material selection assistance

[vz58]

I have had the stamps on hand for a while but life has been in the way. Plus my band new 6 jaw chuck has come in (needs mounting but hey its here)

The rifles the suppressor will need to go on:
SBR 6.5" BlackOut Ar15 Mostly supersonic, some subsonic.
20" 6.5 Grendal AR15
SBR 12.5" 308 AR10
18" 308 AR10
And periodically 5.56 AR15

The Stamp:
max of 10.75" (longer than I plan)




Construction:
Blast baffle: Iconel

The cones: What grade stainless? Or should I go Titanium? If titanium what grade? I have never cut titanium, but I have heard from a machinist buddy its a bitch and you have to turn and burn it. I have also read the opposite.

The tube:
Diameter 1.625 outside.
Materiel: Stainless but what grade? Where to buy?

The tools:
Logan 12" lathe converted to CNC
4 axis mill converted to CNC


Bender, if I go titanium tips on turning

[Bendersquint]

You know my suggestion is titanium.

Grade9 for tubing and Grade5 for baffles.

[vz58]

You know my suggestion is titanium.

Grade9 for tubing and Grade5 for baffles.

Yes but you have experience cutting it. I dont...

[SRM]

316 or 17-4 for stainless.

[ChimeraPrecision]

Inconel will be hell to cut.

If you have heat treat capabilities 17-4.

For ease of machining go 303/304

Extra strength could go 316

[DMY]

If you have heat treat capabilities 17-4.

Just want to throw this out there - I was looking at some info on heat treated 17-4. I am thinking H900 or so is the only way to go. From what I can tell, H1150 has about the same properties as Condition A (untreated.) See here:

http://www.aksteel.com/pdf/markets_prod ... lletin.pdf

Extra strength could go 316

I understand that 316 readily work hardens when machining, and can therefore be more difficult to machine. Is 17-4 the same way? I don't know much about the martensitic stainless steels (like 17-4) WRT work hardening.

[vz58]

I have a kiln but have never used it.. I theoretically have heat treat capability. But will not count on it.

[Bendersquint]

If you have heat treat capabilities 17-4.

Just want to throw this out there - I was looking at some info on heat treated 17-4. I am thinking H900 or so is the only way to go. From what I can tell, H1150 has about the same properties as Condition A (untreated.) See here:

http://www.aksteel.com/pdf/markets_prod ... lletin.pdf

Extra strength could go 316

I understand that 316 readily work hardens when machining, and can therefore be more difficult to machine. Is 17-4 the same way? I don't know much about the martensitic stainless steels (like 17-4) WRT work hardening.

17-4 work hardens really fast! Sometimes is can catch you like

[DMY]

17-4 work hardens really fast! Sometimes is can catch you like

Bummer! Is it as bad as the austenitic grades?

BTW, McMaster-Carr sells H900 and I think H1150 17-4 round bar. You'll have to cut it in it's hardened state, but that's not the end of the world.

[ChimeraPrecision]

17-4 work hardens really fast! Sometimes is can catch you like

Bummer! Is it as bad as the austenitic grades?

BTW, McMaster-Carr sells H900 and I think H1150 17-4 round bar. You'll have to cut it in it's hardened state, but that's not the end of the world.

IMHO don't cut harrened Stock. It's a pain in the ass. I've cut hard material and it is never a pleasurable experience.

304 is my favorite. I don't heat treat but I can produce top notch machined products.

[57fairlane]

Whatever materials you pick, post up some pictures after that 12.5" .308 gives it hell.

You will find out exactly how strong your mount, spacer, baffle, material selection is on that rifle

[Fulmen]

I understand that 316 readily work hardens when machining

316L (weldable) seems to be more common than regular 316, I believe L is worse when it comes to work hardening. It's not a huge deal if you're aware of that and act accordingly, but if unaware you can get into trouble really fast.

[Shift1]

I use 316L pretty often, actually building a .308 can right now using this material for the internal components. The only issue I am currently having machining it at the moment, is trying to part the stuff off. My machine is smallish and does not do all that well with Carbide tooling.....speeds and feeds are too slow. Will at some point find the happy medium to make it all work out. Have three more baffle slugs to part off a piece of bar stock, then some spacers from tubing. This is number three using 316L for the internals.