HUB COMPATIBILITY
An open thread, so your silencer isn’t hostage to your mount.
HUB stands for Hybrid Universal Base. It’s a 1.375×24 thread at the back of a silencer — 1.375 inches across, 24 threads to the inch — and it isn’t any one company’s property. A silencer with a HUB base takes any HUB mount, from anyone.
We design to it rather than around it, which is a choice worth explaining. We’re Polite Society Industries, and every centerfire silencer in our line uses the open standard instead of a thread of our own. This page is what a mount actually does, why the industry spent twenty years making that hard, and what to look for if you’re buying one from somebody else.
First, what a mount is
A silencer has to attach to a firearm, and there are only two ways it happens.
Direct thread. The silencer screws straight onto the threads at the end of your barrel. Nothing in between. The silencer’s own rear threads match the muzzle threads, and that’s the entire system.
A mount. A separate component sits between the two. The mount attaches to the barrel — usually threading onto the muzzle, sometimes over a muzzle device — and the silencer attaches to the mount. Two interfaces instead of one, in exchange for being able to move the silencer between rifles quickly.
Which one a silencer uses is decided by the threads at its rear — the end nearest the shooter. A direct-thread silencer has barrel threads cut there. A mount-capable silencer has a larger, standard thread that accepts an adapter.
Which silencers use mounts
Broadly, small ones don’t and larger ones do.
A rimfire silencer is often direct thread only. It’s short, it’s light, it usually lives on one host, and a mount would add length and weight to something whose whole argument is that you stop noticing it.
Centerfire rifle silencers almost always take mounts, for the opposite reason. They’re bigger, they cost more, and the owner typically has several rifles to put one on. Being able to move it in seconds is worth the extra interface.
Ours split cleanly along that line. Temperance .22 is direct thread only — at four inches and three ounces, a mount would add length and weight to the one silencer whose entire argument is that you stop noticing it. Everything else takes a HUB mount: the Fortitude 5.56 in titanium or Inconel, the Verdict 7.62 the same two ways, and the Huckleberry, which takes two mounts because it’s built to follow you across calibers.
What HUB stands for
HUB is short for Hybrid Universal Base.
It’s a 1.375×24 thread at the rear of the silencer — 1.375 inches in diameter, 24 threads per inch — and it’s an open industry standard rather than any one company’s property. Every centerfire silencer in our lineup has one.
A silencer with a HUB base accepts any HUB-compatible mount. Direct thread adapters, quick-detach systems, brakes, flash hiders — from us or from anyone else who builds to the standard. The silencer stops being the thing that dictates your hardware.
The problem it solves
For most of the modern silencer era, the mount was the trap.
Every manufacturer had its own rear thread and its own family of muzzle devices. Buy a silencer and you bought into a system — the brakes, the adapters, the flash hiders, all from one company, none of it interchangeable with anything else. Change brands later and the hardware on every one of your rifles became scrap.
That wasn’t an accident. A proprietary mount is a very effective way to make sure a customer’s second silencer is the same brand as their first.
Where the standard came from
Nobody legislated 1.375×24. It became the standard the way most useful standards do — enough manufacturers adopted the same rear thread that it stopped being any one company’s idea and started being the thing everyone builds to.
That’s worth understanding, because it means HUB is not a feature we invented and it’s not a feature we can take away. It’s a dimension. A silencer either has it or it doesn’t, and ours do.
What a mount actually has to do
It looks like a simple part. It has three jobs, and all three are harder than they appear.
Locate the silencer concentric to the bore. The bullet passes through the middle of the silencer with a few thousandths of an inch to spare — and in ours, through three gas paths formed as a single piece of metal, which is a harder thing to keep concentric than a stack of cones. The mount is what decides whether the middle of the silencer is actually where the bullet is going.
Hold it there under recoil and heat. Every shot tries to shake the silencer loose and every string heats the interface. A mount has to stay tight across a temperature range that would loosen an ordinary threaded joint.
Survive the cycling. Threads that go on and off hundreds of times, at temperature, with carbon building up on them, are threads that wear. That’s why the mount that ships with ours is hardened 17-4 stainless rather than the same metal as the silencer — the mount is the part designed to absorb that wear instead of the silencer.
Get any of the three wrong and the failure doesn’t show up as a loose mount. It shows up as a mark inside the bore.
Which of ours use it
| SILENCER | BASE | SHIPS WITH |
|---|---|---|
| FORTITUDE 5.56 Ti / HD | 1.375×24 Hybrid Universal | 1/2×28 HUB Mounted Brake™ |
| VERDICT 7.62 Ti / HD | 1.375×24 Hybrid Universal | 5/8×24 HUB Mounted Brake™ |
| HUCKLEBERRY | 1.375×24 Hybrid Universal | 1/2×28 and 5/8×24 HUB Mounted Brake™ |
| TEMPERANCE .22 | Hollow Expansion Chamber | 1/2×28 direct thread |
Why we didn’t build our own
We could have. A proprietary mount is good business — it makes leaving expensive.
We’d rather you were able to leave. A silencer you can move between hosts, on hardware you already own, from whoever makes the mount you prefer, is simply a better thing to own. It’s the same reasoning behind what we charge for them. If the reason you buy your second one from us is that your first one worked, that’s the only reason we want.
Judging a third-party mount
If you’re buying a mount from someone else, four things are worth looking at.
Concentricity. The whole job of the mount is centering the silencer on the bore. A cheap mount is cheap because that tolerance was where the money got saved.
How it indexes. Does it seat against a shoulder, a taper, or nothing in particular? A mount that locates on a defined surface returns to the same place. A mount that simply tightens until it stops does not.
Material and thread quality. The interface runs hot and cycles often. Soft threads gall, and galled threads don’t come apart.
Whether tolerances stack. Every joint in the assembly carries a small error, and errors add. Barrel threads, muzzle device, mount, silencer — four interfaces, four chances to be slightly off true. It’s the same reason ours are formed as one continuous piece rather than assembled from a dozen. Fewer parts between the bore and the silencer is always the safer arrangement.
One caution
Building to an open standard means we don’t control what gets threaded into it. A HUB mount from another manufacturer is that manufacturer’s tolerances and that manufacturer’s alignment, not ours.
Our guarantee covers our hardware and our workmanship — including a mount of ours that stops holding zero. What it doesn’t cover is a baffle strike, whatever put it there. In the guarantee’s own words: “If a bullet hits the inside of the silencer, that’s an alignment or ammunition problem upstream of us. Call anyway — we will examine it and tell you what we find, and we’ll quote a repair rather than walk away.”
Alignment is exactly what a mount is for. Run someone else’s and that variable is yours — which is reason enough to look through the bore before you load, whatever you’ve threaded on.
Sight down it against a light background and confirm the path is clear and concentric. Ten seconds, every time, and it’s the difference between a silencer and a repair.
The short version
A mount is what holds the silencer on. HUB — Hybrid Universal Base — is the open 1.375×24 standard that lets any compatible mount fit any compatible silencer. Use ours or somebody else’s. Your silencer isn’t hostage to your mount, and your mounts aren’t hostage to your silencer.
Buy the mount you want. Buy it from whoever you like. The only reason we want you back is that this one worked.