Home Forums Hunting & Shooting Custom Rifles & Wildcats 257 cz brno 21

Recently purchased a cz brno model 21 in "257 roberts" gun arrives and the barrel is clearly marked "257 ack imp" guess someone couldnt read!!! Now im also questioning it being a model 21 , receiver is clearly marked "Ceska Zbrojovka brno" i dont see a model number, from my research i see 21s had butterknife handles and dual triggers but i see also it looks like it was popular to single trigger it and change bolt to round knob since the safety is better and the throw is less so you can use shorter rings .... I see other topics about these guns and looks as if there are some guys who know these guns well , hoping someone can give me some insight on this rifle

Post some pics and you will have lots of guys helping you out.

Do a search, A lot of info is out there.

One of you more experienced guys help me out here,but can't you shoot the parent cartridge just fine out of any "ack imp" caliber? I always thought the "ai" just helped with case capacity and neck stretch after the initial firing. If that's the case,then the caliber mistake is no issue.

You can indeed fire a standard factory .257 Roberts in an improved chamber - that is how brass is formed. The barrel has almost certainly been replaced as no Model 21/22 rifles were produced in a .25 caliber. The bolt knob is likely a replacement; however near the end of production there were some round knob guns produced. The bolt knobs have a distinct dimple in the center - same knobs as used on the zg47. Pictures would be useful.

John