9mm ak from scratch
i have been pondering this for sometime. i wanted to see if i can come up with an alternative to the typical bolt modifications. given i really handy with CAD, i have cycled thru a few iterations for a "turn key" solution.
my objective was to get the bolt and trunnion as simple of design as possible so it can be milled easily. i am trying to get some time on a friends 3d plotter for some working models and then to a cnc.
nice. I propsed a scrath build a few years back ( likely for the x25 ) i went so far as to buy a end mill to do the bolt face and a few other bits of tooling. ther eis now reason a blow back could not be done with out a kit with a few original pieces like the dust cover, and other cheap essy to get original parts. t the whole build if you have a mill could be done for like $100 with no kit less if you are really reasorceful' I have always felt a blow back bolt/carrer assembly would sell if it was under $75. it could be one piece with a screw in guide rod/piston. the reciver could be a standard AK or a roll your own. when you make that trunion make a good place with some ,meat to screw a optics rail in place.
Your set up could be used for every thing from a 17 hmr on up to most any pistol calibur with just a few easy to obtain pieces. make the carrer so weight can be added or adjusted for various caliburs.
I always thought about this idea too because after seeing numerous threads on blowback conversions it just seemed ghetto to weld the bolt and carrier together and seemed like a waste of a perfectly good bolt, bolt carrier and trunnion that could be used on a rifle caliber project. the simplest way to do the extractor would probably be to drill a hole and use an uzi extractor. If you make a few sets of bolt and trunnion I might be interested in a set.
1bg thats the whole idea. the front rod is mainly to add mass for whatever caliber you choose. i still havent figured out the extractor yet. i am leaning toward something similar to whats on ar. i tried to keep the bolt and the trunnion very simple with everything being easy to cut on a basic mill.
seems like a extractor for common pistol was easy. ill find my old thread and link to it. i bought a extractor to use but never got the build off the ground. i bought the x25 reamer and every one wanted a barrel so i did barrels and never got my gun built then the ammo went away so i just never got to it.
I bumped up my old thread. it was a VZ ejector tht i had planed to use. i have it some were still.
hope the old thread will give you some ideas. Id lke to still do a few blow backs
if some one could CNC some bolt/carriers cheap they would sell.
cool thanks. i want to run a set on the 3d plotter. it will give plastic parts but its a good first run to see if there are any hidden snags. our structures lab just got a haas cnc. i am good friends with the lead tech and he says they can run a few "test" projects as a training exercise. they will not have it completely installed until mid january. this sort of pushed to finish these drawings. i have been playing around on diferennt models for over a year.
Originally Posted by 1biggun
is this guide rod operated?
no when i was saving the cad models to jpegs i brain farted and deleted the rod. it looks just like the front section of a typical ak carrier minus the gas piston. i drew this as separate piece as a means of easing the build process. it is basically a cylinder that pins into the bolt.
Originally Posted by BlackFetus
although, a guide rod wouldnt be a bad route to take as long as i can maintain the bolt weight.
did some rough math. will calc actual when i get back to the office.
from the Sub Machine Gun Designers Handbook
9mm bolt = 1.1-1.5lb
4130 steel weighs 0.283 lb./in³
required volume= 3.88-5in³
blowback ak bolt(approx)
l=3.55 w=1.25 h=1.25/2
aas the model sits now, it may have the weight to survive as a blowback guide rod build.