Is a Bulgarian pin diameter 4.5 or 5.5???

Quoted: Is a Bulgarian pin diameter 4.5 or 5.5???

4.5mm,....

the russian AK-100 series plastic stock is a 5.5

you should be able to put a AKS-74 stock on a AKS-74U with no problems,...but if you want to make a AKS-74M or AK-105 you need the plastic stock with the bigger pin.

Yep.

Can't drill out/ream the hole to the larger size?

Quoted: Can't drill out/ream the hole to the larger size?

you could,...but there is alot of stress on this part the hinge pin and hook are whats keeping the stock on durring firing,..it is bet to just use the 4.5mm trunnion with 4.5mm pin and 5.5mm trunnion with the 5.5mm pin

the angle of the stocks is diffrent,.. so if you have a AKS-74 and wan to turn it into a AKS-74M,..and actually managed to modify the stock / hinge,...it may or may not hook / latch in place when folded

OK, the trunnions are different too then.  I am working on a 5.56 Krinkov to be a post-sample one day.  I got the Bulgarian side-folder, ASS-U-MEd it was a direct copy of the rolled strut Soviet stock.

just because it is Soviet does not mean it is the same size. and you are exactly right,.. the trunnions are diffrent.

now when everyone was in the USSR a Russian stock would fit a Bulgarian rifle and vice versa,..these where all the 4.5mm type,...now the AK-100 series rifles,.. no one else has those except the Russians and are the 5.5mm type


yeah i would love a 5.56 Krink,.. i want to build one on a milled reciver with the AK-100 series butt stock.,..but i can not afford a post sample,.. but man that would be fun.

From the AKForum.com

"The Russian Polymer stock will fit on a Bulgi rear trunnion but you have to make a new henge pin and drill out the top loop of the henge on the rear trunnion. Just make sure you drill ONLY the top loop of the henge. It's not a very hard mod. to do. I used a small grade 8 bolt. I cut the head and threads off then put in my drill press and held a file on each side until I got the larger part of the henge pin to 5.5 mm the smaller or bottom end (stepped down part) of the pin I made the same size as the Bulgi. pin. It only took about 1/2 an hour to make. Then I put several heavy coats of Navel Jelly on the raw metal of the new pin and inside of the upper henge loop to give them a nice phosphate coating and prevent rust and it gives it a correct look. The Russian pin is 5.5mm and the Bulgi is 4.5mm. I hope this helps."--Steelcore1964