300 Blk suppressor--Design turned into 5.56 can

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MatRussell122
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300 Blk suppressor--Design turned into 5.56 can

Post by MatRussell122 »

Thinking about building a suppressor and want to get some opinions on this design. Undecided on material but thinking 304 stainless because i have a bunch already.Image
Last edited by MatRussell122 on Mon Apr 17, 2017 9:11 am, edited 1 time in total.
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fishman
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Re: 300 Blk suppressor

Post by fishman »

The blast chamber doesn't need to be that big if it's gonna be dedicated to 300blk
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
MatRussell122
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Re: 300 Blk suppressor

Post by MatRussell122 »

What would you recommend for a blast baffle. This might see my 5.56 too but probably not often.
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Re: 300 Blk suppressor

Post by fishman »

MatRussell122 wrote:What would you recommend for a blast baffle. This might see my 5.56 too but probably not often.
17-4, inconnel, grade 5 titanium.
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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CMV
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Re: 300 Blk suppressor

Post by CMV »

What is baffle spacing? Those look WAY too close together for 30 cal. .600 - .700 neighborhood is a good place to be. .625 - .650 is good distance if 300BLK subs are your primary application.

Why the tiny port in side of cone? Is that all cones or just first? Regardless, I don't think you want that all. You want to make the gas follow the cone walls and deadend - not give it a shortcut to bypass the path you've laid out.

♫ 304 she's a whore ♪♪ .... Will work fine for your application. Nothing wrong with more exotic either.

Looks like you are welding? I'm lucky if I can mix JB Weld & get the right color so can't help there but wonder about the excess space at end. Also, if welding, you don't want the same internal clearance you would for a take-apart design. Can't tell from your drawing, but since you don't have to worry about removing dirty guts might as well get close to an interference fit. I'd also consider fully extending the cones and discarding the ridge at the end. Great design for integral spacer take apart but may as well run that cone wall up another ~.080. IF welding, otherwise disregard since I can't really tell what you're planning.

Blast chamber spacing is fine. Esp if you ever want good performance on other 30 cal applications. I like to jam K's right up to the muzzle (well relatively) but give a first cone some space.

Feel free to take whatever fits your application from here: viewtopic.php?f=10&t=136120 1.50 dia, 8" OAL - just don't get all jealous that my print is drafted sooo much better than yours :) :) :)
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Re: 300 Blk suppressor

Post by fishman »

Cmv, his spacing, clipping, and porting all seem to resemble the Sig silencers. Are they poor performers on 300Blk hosts?
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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Re: 300 Blk suppressor

Post by T-Rex »

fishman wrote:Cmv, his spacing, clipping, and porting all seem to resemble the Sig silencers. Are they poor performers on 300Blk hosts?
Clips should be aligned and baffles need more ports, but I agree; it resembles the Sig srd762ti
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CMV
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Re: 300 Blk suppressor

Post by CMV »

T-Rex wrote:
fishman wrote:Cmv, his spacing, clipping, and porting all seem to resemble the Sig silencers. Are they poor performers on 300Blk hosts?
Clips should be aligned and baffles need more ports, but I agree; it resembles the Sig srd762ti
No idea since I've never had one. I do know that for 1.5" OD, 8" OAL that looks like a whole lot more work & material than is necessary for 30 cal & 300BLK as primary host.
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Re: 300 Blk suppressor

Post by MatRussell122 »

Image

So rifle build went a different direction. this will be primarily a 5.56 can that will sometimes see a 308 and eventually ill build a blackout upper.

Made some changes to the design im also thinking ill weld the back suppressor cap and have the front of it thread off for cleaning. i have a .005 clearance on the baffles to the tube wall
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Re: 300 Blk suppressor

Post by fishman »

MatRussell122 wrote:Image

So rifle build went a different direction. this will be primarily a 5.56 can that will sometimes see a 308 and eventually ill build a blackout upper.

Made some changes to the design im also thinking ill weld the back suppressor cap and have the front of it thread off for cleaning. i have a .005 clearance on the baffles to the tube wall
Looks like a solid build. I personally would make the spacers and cones separate pieces. It will cut the amount of raw baffle material you need in half and you won't have to do nearly as much boring.
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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Re: 300 Blk suppressor

Post by CMV »

fishman wrote:
MatRussell122 wrote:Image

So rifle build went a different direction. this will be primarily a 5.56 can that will sometimes see a 308 and eventually ill build a blackout upper.

Made some changes to the design im also thinking ill weld the back suppressor cap and have the front of it thread off for cleaning. i have a .005 clearance on the baffles to the tube wall
Looks like a solid build. I personally would make the spacers and cones separate pieces. It will cut the amount of raw baffle material you need in half and you won't have to do nearly as much boring.
True. The benefit to what he has drawn is easier disassembly - esp since he will be fishing everything out from only one open end. I'd also increase clearance to .007"-.008" just due to that. Either way, looks like a good design for your hybrid .223/.308/.300BLK needs. The only thing I'd get more input on is baffle spacing since .223 is now primary host. I spaced mine evenly but I see a lot of guys here do variable spacing for their .223. Depends on which caliber you want best performance from.

I've done a few now with the .007" clearance and don't feel like performance has suffered from it. Seems like nothing - 2 thou isn't much - but enough to notice a difference getting the guts out.
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Re: 300 Blk suppressor

Post by MatRussell122 »

Image

Latest revision trying to get the weight down. also might drop 1 baffle to shorten it up a little. its a 10.5 upper so dont want to get too long.

Anyone with baffle suggestions?
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Re: 300 Blk suppressor

Post by fishman »

You do not want that blast spacer made of aluminum, you also probably shouldn't cut holes or slots in it.
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
MatRussell122
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Re: 300 Blk suppressor

Post by MatRussell122 »

Image

Removed a couple baffles to reduce length and changed materials a little bit. Now thinking about making the barrel sit inside the blast chamber a couple inches to keep it even shorter. if i do that i would make the blast chamber longer to make up for the area the barrel is filling. Thoughts on that?


Thanks again for the wealth of knowledge!
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Re: 300 Blk suppressor

Post by MatRussell122 »

Image

Something like this if it isnt a step backwards. this design is 24 oz
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by T-Rex »

Personally, I think you should make a 5.56mm suppressor, for 5.56mm. Don't build a 30cal suppressor that will primarily be used on 5.56mm. Tax stamps are relatively cheap (albeit pointless) and you've stated you have a bunch of SS so cost is minimal. When you're ready to make a 30cal suppressor, it can be for both HV and SS ammunition.

I've posted this before. It's a 1.5" x 6.25", 5.56mm design. All 17-4 and comes in at 17.6oz. Fully welded and baffles can also be ported.

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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by MatRussell122 »

Image

Is this a little better. i know its all pretty similar i just want to get it all ironed out now so i dont have to worry about it later.

now a designated 5.56 can
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Re: 300 Blk suppressor

Post by hammerdown12 »

fishman wrote:You do not want that blast spacer made of aluminum, you also probably shouldn't cut holes or slots in it.
he is 100% correct on both counts. A blast chamber spacer should be either steel or titanium. and you dont want the slots, that is just exposing your tube. The idea is a fairly well sealed baffle / spacer stack that does not allow any (or minimal at least) blast / carbon contact with the inner tube wall.

Id go with titanium to save weight, as at 21 oz you dont want any more weight.

diversified sells precut Ti spacers... reasonably priced too that should fit the bill nicely. especially if you dont have the proper equipment to cut Ti. Its a little more difficult to work with. Worth it though, IMHO.

http://diversifiedmachine.us/product/spacers/
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by T-Rex »

Since you have the ability to weld, you can forego the spacers and drop some weight right there.
Same as the front cap. No need for threads as a 5.56mm silencer does not need to be serviced.
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by MatRussell122 »

Image

Weight it 22.5 oz
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by T-Rex »

Try it w/ an OD of 1.5in and see what the weight is.
1.5 x 6-7in is a popular 5.56mm silencer size so no reason you shouldn't be able to follow suit.
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by MatRussell122 »

Image

18 ounces.

dropped to 1.5 OD and shortened .5 inch.

Also changed end cap to make up for losing a baffle. (not sure if this is a step forward or back?)
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by T-Rex »

You don't necessarily need a profiled end cap, especially since you have 8 baffles.
The enlarged volume of the last chamber (by having a flat cap) can help decrease exit gas pressure.
I'd change the baffle clip, a bit. Do an image search and look at commercial designs.
Adding some ports, to the first couple baffles, can help eliminate increased back-pressure.
It looks good, though. 18oz is more like it :)
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by MatRussell122 »

Image
Image

Think this is my final revision. please review and give green light the design.
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Re: 300 Blk suppressor--Design turned into 5.56 can

Post by hammerdown12 »

I see no advantage to porting that last baffle. You can port the first 3 to reduce blowback, but porting that last one does nothing. Also, it's up in the air by many on how advantagous clipping the baffles are. On my Octane 45, they are all clipped. I'm betting silencerco knows what they are doing. That said, either clip them all or don't clip any. I wouldnt mix and match clipped and non clipped baffles like that. I think all that will do is cause more poi shift. FWIW, I don't clip my rifle can baffles. I would on a pistol can though. Clipping them on a rifle can won't hurt though. I think the benefit is somewhat lost on high pressure cans.

Other than that, looks good. What size is blast chamber? 1.3-1.5 is considered optimal by most folks.
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