Why Your SIG P322 Rear Sight Won't Hold Zero (And How to Fix It)
You sighted in your SIG P322, put a few groups right where you wanted them, and felt good about it. Then a couple of magazines later, your shots started creeping — high, low, never quite where the sight says they should be. You re-zero, and it happens again next range trip.
You're not losing your touch. It's the sight.
The P322 rear sight has a known elevation problem
The P322 is a genuinely fun .22LR — light, accurate, and a blast to shoot. But a lot of owners run into the same frustration: the rear sight won't stay put. Specifically, the elevation adjustment drifts under recoil. Even the modest recoil of a .22 is enough, over dozens or hundreds of rounds, to let the adjustment creep out of position.
The result is a point of impact that slowly walks away from your point of aim. It feels random, but it's mechanical — and it's repeatable enough that once you know what's happening, you'll recognize it immediately.
Why the factory design drifts
The factory rear sight uses a cam-lock style elevation adjustment. In theory it holds your setting through friction and tension. In practice, that kind of lock is exactly the type of mechanism that vibration works loose over time. Every shot is a tiny impulse, and those impulses add up. There's nothing positively locking the elevation in place — so it slowly gives.
This isn't a defect you caused, and it usually isn't something a good cleaning or a careful re-torque fixes for long. The design itself is the limiting factor.
How to confirm it's the sight (and not you)
Before you change anything, rule out the usual suspects:
- Shoot off a rest or bag. Take your hold out of the equation and fire a group. If the group is tight but centered in the wrong place, your fundamentals are fine.
- Mark your elevation setting. Note where the adjustment sits, shoot a few magazines, and check it again. If it moved, there's your answer.
- Check consistency across sessions. A sight that needs re-zeroing every single range trip is drifting, not a fluke.
If your groups are consistent but your zero won't stay, the sight is the culprit.
The fixes, from band-aid to permanent
Re-tightening and thread locker. Some shooters try to snug things up or add a thread locker. It can buy you a little time, but you're still fighting the same cam-lock design — and thread locker on the wrong material can create new problems. This is a temporary patch at best.
Staking or DIY modification. Handy owners sometimes try to mechanically pin the adjustment. It can work, but it's fiddly, it's permanent, and if you get it wrong you've damaged a factory part with no easy path back.
A drop-in replacement that locks elevation. The cleanest fix is to replace the cam-lock mechanism with one that positively holds your setting. That's exactly the problem our SIG P322 Rear Sight Replacement was built to solve.
How the set-screw design solves it
Instead of relying on friction, our replacement swaps the factory cam-lock for a locking set screw. Once you set your elevation, the set screw holds it there — round after round, range trip after range trip. No slow creep, no re-zeroing every time you shoot.
A few things worth knowing:
- It's a true drop-in. It reuses your factory sight blade and parts and installs in minutes with basic tools. No gunsmithing.
- It keeps your sight picture. You're replacing the mount, not learning a whole new sight.
- One install note: don't use thread locker on it — the set screws hold securely without it, and thread locker can react with the material. (Details are on the product page.)
Stop re-zeroing every trip
The P322 is too good a pistol to fight with a wandering zero. If your rear sight won't hold, the problem is the factory design — and it's a fixable one. Lock your elevation down once and get back to actually enjoying your range time.