Shoei FG42 PFC/blowback conversion

Hi all
I hope this is ok to post here. I want to gather as much info as i can regarding the Shoei FG42 PFC/blowback rifle and conversion kit. End game for me would be to convert my type 1 or type 2, or both, into a half decent firing rifle, and hopefully the info will help others do the same.

I have owned the type 1 pfc FG42 before, many moons ago, and was not really impressed with how it performed. But did not really look into it too much, and just sold it on. So hopefully this time around we can delve into it a bit more, and get a better end result.

I will be uploading all the info i have found on the blowback conversion, please feel free to add what ever you can. I know there is limited info as the kit has not been made for over 20 years.

Thanks
Jay

Right.

How the Shoei FG42 blowback works:

Shoei's FG blowback works using an open bolt for both semi and full auto. The bolt itself is fixed in the 'unlocked' position by way of a spacer that is fitted behind the fake firing pin (circled in pic below), which stops the bolt running down the camming channel and rotating to lock.

The locked bolt system simply would not work for PFC firing, as the system relies on gases driving the gas piston back, which then rotates bolt to unlock it.



I got this info from Tomio, which shows some mods to the bolt and gas piston for PFC firing.
The first pic shows an extra cut out on the gas piston. i am presuming this is for open bolt semi auto firing, and to lock bolt back further than the original semi cut out, but not as far back as the auto cot out. On the pics I’ve seen of the conversion kit, the gas piston does not have this extra cut out on all of them, so maybe someone has added this to improve semi auto function.



The second pic is the info page, in Japanese. sadly i dont have a clue what it reads but the pics are quite helpful. it shows dimensions for the new cut out in the gas piston, and a pic of .  mod to the bolt lugs, which im thinking is to help the bolt from maybe snagging on the corners of the locking cut out in front of the chamber. this makes sense as the bolt could possibly have some slight rotational movement, and may snag at battery position.

Another modification is to the extractor on the bolt. A screw has been added to stop the extractor pinging off when under the stress of rapid fire, IF you ever got it to cycle numerous rounds lol.

Interesting. Please keep posting updates:)

Managed to get another bolt for the type 2 ( thanks Tomio ).
Will do the extractor screw mod on this.