Since oppressive regulations made silencers into durable goods (as opposed to disposables as in New Zealand), periodic maintenance is required to retain performance. Rimfire silencers are especially susceptible to fouling over time, filling up with carbon and lead. Since they are usually made out of aluminum for light weight, cleaning becomes a careful balance between dissolving the residues and protecting the anodized finish. It’s a lot easier to work on take-apart designs than on sealed models.
The single piece is more robust than individual baffles and harder to lose. The core and the tube are aluminum, but the threads for attaching to the muzzle are steel, both for durability and to avoid galvanic corrosion between dissimilar metals at the threads. The square form on the front is to aid disassembly in case the threads become fouled up too much for unscrewing them by hand.
Read the full review here.