a few questions??

Yes, it can be legal to make a silencer. For everything Form-1, from silencer designs that are easily made, to filing forms with the BATF, to 3D modeling. Remember, you must have an approved BATF Form-1 to make a silencer. All NFA laws apply.

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crazyelece
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a few questions??

Post by crazyelece » Mon Feb 25, 2013 1:00 am

Ok some background. I am not a machinist and only fool around in my spare time as a hobbiest. That said I do have a bridgeport and an engine lathe and a fair amount of experience on both. I told myself that when I got to a point where I could finish an AR15 0% forging and thread a barrel, that I would Form 1 a suppressor. Originally I was just going to make a nice simple .22lr can, but I already have a commercial one. So I am now thinking of doing a .17 hmr can. I already ordered my forms and hope they are delivered shortly.

So my questions:
1) is it safe to say that a .22lr can design done in stainless steel will be good for .17hmr (of course with a slightly smaller through bore)?

2) what would be the best internal design (monocore, k baffle, step cone, etc.)?

3) what would be some decent overall dimensions to shoot for (this will be going on a rifle shot mainly from the prone position off a bipod)?

4) does .17 hmr need to be user serviceable like .22lr, and if so what kind of cleaning cycle should I be looking at?

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Dr.K
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Re: a few questions??

Post by Dr.K » Mon Feb 25, 2013 1:38 am

Ill be putting a 22lr can soon, and i plan on using my swr Spectre as a guide. It is rated for hmr, and works beautifully on mine! Id go that route if i were you.

Use all stainless, and get permission if you use the omega baffles, they are patented.

Go to atf.gov and just download the form1. No need to wait on the mail.
Kyle O.

crazyelece
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Re: a few questions??

Post by crazyelece » Tue Mar 05, 2013 12:10 am

Well I think I have narrowed down the setup to either K baffles or step cones. Any opinions on which would be better for .17hmr? I have filled the forms out for 8" in length. The rifle is a bolt gun shot off a bipod. Hoping to start some drawings in the next few days!

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Bendersquint
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Re: a few questions??

Post by Bendersquint » Tue Mar 05, 2013 11:27 am

crazyelece wrote:Ok some background. I am not a machinist and only fool around in my spare time as a hobbiest. That said I do have a bridgeport and an engine lathe and a fair amount of experience on both. I told myself that when I got to a point where I could finish an AR15 0% forging and thread a barrel, that I would Form 1 a suppressor. Originally I was just going to make a nice simple .22lr can, but I already have a commercial one. So I am now thinking of doing a .17 hmr can. I already ordered my forms and hope they are delivered shortly.

So my questions:
1) is it safe to say that a .22lr can design done in stainless steel will be good for .17hmr (of course with a slightly smaller through bore)?

2) what would be the best internal design (monocore, k baffle, step cone, etc.)?

3) what would be some decent overall dimensions to shoot for (this will be going on a rifle shot mainly from the prone position off a bipod)?

4) :mrgreen: does .17 hmr need to be user serviceable like .22lr, and if so what kind of cleaning cycle should I be looking at?
Cant answer #1 until we know your design.

#2 is based on what you want as he dedicated caliber. Multi caliber suppressor are great they are jacks of all caliber and only the master of one. Which one that is for you inly you can decide.

#3 would be whatever size you want, larger does perform better to a degree. 1.25x7 would give you a sweet large volume can for the rimfire calibers.

#4 yes it needs to be cleaned just a little less than 22lr, most 17 i have seen were all jacketed or plated bullets but still uses crap powder

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Re: a few questions??

Post by DMY » Tue Mar 05, 2013 12:50 pm

Bendersquint wrote:
crazyelece wrote: 1) is it safe to say that a .22lr can design done in stainless steel will be good for .17hmr (of course with a slightly smaller through bore)?
Cant answer #1 until we know your design.
Can you give a little more info on this Bender? It seems like stainless is the go-to material for durability. What are some design characteristics that are not well suited to stainless, but instead better suited to other materials such as aluminum, etc?

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Re: a few questions??

Post by Bendersquint » Tue Mar 05, 2013 1:01 pm

DMY wrote:
Bendersquint wrote:
crazyelece wrote: 1) is it safe to say that a .22lr can design done in stainless steel will be good for .17hmr (of course with a slightly smaller through bore)?
Cant answer #1 until we know your design.
Can you give a little more info on this Bender? It seems like stainless is the go-to material for durability. What are some design characteristics that are not well suited to stainless, but instead better suited to other materials such as aluminum, etc?
SS is good for durability, I wasn't talking about material selection.

22lr is a pretty weak cartridge, a baffle design suited for 22lr may not handle the 17 cartridges without damage.

Its a Form1 build afterall so I assume it will weigh far more and be alot thicker than necessary. That will alleviate most of the potential issues.

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Re: a few questions??

Post by punkinhead » Tue Mar 05, 2013 1:22 pm

Bendersquint wrote:

Its a Form1 build afterall so I assume it will weigh far more and be alot thicker than necessary. That will alleviate most of the potential issues.
What would be a typical baffle wall thickness for a commercial. 22LR suppressor?

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Re: a few questions??

Post by crazyelece » Tue Mar 05, 2013 1:47 pm

A couple step cone designs I drew up today. 1"x8" outside dimensions, blast baffle .1 thick, all others .05 thick. Blast baffle is .1x.1 steps, others are .2x.1 steps. 1/2x28 thread on, 28 tpi on the end caps .94 on the major diameter. Excuse the left hand thread on the one end cap, I forgot to go back and fix it!! Oh yeah figuring on stainless.


Thoughts???

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rqlasl
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Re: a few questions??

Post by rqlasl » Wed Mar 06, 2013 7:26 pm

I have a thought. I'm thinking K

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Bendersquint
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Re: a few questions??

Post by Bendersquint » Wed Mar 06, 2013 7:29 pm

K is what you need to do.

Not sure the continued fascination with step cones, especially that variant of them.

crazyelece
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Re: a few questions??

Post by crazyelece » Wed Mar 06, 2013 8:13 pm

Bendersquint wrote:K is what you need to do.

Not sure the continued fascination with step cones, especially that variant of them.
Thank you - finaly an answer to my original #2 question. If this was given in the begining I wouldn't have wasted time drawing step cones. I decided to draw them up first because they seemed easier to draw.

I have also been reading a lot on the omega baffle. So another question - of the two (omega or k), which would be the better choice?

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Re: a few questions??

Post by doubloon » Wed Mar 06, 2013 8:34 pm

One design with plenty of dimensions. viewtopic.php?f=10&t=78483

Might find a few more with this search http://www.google.com/search?num=100&hl ... ertalk.com
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

crazyelece
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Re: a few questions??

Post by crazyelece » Thu Mar 07, 2013 12:17 am

yes, there is a ton of info out there for .22 but I'm interested in .17hmr and its just not discussed as much. All the info I'm finding is stuff like "my 22 can handles hmr pretty well" and while its good to know, I'm trying to find out what works best for the hmr. Although using google instead of the site search may provide better results, thanks for reminding me of that. More reading!!

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doubloon
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Re: a few questions??

Post by doubloon » Thu Mar 07, 2013 12:41 am

Yeah, the site search sucks.

http://www.silencertalk.com/forum3/view ... 08#p695708

Omega Baffle Zip file :arrow: http://www.dskarmory.com/files/st/Omega_Baffle.zip
sumkrnboy wrote:
Hatchetjoe wrote:sumkrnboy,
Any chance you can zip that file and post a link to that? I wouls like to add properties and look at this weigh myself. Part of it is that you made it @ 1.25" dia. I think the original Spectre is 1" dia, if memory serves me correctly.
SolidWorks Omega Baffle ZIP file.

Yes, the SWR Spectre has a 1" OD, but I was not trying to make a SWR Spectre clone.

You can run 17 HMR, 22LR, 22 Mag, 22WMR, 5.7x28, and light .223/5.56 loads through this can and is full auto rated.

If you have a SWR Spectre or a SilencerCo Sparrow suppressor, compare it with this design with 8 baffles once you have your form 1 approved.

Substitute the tubing with grade 9 titanium and use aluminum for the last few baffles if you wish to reduce the overall weight.
http://www.youtube.com/watch?v=BDtd2jNIwAU MUSAFAR!
http://www.youtube.com/watch?v=8CrOL-ydFMI This is Water DavidW
Complete Form 1s http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895

crazyelece
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Re: a few questions??

Post by crazyelece » Fri Mar 08, 2013 1:11 am

Well after a lot of reading it seems the most admired among the 17 hmr guys is the popularity with the Spectre and the omega baffle. So my next attempt was with omega baffles. Any tips or suggestions here?

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Bendersquint
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Re: a few questions??

Post by Bendersquint » Fri Mar 08, 2013 11:08 am

Way too many baffles.

Aside from that it looks basically like a Spectre1.

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Re: a few questions??

Post by Historian » Fri Mar 08, 2013 2:08 pm

Bendersquint wrote:Way too many baffles.

Aside from that it looks basically like a Spectre1.

Mr. B., I am baffled.

Over the years there have been a few critiques on the number
of baffles ... "Too many" ... "Not Enough". Is this judgement
based on technical calculations or simply experimentation and experience?

For example the ancient ones such as the PH and German WW II had a spate of
them. Meanwhile the 'French Silencer' that was an imitation of the PH, four or so disc baffles,
with spring separators; metering it in the Frankford Arsenal Test Report gave it the same DB range
as other .22 suppressor.

I have mentioned in a past post that a limited production .22 PH had no baffles, just a pipe sticking
out from the front end cap 3/4 of the way back. Reminiscent of the Hush Puppy without
the four sweeps in the tube.

I cannot recall this subject being discussed on this sit. Please point me to them if
they exist.


Best.

crazyelece
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Re: a few questions??

Post by crazyelece » Fri Mar 08, 2013 4:29 pm

Bendersquint wrote:Way too many baffles.

Aside from that it looks basically like a Spectre1.
Are you suggesting shorter overall length, or less baffles with more space between them?

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Re: a few questions??

Post by Bendersquint » Fri Mar 08, 2013 4:36 pm

crazyelece wrote:
Bendersquint wrote:Way too many baffles.

Aside from that it looks basically like a Spectre1.
Are you suggesting shorter overall length, or less baffles with more space between them?
Why don't you just copy the Spectre? The baffle size, spacing etc work, thats why SWR uses it! ;)

You are reinventing the wheel like a majority of the Form1 builders do and as such you may or may not have a good performing silencer.

Do you have permission to use the patented baffles? No sense wasting the time if you don't have the blessing to use them.

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Re: a few questions??

Post by crazyelece » Fri Mar 08, 2013 7:08 pm

Bendersquint wrote:
crazyelece wrote:
Bendersquint wrote:Way too many baffles.

Aside from that it looks basically like a Spectre1.
Are you suggesting shorter overall length, or less baffles with more space between them?
Why don't you just copy the Spectre? The baffle size, spacing etc work, thats why SWR uses it! ;)

You are reinventing the wheel like a majority of the Form1 builders do and as such you may or may not have a good performing silencer.

Do you have permission to use the patented baffles? No sense wasting the time if you don't have the blessing to use them.
Don't want to exact copy a .22 design. I know it works from the reports, but I'm looking to tune it for .17 hmr specifically.

Cars going down the highway don't use hand carved stone "wheels". It's not reinventing - its tuning, tweeking, improving. I don't have the luxury of being an 07/02 or living in a country free to experiment or I would and draw my own conclusions. I'm trying to draw off the experiences of the few here who can/ will share. I'd like to be steered away from anything that absolutely will be detromental to performance, steered toward things that are proven to perform, and suggestions on what may get a better result. For instance - I have 8" in overal length to play with, so which is likely to perform better - more of the "standard" size baffles, or spreading the same size baffles apart a little more, or maybe staggering the spacing similar to the big bore cans I've seen? It's ok to admit if you don't know, that's why I'm asking - I don't know. But if I wanted to blindly copy the Spectre I'd just go buy one.

No I have not yet asked for permission, but am assuming they do give it to form 1 builders as others have commented on it. I am still in the planning stage and until I have a design locked down I won't waste their time. I assume like many others they are in full "balls out" production mode.

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Re: a few questions??

Post by Dr.K » Fri Mar 08, 2013 7:33 pm

Like I said, and apparently a lot of others....the Spectre is badass on 17hmr! You will not be dissappointed.

If you wanna tweak it, then make the bore tighter, if it's crappy, then open it up some.
Kyle O.

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