.22 LR Semi Auto AR Style

[Mattnall]

Do they have a proprietary magazine though or can they take Black Dog etc?

They do use the Military mag insert (10rnd) as the bolt is the military M261 insert without the chamber.
Blackdog make a M261 compatible magazine.

They will not work with the Ciener based compatible mags.

[nfarmer]

now sorted Sig Sauer 522 SWAT

[BamBam]

now sorted Sig Sauer 522 SWAT

Good choice

[safetyfirst]

Good bit of kit!

[saddler]

now sorted Sig Sauer 522 SWAT

Nice rifles, but about as AR style as a housebrick.
The folding stock is a good feature. Always lked the original Stg.90