First form 1 build, critique my plans please

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bna5017
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First form 1 build, critique my plans please

Post by bna5017 » Tue Dec 24, 2019 6:39 pm

Preparing to send in a form 1 shortly, this will be mainly used on a 6.5 creedmoor and may see occasional use on a 300 win mag, which is the reason for the tube thickness.

Tube is 1.5" x .095" 304SS. According to my model current weight is 1.5 pounds, which includes the weight of the blast chamber spacer that is not shown in the attached image.

Looking for some opinions on the overall design and suggestions on baffle spacing, weight reduction etc..

http://cubeupload.com/im/bna5017/suppdesign.jpg

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Re: First form 1 build, critique my plans please

Post by T-Rex » Tue Dec 24, 2019 7:43 pm

You're going to want something a bit bigger, especially for 300WM. It'll be best suited closer to 1.75x10.
What is the distance from muzzle brake to first baffle tip?
What is your plan for clipping?
Your tubing is seamless?
.095 will be thicker than needed, after about the second baffle. I'd use a lathe to step taper, maybe twice.

There's zero need to service this type of suppressor. You could lighten the spacers, or not use any and plug weld the baffles, and weld the end caps.
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Re: First form 1 build, critique my plans please

Post by bna5017 » Tue Dec 24, 2019 9:56 pm

T-Rex wrote:
Tue Dec 24, 2019 7:43 pm
You're going to want something a bit bigger, especially for 300WM. It'll be best suited closer to 1.75x10.
What is the distance from muzzle brake to first baffle tip?
What is your plan for clipping?
Your tubing is seamless?
.095 will be thicker than needed, after about the second baffle. I'd use a lathe to step taper, maybe twice.

There's zero need to service this type of suppressor. You could lighten the spacers, or not use any and plug weld the baffles, and weld the end caps.
I plan on building a dedicated can for magnum calibers after this one is complete, so I'm trying to focus this one on non magnum 30 and under calibers at the moment. I also intend to build a rimfire can shortly after this one. At the moment this one is designed to handle a 300 win mag at its maximum capacity, but I don't think there's any likelihood that it will ever see any use on it. I just don't shoot that rifle much, it's more of an elk hunting rig than anything else.

The distance from the end of the brake to the first baffle tip is 3/8". Too close? Too far?

I am open to suggestions on best clipping method. It seems like DHC is most popular/effective?

Yes, this will be seamless tubing. I have considered stepping the ID as well and will see what that weight reduction looks like.

While I have access to a variety of welders, none of them are TIG. And I am not proficient enough with TIG welding to be completely comfortable welding this up. I'd really like to stay with a threaded design. How are guys cleaning sealed cans?

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Re: First form 1 build, critique my plans please

Post by ECCO Machine » Wed Dec 25, 2019 2:44 am

T-Rex wrote:
Tue Dec 24, 2019 7:43 pm
You're going to want something a bit bigger, especially for 300WM. It'll be best suited closer to 1.75x10.
1.5 x 8" can be made to work pretty well on cartridges in that class. But it's not going to be forgiving, so a new F1 builder really should opt for a bit more volume to compensate for not having the luxury of refining a minimalist design.

I will echo that .095 is overly thick, all you're doing is hurting internal volume and making it a pig. The 1.5" x 8" cans I build hover right around 1 pound finished weight, and that includes 100% stainless critters. I just did a 1.5" x 10" recore build that came in at 18.7 oz (20.4 with the Griffin Plan A installed). Granted, that was a tubeless one, but it's all 17-4. There are ways to keep all-steel cans fairly light, but heavy walled 304 tube isn't one of them. You should really reconsider your tube.

Building for a 300 WM in a conventional F1 design with cones & spacers or serviceable skirted cones, I would recommend the Diversified Machine ASR Advantage in 9"-10" length. A good sized blast chamber and 10-12 progressively spaced conical baffles in that critter will perform well.
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Re: First form 1 build, critique my plans please

Post by bna5017 » Wed Dec 25, 2019 9:31 am

ECCO Machine wrote:
Wed Dec 25, 2019 2:44 am
T-Rex wrote:
Tue Dec 24, 2019 7:43 pm
You're going to want something a bit bigger, especially for 300WM. It'll be best suited closer to 1.75x10.
1.5 x 8" can be made to work pretty well on cartridges in that class. But it's not going to be forgiving, so a new F1 builder really should opt for a bit more volume to compensate for not having the luxury of refining a minimalist design.

I will echo that .095 is overly thick, all you're doing is hurting internal volume and making it a pig. The 1.5" x 8" cans I build hover right around 1 pound finished weight, and that includes 100% stainless critters. I just did a 1.5" x 10" recore build that came in at 18.7 oz (20.4 with the Griffin Plan A installed). Granted, that was a tubeless one, but it's all 17-4. There are ways to keep all-steel cans fairly light, but heavy walled 304 tube isn't one of them. You should really reconsider your tube.

Building for a 300 WM in a conventional F1 design with cones & spacers or serviceable skirted cones, I would recommend the Diversified Machine ASR Advantage in 9"-10" length. A good sized blast chamber and 10-12 progressively spaced conical baffles in that critter will perform well.
I don't think I am going to end up using this on my 300WM at this point. I'll probably build another one down the road for that rifle.

What do you recommend for wall thickness on a 1.5" tube for a non magnum 30 caliber? I ran through the calculations and it looks like I need a minimum of .073" wall for a 6.5 creedmoor with a 16" barrel and a 2.5 cubic inch blast chamber?

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Re: First form 1 build, critique my plans please

Post by bna5017 » Thu Dec 26, 2019 12:02 pm

I made some revisions to my design, reduced tube wall thickness (. 050") with intent to use 17-4 stainless tubing, added dhc clips to all baffles, and stepped down baffle spacing towards end of the tube. Current weight is now 1.3 lbs. I'm curious to hear what everyone thinks about how this will perform?

http://u.cubeupload.com/bna5017/dhcsupp.jpg

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Re: First form 1 build, critique my plans please

Post by #40Fan » Thu Dec 26, 2019 1:57 pm

Image

You're going to bore out a piece of 17-4 round bar to make a tube?

titaniumjoe.com for some tubing.

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Re: First form 1 build, critique my plans please

Post by bna5017 » Thu Dec 26, 2019 4:29 pm

#40Fan wrote:
Thu Dec 26, 2019 1:57 pm
Image

You're going to bore out a piece of 17-4 round bar to make a tube?

titaniumjoe.com for some tubing.
I was not planning on it, I have a call in with a material supplier who is working on a quote for 17-4 tubing for me. I would rather use titanium, but had not come across a decent source yet. That looks like a good place to start! Thank you!

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Re: First form 1 build, critique my plans please

Post by #40Fan » Thu Dec 26, 2019 8:46 pm

I had never searched for 17-4 tubing, but a quick google looks like it is available. Didn't click on anything to check pricing or availability though. Let us know what you find out.

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Re: First form 1 build, critique my plans please

Post by ECCO Machine » Fri Dec 27, 2019 12:08 am

bna5017 wrote:
Thu Dec 26, 2019 4:29 pm


I was not planning on it, I have a call in with a material supplier who is working on a quote for 17-4 tubing for me. I would rather use titanium, but had not come across a decent source yet. That looks like a good place to start! Thank you!
They're gonna come back with a price you won't want to pay for a quantity you don't need. 17-4 tubing is not generally available, requires $pecial mill run$.

Tiger titanium supplies most of the solvent trap companies. That's where I buy CWSR tube.
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Re: First form 1 build, critique my plans please

Post by bna5017 » Fri Dec 27, 2019 8:13 am

Thanks guys. I've changed the tube to .054" wall grade 9 titanium. Anything jump out at you as far as the general design goes that you think I should be concerned about?

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Re: First form 1 build, critique my plans please

Post by T-Rex » Fri Dec 27, 2019 9:50 am

File your form 1, now, and design while you wait.
Are your making the brake and mount?
If so, a good option would be to put the taper lock ahead of the threads. Helps keep carbon out of them.
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Re: First form 1 build, critique my plans please

Post by ECCO Machine » Fri Dec 27, 2019 12:21 pm

bna5017 wrote:
Fri Dec 27, 2019 8:13 am
Thanks guys. I've changed the tube to .054" wall grade 9 titanium. Anything jump out at you as far as the general design goes that you think I should be concerned about?
Since you're making all your own parts, a couple things do, but first:

What length and diameter did you settle on?
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Re: First form 1 build, critique my plans please

Post by bna5017 » Fri Dec 27, 2019 2:43 pm

I am hoping to stick with 1.5" x 8" at this point. I am a little concerned about the tubing wall thickness around the threaded section of the tube.. If I thread it to 1.4375-24 there is only going to be about .030" of Wall thickness remaining, which is pretty thin for the amount of pressure I'm figuring the blast chamber will see. Also not real confident that I can thread that successfully without having a lot of distortion from the chuck clamping force..

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Re: First form 1 build, critique my plans please

Post by bna5017 » Fri Dec 27, 2019 2:45 pm

T-Rex wrote:
Fri Dec 27, 2019 9:50 am
File your form 1, now, and design while you wait.
Are your making the brake and mount?
If so, a good option would be to put the taper lock ahead of the threads. Helps keep carbon out of them.
Yes, I am planning to make the brake and mount, but I would like to have the option to buy a brake/mount off the shelf if I get lazy and don't want to make one for any new rifles that I may acquire.

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Re: First form 1 build, critique my plans please

Post by ECCO Machine » Fri Dec 27, 2019 4:45 pm

bna5017 wrote:
Fri Dec 27, 2019 2:43 pm
I am hoping to stick with 1.5" x 8" at this point. I am a little concerned about the tubing wall thickness around the threaded section of the tube.. If I thread it to 1.4375-24 there is only going to be about .030" of Wall thickness remaining, which is pretty thin for the amount of pressure I'm figuring the blast chamber will see. Also not real confident that I can thread that successfully without having a lot of distortion from the chuck clamping force..
That's plenty. I have run 300 Win Mag and full auto .308 through cans using .035" wall CWSR tubing with 36 pitch threads and just .018" WT in the undercut.

I would, however, suggest 28 pitch threads for .054" wall tube. That way you can counterbore them slightly for ease of installing & removing internals without sacrificing engagement or getting thinner on the root & undercut WT. 1-7/16 28 will have a 1.400" minor on the tighter side of 3B spec.

For 1.5" x 8, your baffle count is alright. I generally put nine of them in a tube that size. In my R&D, I found 50° cones superior to 60° for high pressure supersonic cartridges, and use a single radiused clip. Again, manufacturing them yourself, you're not constrained by market availability, so you can do that, as well as put indexing features on them so you're not stuck using the DHC to minimize bullet disruption. The DHC simply does not work as well to curb laminar flow; in my experience, DHCd baffles will be louder, all else being equal.
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Re: First form 1 build, critique my plans please

Post by fishman » Fri Dec 27, 2019 6:30 pm

The griffin taper attachment system is easy to machine on your own. You can make your own brakes, buy them from griffin, or a mix of the two.
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: First form 1 build, critique my plans please

Post by bna5017 » Fri Dec 27, 2019 11:08 pm

ECCO Machine wrote:
Fri Dec 27, 2019 4:45 pm
bna5017 wrote:
Fri Dec 27, 2019 2:43 pm
I am hoping to stick with 1.5" x 8" at this point. I am a little concerned about the tubing wall thickness around the threaded section of the tube.. If I thread it to 1.4375-24 there is only going to be about .030" of Wall thickness remaining, which is pretty thin for the amount of pressure I'm figuring the blast chamber will see. Also not real confident that I can thread that successfully without having a lot of distortion from the chuck clamping force..
That's plenty. I have run 300 Win Mag and full auto .308 through cans using .035" wall CWSR tubing with 36 pitch threads and just .018" WT in the undercut.

I would, however, suggest 28 pitch threads for .054" wall tube. That way you can counterbore them slightly for ease of installing & removing internals without sacrificing engagement or getting thinner on the root & undercut WT. 1-7/16 28 will have a 1.400" minor on the tighter side of 3B spec.

For 1.5" x 8, your baffle count is alright. I generally put nine of them in a tube that size. In my R&D, I found 50° cones superior to 60° for high pressure supersonic cartridges, and use a single radiused clip. Again, manufacturing them yourself, you're not constrained by market availability, so you can do that, as well as put indexing features on them so you're not stuck using the DHC to minimize bullet disruption. The DHC simply does not work as well to curb laminar flow; in my experience, DHCd baffles will be louder, all else being equal.
I was planning on going with 1.4375-28 threads on the tube and end caps. I was planning on doing dhc clips, but if regular radius clips are better I'd rather do that as it'll be a bit easier to machine. Thanks for the insight, I appreciate it!

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Re: First form 1 build, critique my plans please

Post by bna5017 » Fri Dec 27, 2019 11:10 pm

fishman wrote:
Fri Dec 27, 2019 6:30 pm
The griffin taper attachment system is easy to machine on your own. You can make your own brakes, buy them from griffin, or a mix of the two.
My thoughts as well!

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Re: First form 1 build, critique my plans please

Post by bna5017 » Sat Dec 28, 2019 12:43 am

What is the general consensus on clipping blast baffles? I've read a ton of conflicting opinions on whether it should be done or not.. This is going on a long range rifle, so accuracy is of high priority.

Is there any specific dimensions that seem to perform better than others for clips?

Also, does anyone use area 419's mount system? I already have hellfire brake and that system seems to be pretty robust, but I haven't seen anything about them in all the research I've been doing..

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Re: First form 1 build, critique my plans please

Post by ECCO Machine » Sat Dec 28, 2019 11:52 am

fishman wrote:
Fri Dec 27, 2019 6:30 pm
The griffin taper attachment system is easy to machine on your own. You can make your own brakes, buy them from griffin, or a mix of the two.
On that note, the print that is often posted for those is wrong. The 1"-20 threads are correct, but that's it. The correct included taper is 16°, and the threads are further forward.
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Re: First form 1 build, critique my plans please

Post by ECCO Machine » Sat Dec 28, 2019 11:55 am

bna5017 wrote:
Sat Dec 28, 2019 12:43 am
What is the general consensus on clipping blast baffles? I've read a ton of conflicting opinions on whether it should be done or not.. This is going on a long range rifle, so accuracy is of high priority.

Is there any specific dimensions that seem to perform better than others for clips?

Also, does anyone use area 419's mount system? I already have hellfire brake and that system seems to be pretty robust, but I haven't seen anything about them in all the research I've been doing..
Always clip all baffles.

As for the Area 419 system, it's a really good PRS mount, a fair number of the Omega conversion I do end up running those with good results. But the Hellfire mount adapter is not a brake, so it won't do anything to reduce erosion of a blast baffle.
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Re: First form 1 build, critique my plans please

Post by bna5017 » Sat Dec 28, 2019 2:03 pm

ECCO Machine wrote:
Sat Dec 28, 2019 11:55 am
bna5017 wrote:
Sat Dec 28, 2019 12:43 am
What is the general consensus on clipping blast baffles? I've read a ton of conflicting opinions on whether it should be done or not.. This is going on a long range rifle, so accuracy is of high priority.

Is there any specific dimensions that seem to perform better than others for clips?

Also, does anyone use area 419's mount system? I already have hellfire brake and that system seems to be pretty robust, but I haven't seen anything about them in all the research I've been doing..
Always clip all baffles.

As for the Area 419 system, it's a really good PRS mount, a fair number of the Omega conversion I do end up running those with good results. But the Hellfire mount adapter is not a brake, so it won't do anything to reduce erosion of a blast baffle.
Sounds like I best just buy one and have it on hand.

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Re: First form 1 build, critique my plans please

Post by bna5017 » Thu Jan 09, 2020 8:53 pm

Does anyone know of a source for information on the thunder beast cb mount dimensions? I'm considering going that route as it appears to have a steeper taper which I think will be more consistent when removing and reinstalling a suppressor on it. I believe a more shallow taper would likely allow for a greater amount rotation variation when threading a suppressor on, unless you were able to torque it the same amount every time you installed it.

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Re: First form 1 build, critique my plans please

Post by whiterussian1974 » Sat Jan 11, 2020 7:31 pm

bna5017 wrote:
Tue Dec 24, 2019 9:56 pm
T-Rex wrote:
Tue Dec 24, 2019 7:43 pm
What is the distance from muzzle brake to first baffle tip?
The distance from the end of the brake to the first baffle tip is 3/8". Too close? Too far?
I didn't see an answer to this, so I'd add my $.02 and say that I'd have the 1st baffle nearly kiss the brake. This would create a semi-enclosed blast chamber and also limit throat erosion on your blast baffle. Especially if the opening is just under the OD of your brake.

Also, why is your final baffle so far from your endcap? That is your lowest pressure Region. So you should have the MOST spacing there, not have it encroach upon the neighboring baffle.

You could also machine a cone on you endcap for the exit. Just a small .25" or so. I've seen many Builders include that.It helps with pressure retention, and also "smooths" the escaping gasses to increase Duration and thereby lessen Amplitude of the Atmospheric Disruption at Discharge.

Hope this helps. :D
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