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.
daviscustom wrote: ↑Fri Jun 21, 2019 8:26 am
It isn’t very thin wall tube. It is 2mm wall I believe.... 1.34ish ID and 1.57ish O.D.
I am planning on the tube OD shrinking down in between the threads, but I still want to keep the larger O.D. as small as possible since 1.5” is really a little big for my brand new Trijicon suppressor height sights...... which I think are one of the tallest options without going to a red dot sight.
That's extremely thick, especially for pistol cartridges. It's gonna be heavy. I'd save that thick, expensive tube for a magnum rifle can.
If you revisited this with .035" wall 1.375" OD tube, you'd only give up .035" on your ID while keeping OD down to pistol can size and shaving a ton of weight.
For the record, my 9mm model is 1.25" OD .035" wall, 8" overall length.
Not intending to leave it thick. It was a way to get Grade 5 tube and have material to make the I.D. and OD the size I wanted. Planning to bore to 1.375” and turn it down thin everywhere except where I need extra material for the threaded joints. Was planning to make the shorter extended section of tube with the same ID, so it would appear that I would need the tube to be thicker where they screw together.
.... So back to the question at hand. With a 1 7/16”-28 ID threaded grade 5 tube how much additional unthreaded material thickness would you feel comfortable with if you were trying to make it as small as possible?.... then I guess part B of the same question....is .035” final tube thickness overkill? I plan to turn down the O.D. as small as possible in all areas, only leaving thickness where it is needed for threaded joints and material strength. I may go to a 36 or 40 thread pitch for the joints in the tube and the front cap just to keep it smaller.
Maybe I made a mistake making the cap with that size thread on the O.D. I thought 1.5” finished size was reasonable and it gave me some room for a coaxial chamber in the blast chamber.
The myopic majority will be our republic's undoing.
daviscustom wrote: ↑Fri Jun 21, 2019 4:17 pm
.... So back to the question at hand. With a 1 7/16”-28 ID threaded grade 5 tube how much additional unthreaded material thickness would you feel comfortable with if you were trying to make it as small as possible?
.015" from thread root/undercut to OD would be plenty for me with gr. 9 CWSR. Gr. 5 is stronger still even in the annealed state.
I built one .45 pistol prototype with .023" wall CWSR tube, got so thin in the roots you could actually see the thread profile on the outside of the tube. It held up for several hundred rounds before finally cracking at the undercut. It was only .004" thick.
Do be aware that seamless Ti tube is heavily stressed from manufacturing, likes to distort when you start boring or turning down OD. Even using a sleeve or mandrel, all you do is guarantee wall thickness; the stuff will oblong as soon as you set it free, and it's very difficult to squish/beat it into a round shape again. When I dogbone my Valkyrie model, it's the last step before engraving & moly resin. The core is permanently installed & keeps the tube round.
daviscustom wrote: ↑Fri Jun 21, 2019 4:17 pm
.... So back to the question at hand. With a 1 7/16”-28 ID threaded grade 5 tube how much additional unthreaded material thickness would you feel comfortable with if you were trying to make it as small as possible?
Do be aware that seamless Ti tube is heavily stressed from manufacturing, likes to distort when you start boring or turning down OD. Even using a sleeve or mandrel, all you do is guarantee wall thickness; the stuff will oblong as soon as you set it free, and it's very difficult to squish/beat it into a round shape again. When I dogbone my Valkyrie model, it's the last step before engraving & moly resin. The core is permanently installed & keeps the tube round.
Oh crap, you have mentioned the distortion issue before and I will have to admit that had slipped my mind. Now you have me a little worried. I guess with a centerfire can, cleaning shouldn’t really be a big issue. My idea was to turn between centers after it was finished and assembled..... but I was planning to be able to take it apart, especially the modular front end..... hmmm
Is that something you usually notice when it gets really thin?... just wondering if I left .04 on the main part of the tube if that might not go crazy?
Have you experimented with material removal on the O.D. such as milling patterns to remove weight? Any luck keeping the tube round with that sort of approach?
Hopefully close to the final baffle design. Trying to make the skirt port a little small but easily enlarged with a needle file.
In regards to the tube, I am going to try to use what I have and just rough profile the OD first so if it goes out of round I can bore the ID last and hopefully get it round. If that doesn’t work I will have to scrap the tube and do something different. I want to be able to remove the baffles, so if I have to buy more material so be it.
...... which I think are one of the tallest options without going to a red dot sight.
...... which I think are one of the tallest options without going to a red dot sight.
