300BLK Integral Suppressor

[LostintheAOs]

I'm in the planning stages of a 300BLK integral suppressor. I've come up with a basic design that uses "baffles" drilled directly into the barrel itself (eliminating alignment issues). I saw this done on a 10/22 and am curious if it will work for 300BLK as well. The can itself will be 2" OD welded stainless pipe with a .065" wall thickness. I haven't yet figured out how to do the baffle plates yet (in between the ports). The original design was intended for a SMLE in 45ACP (De Lisle Carbine), hence the can hanging low on the barrel. The first row of ports would be angled back at around 45*, directing the initial surge of gas into the largest portion of the can (I'm thinking those should be bigger than they are in the drawing). Also, the first 3 rows (as drawn) are "T" ports (down as well as across). This is just a rough idea to start with, so feel free to rip it apart or give new ideas. Thanks.

[Kuraki]

Is this for an AR or Bolt gun? If for an AR I would do it on center instead of eccentric. I would also ream the barrel bore back to just before the first port, as I don't think you would want the projectile engaged in rifling while passing the ports. The baffles I would plug weld to the tube, and give them an ID that slip fit over the barrel.

That's basically what I intend to do when I get to the integral can on my list.

[LostintheAOs]

As i said, it's only offset due to it originally being designed for a De Lisle Carbine clone. It'll be on a bolt gun only, by making it this way i'll also be able to swap it over to my 10/22 (that would have a barrel with the same porting) if I wanted to, or even onto my Marlin XT-22 or Savage 93. The barrel would be back bored so there would be no rifling for the bullet to engage.




Pretty much like this, though I think I'll have the muzzle threaded and have it thread on that way, with an o-ring set into the front flat of the barrel to seal against the inside of the end cap. By threading the cap on it would press the can against the shoulder on the barrel to hold it all in place.

[Kuraki]

Sounds like a plan. I like the idea of an endcap, rather than having to turn the entire tube on or off. Also solves any clocking issues for an eccentric.

The more I think of this idea the more I like it. With enough prior planning, you could build 1 can to cover a large number of calibers. 12 gauge to .22 depending on barrel diameters involved.

But, don't you run into the same issues as the SIG MPX "muzzle brake"? Does each ported barrel become "suppressor parts"?

[Capt. Link.]

This type of suppressor while attractive due to simplicity is not effective in center fire calibers.A chamber of less than 1.00 is not advised in .22 rimfire.I have made enhanced versions that are extremely quiet in .22 rimfire but when used with the 5.7x28 the suppressor is overwhelmed by pressure.A 300blk version would require at least 2.00" chambers using a minimum of 5 plus a expansion chamber if used on a gas operated rifle.A much better suppressor can be designed in terms of size and suppression if simple baffles are used.CL

Enhanced with cross flow ports. Built by CMV

[LostintheAOs]

I guess my only question now is what you mean by a chamber less than 1.00. Do you mean the size of the hole that's crossdrilled?

[Capt. Link.]

I guess my only question now is what you mean by a chamber less than 1.00. Do you mean the size of the hole that's crossdrilled?

Correct
These type of suppressors require volume to work as they do not strip gas from the stream nor do they create much turbulence.The enhanced version works a bit better but still needs volume for suppression.CL

[curtistactical]

This was the original ported 300Blk I done, I ended up adding 3 K baffles later on(second pic) and it ended up being the quietest 300Blk I have ever heard.[img][/img[IMG]http://i1285.photobucket.com/albums/a591/curtistactical09/DSCN5995_zpsf4a6a3cf.jpg[/img]]
[img][/img[IMG]http://i1285.photobucket.com/albums/a591/curtistactical09/DSCN6113_zps405948fd.jpg[/img]]

[LostintheAOs]

wouldn't the main shell of the can (as shown in the first post) have enough volume for what you are saying? the photo of the drilled barrel was just to show how the barrel itself would look.

[T-Rex]

wouldn't the main shell of the can (as shown in the first post) have enough volume for what you are saying? the photo of the drilled barrel was just to show how the barrel itself would look.

I am wondering this same thing.
I threw the following design together rather quickly just to show the same idea a bit differently.


White lines are the original barrel, 1" OD x 16"L.
Purple lines are the Tubing, 2" x .065, roughly 11" OAL.
Blue lines are the Tail and End caps,
-Tail piece is tight fit with set screw(s) and o-ring groove to tubing.
-End cap threads to the OD of barrel to press tubing against Tail piece.
-As drawn about .375-.5" thick
Yellow lines are a separator for the blast/reflex chamber to suppressor portion, forward of this the bore is opened up,
-Tight fit, silver soldered to barrel, o-ring groove to tubing.
-As drawn .25" thick
Green circles are muzzle brake/porting to blast area,
-As drawn .25" drill @ 60 degree array, 4 rows
Cyan lines are chamber dividers,
-Tight fit, silver soldered to barrel, o-ring groove to tubing.
-As drawn .1" thick spaced 1.15" between
Red circles are chamber holes w/ cross-flow ports
-As drawn .88" drill spaced .375" apart
-Cross-flow ports are drawn as .25" drill

The chamber separators, coupled w/ a 2" tube, would add considerable volume to the interior of the suppressor. The blast/reflex chamber seems like it bleed off a lot of the gas before it gets into the chambers. Maybe different sized or design porting would work better, this is just what I threw together quickly.

The OP used a 300BLK as his caliber for design. I've just drawn the design w/o caliber in mind. Obviously there is no gas port for semi-auto rifle.
What platform, if any, do you think this would benefit for? Something like 9mm or 45ACP?


I kinda liked the silver solder idea, but plug welding the separators isn't out of the question.

[LostintheAOs]

thanks for whipping up a CAD version, that's pretty much what I was envisioning. And if I get around to building a SMLE in 45acp I might just leave it concentric to the barrel.

[Capt. Link.]

Far better designs exist as curtistactical has demonstrated.The through hole baffles will not strip gas effectively nor will the baffle plates enhance turbulence.While volume is important doing something with it is just as important.

[T-Rex]

I understand what you are saying, its 100% beleivable.
What I don't understand is how curtitsactical's is so much more efficient. (I believe you that it is quiet)
It looks as though the gas can simply swim around those half baffles.
If they were closer I could understand your point, but his suppressor, while seemingly simple, just looks like volume volume volume.
The DeLisle uses the same principle of separated chambers with flat faces, albeit slightly angled.

What if the through holes, instead of a straight drill through, were made with a 3/16 drill around the same diameter? Would these ripples/teeth cause enough disruption?

What's your thought on the silver solder rather than plug welder to the tubing?

What's your thought in the break/porting? Would it be better with different holes, spacing or something like milled channels?

[curtistactical]

The original design of my suppressor with just the over barrel portion ran somewhere in the low 130db range with sub sonics which is very loud for sub sonic 300Blk, after I added the 3 K baffles to the end of it the db dropped under 120db. What Capt Link is saying is the over the barrel portion will strip some gas away but without creating a turbulent flow it will not strip enough gas away to make it quiet and he is 100% correct. What my final design did do was the over the barrel portion took enough gas and pressure off that it let the 3 K baffles ahead of the muzzle work exceptionally well. I suppose if you had enough over the barrel suppressor eventually all the gas would be taken care of but I don't know what that length would be, probably somewhere around 15". With the over barrel portion on mine the barrel was turned to .625" and the baffles were a slip fit over that. The barrel ports were .125" diameter and angled forward at 25 degrees. Each chamber sealed off so it only had one port flowing into each chamber. This was the first suppressor I ever built so I done a whole lot of learning on it, the integral Ar's I do now do not use this design as I have come up with way more efficient designs over the years just wanted to share my experience with you on what I had learned with this design since you were thinking of a similar design.

[LostintheAOs]

Sorry, been on leave and had to travel back home. I appreciate all the input, and I've come up with an idea in my head. I have duty on Wednesday, so I'll get it drawn up and I'll post it Thursday for some more constructive criticism. Thanks again for the help with the design.

ETA, curtistactical, do you have a picture of all the internals laid out?

[curtistactical]

Sorry, been on leave and had to travel back home. I appreciate all the input, and I've come up with an idea in my head. I have duty on Wednesday, so I'll get it drawn up and I'll post it Thursday for some more constructive criticism. Thanks again for the help with the design.

ETA, curtistactical, do you have a picture of all the internals laid out?

The pics above are all that I had backed up when my shop burnt down so I lost the pics of it with the 3 K baffles, I will see if I can find one with the baffles over the barrel.

[LostintheAOs]

Ok, round 2. I kept the original ported barrel design but merged the first 2 ports together. I also kept the "in-between port" baffles and made them all one assembly similar to how curtistactical made his. I added a threaded muzzle with what amounts the a screw on cup (think golf ball launcher) and 3 baffles. The baffles would stack onto the cup to maintain spacing. Now to figure out the best way too attach it all. FWIW I'd like to be able to completely disassemble it for cleaning, just because I can.

[curtistactical]

For attachment make a custom gas block that has threads on the OD for the tube to thread onto, I would pin the gas block in place and not just rely on set screws to hold it on. Then you can thread an end cap into the other end of the tube to hold everything in place.

[LostintheAOs]

Sorry, I just realized that I never mentioned that this is going onto a Bolt Action. Though I think that I can build it (per the above design) and have a shoulder on the barrel for one end cap to hold against and the cup that threads on the muzzle would lock it all together. Then the other end cap would hold the baffles against the cup. So basically the cup would be the only piece actually attached to the barrel, and everything else is held between it and the end caps.

ETA: I could also plug weld a retainer ring behind the cup to give it something solid to butt up against, instead of the ring insert

[curtistactical]

My bolt gun designs are totally different, I never go larger than 1.25" diameter but usually stay at 1", I like using length instead of diameter for volume on bolt guns. I would start out with a 6" barrel and use a full length tube that covers the whole barrel. If you turn the barrel to fit snug inside the tube that will align it for you, then just weld the tube on and have the muzzle end of the tube threaded for the end cap. By going with a 6" barrel you could have 10" of suppressor and just be to non sbr length. With 1" diameter 10" should be enough cone baffles for good suppression.

[LostintheAOs]

My bolt gun designs are totally different, I never go larger than 1.25" diameter but usually stay at 1", I like using length instead of diameter for volume on bolt guns. I would start out with a 6" barrel and use a full length tube that covers the whole barrel. If you turn the barrel to fit snug inside the tube that will align it for you, then just weld the tube on and have the muzzle end of the tube threaded for the end cap. By going with a 6" barrel you could have 10" of suppressor and just be to non sbr length. With 1" diameter 10" should be enough cone baffles for good suppression.

I'll keep that in mind during my builds, since I can just about guarantee I will be doing several of these. Do you think this design would work for a bolt gun, even down to a 1.5" OD?

[curtistactical]

My bolt gun designs are totally different, I never go larger than 1.25" diameter but usually stay at 1", I like using length instead of diameter for volume on bolt guns. I would start out with a 6" barrel and use a full length tube that covers the whole barrel. If you turn the barrel to fit snug inside the tube that will align it for you, then just weld the tube on and have the muzzle end of the tube threaded for the end cap. By going with a 6" barrel you could have 10" of suppressor and just be to non sbr length. With 1" diameter 10" should be enough cone baffles for good suppression.

I'll keep that in mind during my builds, since I can just about guarantee I will be doing several of these. Do you think this design would work for a bolt gun, even down to a 1.5" OD?

It would work but would be bulkier than necessary for an integral on a bolt gun. The AR platform is the only rifle I go to 1.5" OD on because it fits the profile of the gun and looks good, all of the other integrals I do I try to keep the OD as small as possible so it just looks like a bull barrel.

[clark4283]

My bolt gun designs are totally different, I never go larger than 1.25" diameter but usually stay at 1", I like using length instead of diameter for volume on bolt guns. I would start out with a 6" barrel and use a full length tube that covers the whole barrel. If you turn the barrel to fit snug inside the tube that will align it for you, then just weld the tube on and have the muzzle end of the tube threaded for the end cap. By going with a 6" barrel you could have 10" of suppressor and just be to non sbr length. With 1" diameter 10" should be enough cone baffles for good suppression.

What is the wall thickness of your tubing and how big is your blast chamber? I'm thinking of doing a integral on my savage.

[LostintheAOs]

I'll be using .065" Stainless for my 300BLK. I would imagine this size would work for most medium sized centerfire rifles. if you're suppressing a 22lr you might be able to get away with .035"

[clark4283]

I'm thinking of doing a 300 blk also. I'm still deciding if it's worth the time. I already have a .30 cal can.