Way to go,,,,great fun project. I bought [another] CZ 527 in 7.62 x 39 a few months ago. I've shot several of the 7.62 x 39s as a friend owns a custom gun company and buys a lot of CZs for custom rifles. Anyway I bought one because, well, as you say, I WANTED one. I"ve had dozens of rifles and own 2 12x36" metal lathes just for rebarreling whatever I want to. I was actually going to rebarrel this rifle to a 30 [308"] PPC just for the heck of it. Well, as some of us do,,I shot the carbine 'as is' and now want to keep it in the origional chambering and tinker with it some more. One thing I DID do was to take the barrelled action out of the walnut CARBINE stock since it has MORE DROP to the comb for use of the carbine's open sights. I have an extra CZ 527 walnut stock from a 22 Hornet American that was rebarreled to a 17 Ackley Hornet and put into one of the Kevlar CZ stocks. Now the 7.62 x 39 carbine is perfectly aligned for scope use. I removed the barrel and open sights, turned it in the lathe to remove the rear sight dovetail 'dog knot' so it was a perfect fit into the CZ American stock without having to inlet the slim forearm for the barrel knot. While off the action [boy are they on TIGHT!] I dialed in the muzzle to under 0.001" runout and cut a new angled crown. As good as the barrel shot before, it did have some burrs visible only under magnification. Have Lathe, Will Crown~!
A friend has a box of Hornady Vmax bullets made in .310" caliber just for this round. I have been promised a box of them for testing. Hornady made a limited run of them if I understand right.
Anyway,,,GREAT fun to read about your experiment. Here a 30PPC reamer has been made, but I am having too much fun with this factory barrel to pull it and replace it. Isn't it amazing how such a NON MAGNUM round can be so much fun. I've made mention before but will repeat here: My longest standing position kill shot at deer was made with a 4X scoped SKS at 125 yards. High straw grass made kneeling impossible. One shot, one nice venison doe. The 7.62 x 39 is very capable for deer in my opinion and experience.
Will watch your posts.
Projects in mind for consideration:
.308 PPC [reamer now purchased, used by others and VERY ACCURATE~!]
7.62 x 39 Improved [still .310 factory bore]. One question is: what would steel cased ammo do if fired in an improved chamber?
Longer barrel in same [you've done just that].