Took the P64 and my other Maks to the range for some testing. Could only do 25 rounds each because I took the Wolf steel case with me and the range doesn't allow steel case. Had to buy 100 rounds of S&B from them.
Test distance: 7 yds
Method: Lined all 4 with the mags loaded but not inserted. Snapped the mag in on the 1st one, racked it, decocked it, 1st round was DA then SA for the next 4 rounds.
The best results were from the Bulgarian Makarov, the P83, and remarkably the PA-63. They were very smooth in both DA/SA, the SA had a slight wall before the break, recoil was excellent, and my shot placement was also very good. The PA-63 failed to lock on the last round, but that may be due to an aftermarket magazine. All the others worked flawlessly.
The P64 gets mixed results but it may be attributed to the 18# Wolff hammer spring. In DA I could put my shot pretty much on target but all hell broke loose on SA mode. It was a hair trigger and I would calculate it being no more than 2#s.

My shot placement was all over the place since the SA trigger was way too light. Have to try it with the stock hammer spring and see what happens. I also have the 22# recoil spring installed and it seemed to work well, along with the Poilishiron grips, to tame the recoil. Didn't have the time, or ammo, to try it with the stock grips plus,the range was full and I was short on ammo and time.
As I'm cleaning it now, I dry fired the gun on SA and I don't feel any resistance/wall before the break. Two things come to mind. 1) The 18# hammer spring is not the right thing to do or, 2) there's something internally wrong with the SA part of the hammer, sear, trigger bar interface.
Any comments are appreciated.