I am about half way through building my polish underfolders in 7.62x39 and am now looking towards new projects.  I would like to build an AK-74 but I have a question on installing the barrel into the trunion.  I will use the 1/4 inch all thread method on my polish 7.62s.  What about the 5.45?  Big hammer or pressing seems to be the only way I can see installing the 5.45 barrel?  I do not like the idea of the big hammer and do not have a shop press.  Is there another method that I am missing (requiring few tools)?  Thanks.  

I used a smaller threaded stock on mine as well. I snapped two pieces but finally got it in.  I would tighten it down and tap on it with a hammer and tighten some more.