Tube materials for rifle-caliber monocore

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hangman
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Tube materials for rifle-caliber monocore

Post by hangman »

I'm working on a new silencer design and considering a monocore construction in 17-4 PH stainless (I know, a little old-school, but there are some reasons that we can all discuss in a future thread). As I finish up my design drawings, I'm hoping for some expert opinions on tube materials.

Size: ~1.5" OD, could go to 1.625"; under 5" long. (again, I know, not going to be very quiet, but there are reasons that I'll share in a future thread)
Caliber: small bore centerfire rifle (.22-.30), but a little overbored to be capable of handling some pistol calibers (likely 0.41" to cover 9mm)
Velocity: supersonic capable, but subsonic intended
Rate: semi-auto generally, slower fire / bolt-action for supersonic

Or put another way, for an AR shooting 5.56/300 BLK/subsonic-458 SOCOM at the range / home defense, but safe for typical hunting use / calibers (like .308 WIN)

I read (about a dozen times) all of the posts in Suppressor Build Question topic https://www.silencertalk.com/forum/view ... 49#p977949 which helped clarify my thinking, but I think there are some differences considering the monocore design. Then again, the blast chamber is "sort of" an initial/single monocore "baffle"... having the same interaction between gas and external tube that is worrying me on design choices...

As I see it - there are 3 basic options, with my thoughts on pros//cons:
1) Aluminum (likely 7075) - light, cheap // probably should be thicker (maybe 0.1"??) at blast chamber if supporting much .308 or above at all
2) Titanium (perhaps in 3AL-2.5V) - light, can be thinner // expensive, and fear of it "wearing" with higher heat/gas-volume rounds
3) Stainless Steel (maybe 316?) - cheap, and whether accurate or not - I don't fear it "wearing" // heavy

Any input from the experienced experts? (and thanks in advance!)
Semper exaudiō,
HangMan
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Enfield577
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Re: Tube materials for rifle-caliber monocore

Post by Enfield577 »

Don't know if this helps and its not a monocore but I have a good quality can here for 308, made from an Aluminium alloy (cant find what), this is the blast chamber section and wall thickness measures to be 0.100".....I buy and fit a lot of these cans so know they are good quality and well designed.

Cheers

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hangman
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Location: Colorado, USA

Re: Tube materials for rifle-caliber monocore

Post by hangman »

Enfield577 -
This definitely helps. Especially considering I'm still prototyping - it looks like I'm not thinking completely unreasonably!
Enfield577 wrote: Thu Sep 14, 2023 5:32 pm Don't know if this helps and its not a monocore but I have a good quality can here for 308, made from an Aluminium alloy (cant find what), this is the blast chamber section and wall thickness measures to be 0.100".....I buy and fit a lot of these cans so know they are good quality and well designed.

Cheers
Great picture - though I do have a couple of follow-up questions.
1) Is that "diffuser" (the silver colored part with twisting ports) connected to the baffle stack?
1-b) If not, how is it attached / what keeps it concentric?
1-c) Is that component stainless steel?

2) Can you share a pic of the attachment device / adapter? (I'm curious because of the way it extends beyond the tube-threads to see how it all fits to the barrel - unless I've got it backwards and this is the "exit" of the blast chamber)

Thanks mate!
Semper exaudiō,
HangMan
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Enfield577
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Re: Tube materials for rifle-caliber monocore

Post by Enfield577 »

hangman wrote: Mon Sep 18, 2023 10:51 am Enfield577 -
This definitely helps. Especially considering I'm still prototyping - it looks like I'm not thinking completely unreasonably!
Enfield577 wrote: Thu Sep 14, 2023 5:32 pm Don't know if this helps and its not a monocore but I have a good quality can here for 308, made from an Aluminium alloy (cant find what), this is the blast chamber section and wall thickness measures to be 0.100".....I buy and fit a lot of these cans so know they are good quality and well designed.

Cheers
Great picture - though I do have a couple of follow-up questions.
1) Is that "diffuser" (the silver colored part with twisting ports) connected to the baffle stack?
1-b) If not, how is it attached / what keeps it concentric?
1-c) Is that component stainless steel?

2) Can you share a pic of the attachment device / adapter? (I'm curious because of the way it extends beyond the tube-threads to see how it all fits to the barrel - unless I've got it backwards and this is the "exit" of the blast chamber)

Thanks mate!
Hi,
The diffuser (built in brake) is built into the rear section of the can, the baffle stack screws on to that, it is stainless and appears pressed into the rear l/alloy anodized section. If you do a search on the web of Nielsen Danish suppressors, there is all sorts of details available. On NZ supplier "Delta Mike even has a fair bit of info on their site.

The barrel screws in from the rear of this (you can just about see the threads in the photo, the stainless parts goes back inside creating a rear reflex chamber. Hope this helps
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hangman
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Location: Colorado, USA

Re: Tube materials for rifle-caliber monocore

Post by hangman »

Helps immensely! Thanks again
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mr fixit
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Re: Tube materials for rifle-caliber monocore

Post by mr fixit »

I've built a handful of cans. I'm not worried about Titanium wearing, I think it is a forever can material. I would be concerned with aluminum. Don't forget the option of 4140/4130 steel construction, as light as stainless and stronger too.

At this point in my building, I'm more about light weight. Nothing like having a sweet rifle build and then hang a brick on the end to make you say 'no more'.

If possible and where reasonable I am leaning to all titanium in the future.
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