e-bay 312 reamer

[rolltide]

This one is not as cheap as the 223 reamer, but if you want to make a 312 bullet for your 303 or your 762x39, it is not a bad deal. I am going to make a 312 point form die and use my core swage and core seat from my 308 set.

http://www.ebay.com/itm/330875820588?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT


Rolltide

[customcutter]

Rolltide, I might be missing it but I don't see any cutting flutes on the tapered section of the reamer.

[rolltide]

I think I see cutting flutes on the front. It seems the leading edge of a reamer would have to be a cutting surface. How else could it work? Anyway, I ordered one, so I can tell you in a few days for sure one way or the other. I guess not many of us shoot .312 caliber. I shoot both British 303 and 7.62x39, so I am hoping to make this my first die project. $19 on the reamer and $17 for a die blank, and some time on the lathe will be a good deal if it works. If it doesn't work the first time, I guess it will become my .355 project. My main concern is going to be polishing the die after I use the reamer without increasing the die diameter over .313. With spring back, I am hoping if the die is no larger than.313, the finished bullet will be .312.

More to be revealed.

Roll Tide

[Prospector Howard]

The reamer will be too big for what you're shooting for, I'd think. The reamer should be 4 to 5 thousandths under what you shooting for to have enough room for lapping, depending on how smooth the reamer cuts.

[rolltide]

I was kind of afraid of that. I just got a lathe and I am very new to all this. I will put it to some use, maybe a good pilot hole reamer for 355 dies core swage or core seat dies.


Thanks,


Roll Tide

[rolltide]

I got the reamer today. It does have cutting surface down to the tip. Now I need to get some die blanks ordered an see if this is going to work.

[customcutter]

I got the reamer today. It does have cutting surface down to the tip. Now I need to get some die blanks ordered an see if this is going to work.

I started with 4140PH, learned to cut my own threads, etc. You can make a D-reamer from drill rod, either 0-1 or W-1. I had so much trouble making a D-reamer for .224 dies that I finally ground one out of HSS. I couldn't get the heat treat right and kept snapping the reamers.

[tiger762]

Check with Pacific Tool and Gauge for die blanks pre-drilled to various diameters. $20/each

http://shop.pacifictoolandgauge.com/index.php?main_page=index&cPath=310_67


I was kind of afraid of that. I just got a lathe and I am very new to all this. I will put it to some use, maybe a good pilot hole reamer for 355 dies core swage or core seat dies.


Thanks,


Roll Tide

[rolltide]

Thanks guys. I am planning to use die blanks from PTG. I believe they are annealed 4140, but I am not sure. Does anyone know if they are annealed. The web site gives temps for hardening, but suggests it is not needed. I think they assume these blanks will be used for reloading, not swaging.

Thanks again for your input. I can use all the help I can get.

Roll Tide

[customcutter]

Probably 4140 pre-hardened to 35-40 rc. Best bet would be to ask PTG. Shouldn't be a problem to cut, with properly hardened drills, reamers, etc.