making a 7.62x39 bullet reamer.

https://www.youtube.com/watch?v=M8O4FiOfo78 this is how im making my reamers on my mill.

i decided to go ahead and make a 7.62x39 reamer to make swage dies for bullets for my sks.. this is a piece of 3/8in drill rod that is annealed and im using a small 1/4in carbide mill to cut the flutes. every flute is cut this way using a spin indexer to a depth of 0.095in and there are 4 flutes in all.

i cut the flutes, heat treated it, cut the reliefs on the back of the flutes and then sharpened it.. i already done a die with it and the bullets come out at exactly .311 full length of the bullet, which is a lot better than the last die i made that had a bad taper. i will not be using 1045 for dies again. i went back to the grade 8 bolt material as it seem to do well at lower temperatures and hardens up a lot more predictable..

i did figure out why the dies had a taper in them... being i was manually putting on the ogive portion of the reamer with a file i guess i was getting into it a little with the file when trying to blend it in with the shank. to get around this i left about 0.004in more on the shank than i needed and put the ogive portion on the reamer and then come back and skinned it to size and blended the little step.. it worked very well as the bullet is the same size all the way from the ogive to the base now. i also reamed the die b4 and after i heat treated it. i first reamed it with the .308 reamer b4 heat treating it and then after heat treating i come back and cleaned it up with the .311 reamer. the .311 reamer was not happy but it did cut. all i was taking out was 0.003in so it was no big deal.

Attachment 207156

the picture is of the reamer, the die i made with it, the swage punch and the ejector pin. there is also a pretty much perfect finished .311 bullet.

Attachment 207157

Neat! What weight bullet are you making? Sounds like a great setup for those of us who load this cartridge.

That is neat!! I wish I had the training in metal work but I enjoy following you fellas as you share your projects.

Good Job! That is basically how I've done chamber reamers only using 6 flutes and with a tailstock to support the non indexer/dividing head end since they're longer and already have a 60 degree center hole from being turned on centers.

i will be doing 125gr .311 bullets and be capable of 130gr .311..

but here is a few of the steps i use to make my reamers..

step one.... https://www.youtube.com/watch?v=I43JnePawZg

step two....https://www.youtube.com/watch?v=6gZFnH1Y0v4

step three....https://www.youtube.com/watch?v=gwxRY0IHHSU

the video posted above of the cutting the flutes is the fourth step. the fourth step is followed by hardening in my oven at 1,450*F for 5-8 minutes and quenching in water. then comes the cutting reliefs on the back side of the flutes for clearance.

https://www.youtube.com/watch?v=B6zxfPdXf1c

this is for those asking about exactly how im cutting the flutes and the reliefs on the back side. hope this helps.. while it is possible to use a small grinder to put the reliefs on the flutes it is also possible to go to far to fast or to burn the flutes if you get them too hot.. i use a small diamond file for control and because it does not put any heat into the reamer messing up the heat treating.. with a new diamond file you will be surprised at how fast it does go.. took less than 10 minutes to do 4 flutes..

and for the darn Yankees, no laughing at the accent... :p