First Build of a Form 1

[kbillet]

Hello All, Ive been reading back thru a lot of the smithing post. Having purchased a Form 4 suppressor that has excessive run out has pushed me to deciding to make my own. The above would be for a bolt action, 22-250 with a 24" barrel, Looking for accuracy in that the use is to shoot prairie dogs out to 600 yds. I have a full machine shop at my disposal. The cans would be Grade 9 tube with the balance being Grade 5 or 17-4 PH. As drawn, the top sketch has a blast tube wall of .082. The blast baffle is .08 and the of baffles are .06. Tube is .087. Baffles three thru 9 have 4 radial holes. The lower sketch: Outer tube, .07, Blast tube .065, Blast baffle .08, balance of baffles .05 Sizes are partly determined by available material sizes. Intent is for all to be of welded construction. Sketches were drawn and modified over a period of time so my train of thought wasn't the same while drawing. Thoughts on modifications appreciated. The goal is for several individuals to be able to set up benches over a dog town and enjoy conversation and not damage out ears.
PS: Just received approval yesterday for my 4 Form 1's

[Capt. Link.]

Hello All, Ive been reading back thru a lot of the smithing post. Having purchased a Form 4 suppressor that has excessive run out has pushed me to deciding to make my own. The above would be for a bolt action, 22-250 with a 24" barrel, Looking for accuracy in that the use is to shoot prairie dogs out to 600 yds. I have a full machine shop at my disposal. The cans would be Grade 9 tube with the balance being Grade 5 or 17-4 PH. As drawn, the top sketch has a blast tube wall of .082. The blast baffle is .08 and the of baffles are .06. Tube is .087. Baffles three thru 9 have 4 radial holes. The lower sketch: Outer tube, .07, Blast tube .065, Blast baffle .08, balance of baffles .05 Sizes are partly determined by available material sizes. Intent is for all to be of welded construction. Sketches were drawn and modified over a period of time so my train of thought wasn't the same while drawing. Thoughts on modifications appreciated. The goal is for several individuals to be able to set up benches over a dog town and enjoy conversation and not damage out ears.
PS: Just received approval yesterday for my 4 Form 1's

Nice artwork! I love the 22-250 its a real screamer.While I've never suppressed a varmint rifle you should still use hearing protection as the sonic boom will toast your ears.The heat coming off a suppressor will cause mirage as well.That said suppressor construction built from 17-4 with the blast baffle made from inconel or at least 17-4ph-900 would be advised.This suppressor is going to get hot hot hot. If you weld the core a outer titanium tube can be used but need not be very thick as its just a sleeve.Keep it symmetrical.
-CL

[kbillet]

Thanks Capt. After reviewing 30 pages of smithing, you were one of individuals I was hoping to get input from. Thanks for you thoughts.

[kbillet]

Thought I would add a third option. Outer Tube .070, Blast Baffle & Blast Tube Spacer .080. The rest of the Baffles are .05.
I'm hoping to get some feedback as to which would work best for my 22-250 application. Still overall 1.5 by 8 inches. Possible alternative on the front cap. Suggestions appreciated.

[kbillet]

At this time I plan to move forward with the last drawing. To me it looks like the cleanest. I did reduce the wall thickness of the baffles(not Blast) to .05. This will give me a total weight of approximately 15 oz. Now to purchase material and get on with the build. Will let you know how it works out.

[kbillet]

Can't get my pictures to show up.

[kbillet]

Not sure why I am having so much trouble with copy and paste. At Any rate above are the parts I have made so far.Left is the Mount, 2nd is a 17-4 Step Blast Cone, next a 17-4 cone with .080 walls, next is standard Cone and last the Cap. I added the Step Cone to my original design and am going with threaded rather than welded assembly. Mounts still need threaded for the guns. I wasn't comfortable welding with the setup that I currently have. Need to finish the Blast Spacer and Thread the tubes. Everything is Titanium except the two mentioned items.
I started a Trust and put two of my old buddies it it. Now making three identical suppressors so we can enjoy our prairie dog hunts.

[daviscustom]

Why not thread your mount for the barrel before parting it off? That would have simplified maintaining concentricity.

[kbillet]

Plan is to thread the tube, assemble and than thread the mount as an assembly. Don't know if that is the best way but I kind of had that concept in my head from when I was thinking of welding.

[jnjproto]

If you chuck on the very end of the tube, with a slug to keep from distorting it, then steady rest the other end to thread tube you should be able to maintain concetricity. All threading on the end caps should be done in the same setup to eliminate any runout. What I would do in your case is thread a piece of stock that your caps will thread into. Do not remove it from the chuck, then screw in the caps and then thread them. This will guarantee concentricity and parallelism in the threads. I haven't made a suppressor yet, but have been machining for forty years. Hope this is of some help, good luck.
K
Ps. I shoot a 22-243 with an SWR 300 mag omega can, you'll love it on the 22-250.

[kbillet]

As built.

[daPhoosa]

Looks great!

What did the weight come to?

[whiterussian1974]

I know that I'm late to the party. But, you could drill holes in the M-baffle sidewalls to save weight. Whereas I WOULDN'T have done so in the blast chamber. (Your plan shows slits, but I don't see it in your completed pieces.)

Also, after 1000rds please let us know if the holes in your rear endcap fill w carbon. DrK said that he experienced this problem w some of his builds. Of course, you can always remove the web material if that b/c a problem.

And certainly, great and beautiful build. I'm jealous.

[T-Rex]

Very nice. Yes, please, report to us your results.

Tell me the model name is "Caliper"

[kbillet]

Final weight is 15.83 oz.
Whiterussiam, I'm not sure where you see the slits, unless the section lines look like slits.
I guess I should have just thined the blast spacer rather than cut the thru pockets.
T-Rex, You have to understand this was my first application for a Form 1 build. The govt. site for e-file is not the most user friendly. I have read that you didn't need to list a user model but I kept having the site indicate that there were errors in my application. This without defining what the problem was. So I kept trying different things until it accepted my form. It finally did and I now have three Form 1's that list the caliper as "22" and the model as "22 Caliper". So I hope my engraving meets the form.
As far as performance, I'm not sure at this time. I fired two shots with this suppressor and 2 using a SAS Arbitor 7.62 that I have. There is definitely a difference in tone but I couldn't tell as far as actually loudness. The Arbitor was more of a bass noise. It is 1.5" by 9". So it has more volume but I was hoping my .280 dia. bore vs .360 bore would have a noticeable improvement. I was using a 223, shooting 75gn A-Max bullets at 2940 FPS in a 22 inch barrel. I was under roof at the range. I think it would make a better comparison out in the open with multiple witnesses.
If I would put bleed/weep holes (as shown in the first cross section above) would that help with suppression? I've spent a lot of hours trying to digest post on this forum. Part of the problem for me is, it appears most of the builds are for SBR's,Pistols, high capacity mag dumps and Subsonic s. My interest is long range shooting and hunting. So weight is a factor, precision is a factor but all shots are with A-bolts and 20 to 24" barrels. Ultimately I want to build for 7MM WSM, 308 sub and super and some day for a 338 Lupra. I appreciate any and all suggestions.

[whiterussian1974]

Whiterussiam, I'm not sure where you see the slits, ...
I guess I should have just thined the blast spacer rather than cut the thru pockets.

I now have three Form 1's that list the caliper as "22" and the model as "22 Caliper". So I hope my engraving meets the form.

If I would put bleed/weep holes (as shown in the first cross section above) would that help with suppression? I've spent a lot of hours trying to digest post on this forum. Part of the problem for me is, it appears most of the builds are for SBR's,Pistols, high capacity mag dumps and Subsonic s. My interest is long range shooting and hunting. So weight is a factor, precision is a factor but all shots are with A-bolts and 20 to 24" barrels. Ultimately I want to build for 7MM WSM, 308 sub and super and some day for a 338 Lupra. I appreciate any and all suggestions.

A: Your 3rd sentence answers your 2nd. The Through-slits in the Blast Baffle.
Yes. I would have thinned instead of cutting "pockets." That would mean that the inner spacer would absorb most of the thermal stresses and slow outer tube heating. This way, You are exposing small areas to extreme heat/pressure.
As a test, I might even add a HSS coil spring inside the Blast Chamber and smear it w Li grease. It creates more exposed area to quench remaining fire and speed cooling exhaust gases. But many here don't like that option. Though it's similar to the perforated muzzle device some builders use.
B: The word is "caliber", no p. That's why he teased you. If "22 Caliper" is your model name, I'd add a decimal in front to meet marking reqs.
C: I don't think adding skirt porting (the proper name) would help performance. Since your 1st priority is accuracy, you've already got a solid can. Unless you are disappointed w performance, I wouldn't tinker w it.
If anything, you could notch the last 4 cone mouths. This would induce turbulance in chambers that the bullet has passed b/f being pressurized.

[kbillet]

I feel like an idiot. I'm a Toolmaker by trade. A caliper is something I have used often. Guess my left brain was moving faster than my right, or is that vice versa.

[whiterussian1974]

I feel like an idiot. I'm a Toolmaker by trade. A caliper is something I have used often. Guess my left brain was moving faster than my right, or is that vice versa.

Don't feel bad. Our brains see what we expect to see, rather than what is actually there.

[kbillet]

Thankfully because the letters were Bold Capital letters I could repair the idiots work.

Thanks T-Rex and Whiterussian for pointing that out and allowing for a correction.
On another note I went to the range today. There were two other guys there and I ask them to listen to the two different suppressors. My Form1 and the SAS 7.62 Ti Arbitor. I fired 5 rounds thru both. Their strong opinion was my Form1 was quieter. There is definately a difference in sound. They described mine as sounding like a 22 where as the SAS sounded more like a big gun. The crack of the sound barrier is not as evident with the SAS. I'm guessing the sonic crack is the main noise from my Form1. With the SAS other noises cover, to a degree, the sonic crack. But my 1.5" by 8" has a .271 bore. The SAS 1.5" by 9" has a .360 bore. At any rate I am pleased and thank everyone for their help.

[silencer_kid]

Thankfully because the letters were Bold Capital letters I could repair the idiots work.

did the person doing the engraving have a document to go by, or did s/he simply use a P instead of a B ?

[whiterussian1974]

Thankfully because the letters were Bold Capital letters I could repair the idiots work.

did the person doing the engraving have a document to go by, or did s/he simply use a P instead of a B ?

He was humbly deprecating himself. The Form1 itself stated "22 Caliper" as the model #. He stated that earlier in the thread.

So I kept trying different things until it accepted my form. It finally did and I now have three Form 1's that list the caliper as "22" and the model as "22 Caliper".

[kbillet]

silencer_kid. the s/he was me.

[silencer_kid]

silencer_kid. the s/he was me.

hah. well in that case, sorry you got caliper and caliber wrong. the caps were your lucky day, other than just making a new sleeve.

[whiterussian1974]

the caps were your lucky day, other than just making a new sleeve.

Which is illegal.
He could have filled in the engraved section and engraved on another section of the can.

[silencer_kid]

the caps were your lucky day, other than just making a new sleeve.

Which is illegal.
He could have filled in the engraved section and engraved on another section of the can.

illegal, how so, please explain. at the point of the engraving device stopping for the day the F1 can is still in the making, and will not be completed until the maker deems it complete. at that point the can with a "P" was not complete, and he started up the engraver the next day/week/year to finish engraving the "P" to a "B". absolutely nothing illegal about it. he could actually engrave more stuff next year if he wants, 100% legal. or, could have decided the tube was garbage, crushed it, started a new tube, then engraved that one correctly, because the 1st one, still in the making, had a machining flaw that deemed it not suitable for use.

get real.