RA Tech CNC Machined Steel Outer Barrel for KSC MK23 Airsoft GBB Pistol

"I had to file down the blowback unit to fit it into the outer barrel. Its heavy and tight fitting and super nice.

"99.8% compatible with the KWA mk23 but you have to make sure it will cycle properly. The tab that sits in the recess of the slide sometimes is offset and if u don't feel like filing it down to make it fit (which won't be even close to perfect because of the offset) you'll have to come to the store or go through the return process.

Pros:
Threads are better than plastic
It's metal

Cons:
May have issues cycling
Barrel makes it heavier (possible pro)
Some barrels are defective
Gas consumption may increase

If you're looking to get a replacement barrel give this a shot.