There are a number of reasons for a revolver spitting or seeming to spit.
I've had several cases where a "spitting" revolver was being shot in an indoors range and the between-line baffles were deflecting burned powder particles back onto the shooter.
As for the reasons a revolver will really spit:
The forcing cone and/or the front face of the cylinder have fouling build up. Clean the cylinder face, and use a Lewis Lead Remover to clean the forcing cone. The Lewis kit is the only effective and practical way to really clean the forcing cone, and all the older revolver shooters have one.
A revolver that's out of time. This means the action is worn or defective, and the revolver is failing to lock the cylinder up before it fires. This means the chamber isn't aligned and locked, and the bullet is actually not entering the bore cleanly. As it enters off center, part of the bullet is being "shaved" and is ejected from between the barrel/cylinder gap.
A revolver who's alignment is off. In this condition, the revolver may be perfectly in time, but for various reasons, the alignment of the chamber is off, and the chamber isn't aligned with the bore when it fires.
Again, the bullet is being shaved, and metal is being ejected.
A revolver with too much barrel/cylinder gap. In this condition, due to a factory defect, or wear or abuse causing cylinder end shake, there may be too large a gap between the barrel and the cylinder. This large gap allows material to be ejected.
Sprung yoke. A bent, "tweaked", or sprung cylinder yoke can cause the cylinder to not align properly. This is usually a symptom of abuse, often caused by "Bogarting" the gun. This is caused by slamming the cylinder open and shut with a flick of the wrist.
Worn lock-up. A revolver that has a worn or abused lock-up can allow the cylinder move in and out of the frame, again causing alignment problems.
A cracked or eroded forcing cone. Shooting light, hot Magnum ammo like the 110 and 125 grain bullets can cause cracks in the forcing cone, or the hot gasses can erode the cone to the point that material can be ejected.
My first move would be to give your revolver a GOOD cleaning, especially in the forcing cone, and the front face of the cylinder.
Inspect the forcing cone closely, looking for damage.
Check the cylinder for end shake, (The cylinder can be moved back and forth in the frame is end shake).
Check the barrel/cylinder gap with a feeler gauge. It should be somewhere between a minimum of about .004" to a max of .010".
Try another brand/type of ammo.