pdsmith505
Member
- Joined
- Mar 9, 2013
- Messages
- 736
So, you’ve decided you want to build a silencer. GREAT! It’s a fun, rewarding project.
But, wait, you’re tool-poor. All you have is a few files, a drill press, and a compound vice.
I’m going to show that it can be done with the help of the various “solvent trap” manufacturers out there.
What is a solvent trap? Think of it as an 80% silencer. All the hard work is done for you… threading the tube, making the adapters, end caps, and the baffles. You want titanium? No problem! Need a booster for a pistol can? Yup, they make those too! Want to make a monocore? Radial baffles? Cones? K’s? No problem! If you can dream it, someone out there can make it to help you along your way. The key point that distinguishes a “solvent trap” from a silencer is that a bullet cannot pass through a trap. This means you will only be responsible for boring out the baffles and end cap (they come center-drilled already for you, how neat is that?).
I’ll leave finding the parts you want and the suppliers up to you, but http://form1suppressor.boards.net and the Silencers – Build it Yourself forum over at Arfcom are great resources.
Anywho, on to my shiny new pistol can. My Form 1 (you did submit an application to make a NFA Firearm, right?) calls for an 8” long, .45 caliber silencer.
I plan to use it for a variety of guns, from 9mm pistol all the way up to 5.56 rifle rounds. That rules out aluminum, as well as K baffles. Omegas are patented, so you can’t find them as almost finished parts. This leaves radial baffles and cones. Since this will primarily be for pistol-caliber rounds, I went with radials.
After getting in touch with my chosen supplier (Diversified Machine), I had a pile of parts in front of me. $370 worth of machined titanium, and one 17-4 stainless baffle. He had the parts in stock, so it only took 2 days from payment to delivery. Fantastic!
So, time to get dirty and drill some holes, right? Nope, not so fast! This guy needs to have all the appropriate information engraved before we start down the path of bullets going down the bore. There are several places you can send your tube off to for engraving, but I ended up choosing Tarheel State Firearms in North Carolina. Give them $30 and some instructions, and they will professionally laser engrave your information. They are an SOT, so you can send and receive firearms from them directly. Two days to ship it down there, one day to engrave, two to get back to me. Now that’s service!
Alright, now it’s time to get to work. But what exactly are we trying to do? Just drill holes? You can do that, and it works. But it works better if you “clip” the baffles as well. Essentially, a clip is a small cut taken from the nose of the baffle. It helps to introduce additional turbulence in the gasses. More turbulence = slower, cooler gas = quieter can. Based on the knowledge and experience of others, I chose to do what is known as a “dual hybrid clip”.
Alright, with a plan in mind, let’s get to work. First step is to drill out the baffles. 17-4 stainless and Grade 5 titanium are hard. REALLY HARD. You’ll want good, sharp drill bits turning fairly slowly and a whole lot of cutting oil. Don’t skimp out on the cutting oil and use WD-40 or some such non-sense. Then, start small and work your way up to the final drill. This is a .45 can, so my final bore will be 17/32” or .531”. That is the closest drill size to being 0.080” over the .458” diameter of a .45 ACP bullet.
Now that the bore is drilled (you did go ahead and drill all of the baffles right?), it’s time to start clipping. This will be a milling process with four operations and two tools: a square end mill and a ball nose end mill. PM me if you want detailed dimensions. Another option is to do them by hand with a dremel and some files. There are people who have success with this method, but I feel bad even using a drill press as a mill, so that was a no-go for me.
This is a good opportunity for some planning. Lets say your drill has a bit of runout (the bit wobbles) and you’ve got a couple of holes that aren’t centered in the baffle. Measure it out, mark the areas that have the minimum and maximum wall thickness. These are the areas to cut the clips out to mitigate the off-center bore. A couple of mine were out as much as .010”, with the best being about 0.003”. My drill has a lot of runout, and accurate holes are an art. If I had access to a mill and lathe, I would have used them, FOR SURE! If I was paying a machinist to do this, I'd have told him to try again.
Step one and two is cutting the shelfs with the square end mill. To do this, you have to set up the machine to make the right depth of cut. Set the drill stop with the mill touching the part, bring it back up, then adjust the stop for depth. I did several tests on a block of aluminum prior to cutting my baffles to make sure I was getting the right depth. You’ll also need to find the edge of the baffle with the tool to make the right width of cut. Sorry if it's hard to see everything going on there... I really needed 3 hands to do this AND take a picture.
Now, here’s the caveat to milling with a drill press. Drill presses don’t take side loads well, if at all. You’ll either wear out your bearings faster, or the chuck will come loose damaging your part. The solution is to plunge mill everything, then go back and make cleanup passes with your compound vice. Do one side, then repeat on the other.
Time for a tool change: we need the ball end mill to cut the scoops. Otherwise the process is the same as the shelves, except this time you need to find the center of the baffle, not the edge. Touching off on the inside diameter of the part, and counting turns to the other side will get you there (or close enough for the drill-press machinist).
Now it’s time to clean things up a bit. A round file and a flat safety file are your friends at this stage. Clean it up, de-burr, measure, adjust as necessary to make things even, and you’re good!
Rinse and repeat for the rest of the baffles.
Drilling out the end cap is similar to the baffles. Just don’t cut any clips! Put it all back together and you have yourself a shiny new can! I will likely throw the baffles in a lathe one of these days to clean up the bores, but for now, she's done.
To put a finish on, you can either find an SOT that does cerakote or paint it yourself. I've had fantastic results using VHT rattle-cans (BBQ paint won't hold up) from Autozone. Bonus of doing it yourself is you can always touch it up later.
I’m still waiting on my booster, so no sound comparisons, but that’s essentially all there is to it.
Without the booster, this one comes in a 9.6 oz. With the booster, I expect to still be well under a pound.
But, wait, you’re tool-poor. All you have is a few files, a drill press, and a compound vice.
I’m going to show that it can be done with the help of the various “solvent trap” manufacturers out there.
What is a solvent trap? Think of it as an 80% silencer. All the hard work is done for you… threading the tube, making the adapters, end caps, and the baffles. You want titanium? No problem! Need a booster for a pistol can? Yup, they make those too! Want to make a monocore? Radial baffles? Cones? K’s? No problem! If you can dream it, someone out there can make it to help you along your way. The key point that distinguishes a “solvent trap” from a silencer is that a bullet cannot pass through a trap. This means you will only be responsible for boring out the baffles and end cap (they come center-drilled already for you, how neat is that?).
I’ll leave finding the parts you want and the suppliers up to you, but http://form1suppressor.boards.net and the Silencers – Build it Yourself forum over at Arfcom are great resources.
Anywho, on to my shiny new pistol can. My Form 1 (you did submit an application to make a NFA Firearm, right?) calls for an 8” long, .45 caliber silencer.
I plan to use it for a variety of guns, from 9mm pistol all the way up to 5.56 rifle rounds. That rules out aluminum, as well as K baffles. Omegas are patented, so you can’t find them as almost finished parts. This leaves radial baffles and cones. Since this will primarily be for pistol-caliber rounds, I went with radials.
After getting in touch with my chosen supplier (Diversified Machine), I had a pile of parts in front of me. $370 worth of machined titanium, and one 17-4 stainless baffle. He had the parts in stock, so it only took 2 days from payment to delivery. Fantastic!
So, time to get dirty and drill some holes, right? Nope, not so fast! This guy needs to have all the appropriate information engraved before we start down the path of bullets going down the bore. There are several places you can send your tube off to for engraving, but I ended up choosing Tarheel State Firearms in North Carolina. Give them $30 and some instructions, and they will professionally laser engrave your information. They are an SOT, so you can send and receive firearms from them directly. Two days to ship it down there, one day to engrave, two to get back to me. Now that’s service!
Alright, now it’s time to get to work. But what exactly are we trying to do? Just drill holes? You can do that, and it works. But it works better if you “clip” the baffles as well. Essentially, a clip is a small cut taken from the nose of the baffle. It helps to introduce additional turbulence in the gasses. More turbulence = slower, cooler gas = quieter can. Based on the knowledge and experience of others, I chose to do what is known as a “dual hybrid clip”.
Alright, with a plan in mind, let’s get to work. First step is to drill out the baffles. 17-4 stainless and Grade 5 titanium are hard. REALLY HARD. You’ll want good, sharp drill bits turning fairly slowly and a whole lot of cutting oil. Don’t skimp out on the cutting oil and use WD-40 or some such non-sense. Then, start small and work your way up to the final drill. This is a .45 can, so my final bore will be 17/32” or .531”. That is the closest drill size to being 0.080” over the .458” diameter of a .45 ACP bullet.
Now that the bore is drilled (you did go ahead and drill all of the baffles right?), it’s time to start clipping. This will be a milling process with four operations and two tools: a square end mill and a ball nose end mill. PM me if you want detailed dimensions. Another option is to do them by hand with a dremel and some files. There are people who have success with this method, but I feel bad even using a drill press as a mill, so that was a no-go for me.
This is a good opportunity for some planning. Lets say your drill has a bit of runout (the bit wobbles) and you’ve got a couple of holes that aren’t centered in the baffle. Measure it out, mark the areas that have the minimum and maximum wall thickness. These are the areas to cut the clips out to mitigate the off-center bore. A couple of mine were out as much as .010”, with the best being about 0.003”. My drill has a lot of runout, and accurate holes are an art. If I had access to a mill and lathe, I would have used them, FOR SURE! If I was paying a machinist to do this, I'd have told him to try again.
Step one and two is cutting the shelfs with the square end mill. To do this, you have to set up the machine to make the right depth of cut. Set the drill stop with the mill touching the part, bring it back up, then adjust the stop for depth. I did several tests on a block of aluminum prior to cutting my baffles to make sure I was getting the right depth. You’ll also need to find the edge of the baffle with the tool to make the right width of cut. Sorry if it's hard to see everything going on there... I really needed 3 hands to do this AND take a picture.
Now, here’s the caveat to milling with a drill press. Drill presses don’t take side loads well, if at all. You’ll either wear out your bearings faster, or the chuck will come loose damaging your part. The solution is to plunge mill everything, then go back and make cleanup passes with your compound vice. Do one side, then repeat on the other.
Time for a tool change: we need the ball end mill to cut the scoops. Otherwise the process is the same as the shelves, except this time you need to find the center of the baffle, not the edge. Touching off on the inside diameter of the part, and counting turns to the other side will get you there (or close enough for the drill-press machinist).
Now it’s time to clean things up a bit. A round file and a flat safety file are your friends at this stage. Clean it up, de-burr, measure, adjust as necessary to make things even, and you’re good!
Rinse and repeat for the rest of the baffles.
Drilling out the end cap is similar to the baffles. Just don’t cut any clips! Put it all back together and you have yourself a shiny new can! I will likely throw the baffles in a lathe one of these days to clean up the bores, but for now, she's done.
To put a finish on, you can either find an SOT that does cerakote or paint it yourself. I've had fantastic results using VHT rattle-cans (BBQ paint won't hold up) from Autozone. Bonus of doing it yourself is you can always touch it up later.
I’m still waiting on my booster, so no sound comparisons, but that’s essentially all there is to it.
Without the booster, this one comes in a 9.6 oz. With the booster, I expect to still be well under a pound.
