threads are going to fill up with carbon.
Chamber 1 does not fully extend to the end of the barrel. The carbon coming out of the muzzle is going to build up on the outside of the barrel. Iím not seeing any wiggle room right at the area you have marked with the letter D.
If you look at the above picture, barrels on the SD are prone to a lot of carboning.
Both of these could pose a problem removing the suppressor.
Anyway, just my opinion and observation.
I'm sitting in the departure lounge at BIAP to come back to the states after my first rotation with Triple Canopy in 2011 and there's a couple pieces of baggage next to where I platzed. I notice the name "Pikula" stenciled on them, and I'm thinking, "Why is that name familiar?" (it takes a second or two, context, right?) and I think, "Maybe he's got a son over here". I'm so used to being the old guy on a team, right? Most of the guys are 15 years younger than me, or more. A couple minutes later Sam comes back from the can and I ask, "Are you Sam Pikula?" He goes, "It depends, does he owe you money?" LOL. It is of course him, and I say "I read your book!" Channeling George C. Scott playing Patton of course. Bought my copy back in 1999 from him direct by mail when I was living up in Canada, where there happen to be a lot of Dutch Armalite AR-10's, which I am totally into for years.
So we talk a bit while waiting for the flight to be called. Turns out we are both working for TC on the same contract. I mean this guy is like a ****ing rock star in my world, right? I've know who he is for like 15 years already at that point. NEVER expected to meet him, Interweb jabber had him living in Finland or something. So when I get home I got through all my stuff in storage and pull out that copy of his book, take it back with me to have it signed. He does so, and then when I rotate back out the next time a few months later, I put it in my footlocker and mail the whole thing. Of course it never shows up. Was I pissed. The Iraqi's **** us around on our visa's, so I wind up being out for like 4-5 months. The visa thing clears up, I'm still pissed, I give a rat's ass about all the gear in there, I can get more of that. A few days before I'm to head back, the wife goes, "Well, what if they tried to deliver it but couldn't, where would it be?" So I have to figure out what Postal Substation our carrier works out of. I head over there, and make inquiries. The guy goes and finds it, "Oh that's you? That thing's been back there for months, we were supposed to ship it off to unclaimed whatever after 30 days (or something) it shouldn't even have been here". Awesome. I was sure that thing was gone forever.
Very cool Lamont! It’s one of those times where it’s not always bad to meet your hero ;)
@21HK yes I saw that video a couple of times, pretty cool.
I'll change the threading distance but I doubt it would matter as there is a rubber gasket that varies the depth at how much the suppressor screws in depending on the rubber compression. That's why I didn't want to thread short.
I'll consider modifying the barrel but to cover the tip od the barrel
Yes I know the notorious fact if the MP5 SD being a difficult thing to clean.
OK so your aware of the gasket, I didn’t see it pictured or that it was compensated for in your illustration.
There’s no need to consider changing anything, ... as mentioned it was just some observations.
Check out the Swiss army MP5SD suppressor. https://www.hkpro.com/forum/hk-nfa-t...pressor-5.html
If you do it this way, you can add some volume.