plz DELETE
- Thread starter Svt40 fan
- Start date
How are you boring these brakes once installed?
If the brake is made in one operation in the lathe, the bore and threads will be concentric as the workpiece never gets unchucked. Then once the bore of barrel is dialed in, and barrel threaded, there is no way for brake and bore to be out, unless you’ve got a taper in your lathe? Are you using a reamer when your “boring” the brake out when it’s mounted? How do you keep it on axis with bore?
Always appreciate new ideas.
QUOTE=guntech;14999321]You don't just need your barrel threaded, you need the brake bored after it is installed... and it's b r a k e not break.[/QUOTE]
If the brake is made in one operation in the lathe, the bore and threads will be concentric as the workpiece never gets unchucked. Then once the bore of barrel is dialed in, and barrel threaded, there is no way for brake and bore to be out, unless you’ve got a taper in your lathe? Are you using a reamer when your “boring” the brake out when it’s mounted? How do you keep it on axis with bore?
Always appreciate new ideas.
QUOTE=guntech;14999321]You don't just need your barrel threaded, you need the brake bored after it is installed... and it's b r a k e not break.[/QUOTE]
I set up through the head stock ... the muzzle end of the barrel in a 4 jaw chuck and dial the bore in to the closest I can using a 10 thou indicator... the other end of the barrel is in a 4 jaw spider and I dial that end in to about a thou or two ... that end just needs to be close.
With the barrel held this way I machine the threads and fit the brake, indexing it as required. When that is done, I usually install the brake with blue Loctite. While the barrel is still set up and the brake now installed, I bore the brake out to 20 or 25 thou over bullet diameter. That's about a precise as it gets and the brake will operate with the most efficiency and accuracy.
Last edited:
- Location
- Nova Scotia
I had Richard AKA Triaiq do a couple.
Thanks for the pic. I’m still confused how that will fit down a 7mm hole, 2” in depth to meet the face of the barrel to true up the bore of the muzzle brake.
I’m missing something here.
I’m missing something here.
Home made boring bar, 12 inches in length, takes 3/16" square 'bits', fit 1 inch holder or 5/8 inch holder.
Isn't it H S S not HHS? Lol just had to.
I use the same technique as guntech, with a different style of tool. Picked up a handful of them at an auction. Imagine a drill bit with a single, slow flute. Sharpen by grinding the end. Hold in the tool post, run in with a slight angle to the brake bore, to give clearance for the tool and chips.
With the barrel properly set up in the lathe, the threads for the brake will be concentric with the bore. I prefer unfinished brakes with starting hole only, and bore them to suit the caliber.
If the thing is a finished commercial one, then boring to guarantee coaxial alignment isn't possible. Thread the barrel carefully and assume that the brake manufacturer did a good job. If the bullet doesn't strike the brake, then I suppose installation is a success.
Have a look at the bore diameters of different finished brakes. Some are guaranteed not to have alignment issues or bullet strike problems no matter how the barrel threads are cut. A 3/8" bore and a .224" bullet aren't going to make contact.
With the barrel properly set up in the lathe, the threads for the brake will be concentric with the bore. I prefer unfinished brakes with starting hole only, and bore them to suit the caliber.
If the thing is a finished commercial one, then boring to guarantee coaxial alignment isn't possible. Thread the barrel carefully and assume that the brake manufacturer did a good job. If the bullet doesn't strike the brake, then I suppose installation is a success.
Have a look at the bore diameters of different finished brakes. Some are guaranteed not to have alignment issues or bullet strike problems no matter how the barrel threads are cut. A 3/8" bore and a .224" bullet aren't going to make contact.
Last edited:
So that kind of sounds like an end mill with one flute then? Not a bore bar. And you run it in till you contact the face of the barrel?
I’ve never seen a brake of appropriate caliber have projectile contact, that to me is a catastrophic mistake.
I’ve never seen a brake of appropriate caliber have projectile contact, that to me is a catastrophic mistake.
