This is with very little tools. You can use a 7/32" drill bit, belt sander/grinder, electric drill, punch, and hammer for members who are doing a direct thread on suppressor. Members who are going with a muzzle device attachment might want to get a 7/32" drill rod from Brownells that is 18" long, so the rod is long enough to stay centered in the barrel bore, to get a center dimple. The 7/32" drill/rod is for AR's with 5.56/.223. Members with other calibers will need to use the correct size rods for there rifles. http://www.brownells.com/gunsmith-tools-supplies/small-hardware/metal-stock/water-hardening-drill-rod-prod585.aspx

After you receive your solvent trap tube, thread protector, and end cap.

Take the 7/32" drill or rod and chuck it up in the drill. Those using a drill bit, chuck it up with the drill backwards. Now using the electric drill and belt sander/grinder, put the drill bit or rod at a angle while the drill and sander/grinder is running. This will make a centered point on the tip.







Take the freeze plug and give it a light scuff across some fine sandpaper, I used 400 grit. This will give you a clean smooth finish to see the light dimple later.



Now using only your AR upper, only install the thread protector and tube. You do not use the end cap at all for this. Also remove the BCG and CH. Assemble the thread protector and tube to the barrel. Slide in a freeze plug with the sanded side facing the barrel bore. Use something to push and hold in the freeze plug tight against the bottom of the thread protector. I used the handle of a hammer. Now stand everything up on end, and drop the drill bit (pointed end down) down the  barrel to create a centered dimple on the freeze plug. Now you have a centered dimple that matched really close to you barrel bore. For demo purpose, the 3rd pic was just showing the drill bit being dropped.

A light dimple will show on the freeze plug, so use a sharpened punch in the small dimple to make it larger for drilling the bore thru the freeze plug.




To show how centered you can get this, I used my lathe to make a slug for demo purpose. Notice the first pic with no dimple, but the center milling marks left by the lathe. Second pic is after I dropped the drill bit down the barrel with the above method. Notice the second pic puts the dimple in the center where the lathe left milling marks.

So simple it's genius. Nice work.

Thanks. Its also cheap/free. I made the drill rod up at work, but forgot to bring it home. The drill rod should produce a deeper dimple, because of the heavier weight.

I remembered to bring home the pointed 7/32" drill rod. First pic shows the demo slug machined on the lathe, notice no dimple, but machine marks and glare showing center of slug. This slug is make out of MP35n, way harder than any freeze plug. Last 2 pics shows the dimple hits center.

A transfer punch could be used instead of a sharped drill bit.

I love stuff like this...

I'll be stamping my tube. To help keep the stamping die and letters/numbers in a even row, I took 80SCH pvc pipe and slotted it on a table saw. Then used 2 hose clamps to tighten the pvc around the tube. Now I'll be able to place the stamping die sides against the pvc to maintain the numbers/letters in a even row. Last pic was a test piece.

genius.  That is really cool.

What calibers would this work with? Assuming different size calibers, if there is any play with the drill bit, wouldn't it be off slightly? And possibly cause a baffle strike?

First post states this was for 5.56/.223, when used with a 7/32" drill/rod/transfer punch, will be .2188". When trying this on other calibers, you need to find the closes drill/rod/transfer punch available. Example, .308 would use a "N" drill (.302"). You will have to figure out what drill/rod/transfer punch to use for your caliber. You can get drills/rods/transfer punches in variety of OD sizes, either in decimal or metric.

Some of those center jigs you buy on-line I've seen, show .010" +/- tolerance. This can put your center out by .010" +/-, not to mention the operater drilling, drill flex, and 60* forming can throw hole off center.