.308 round nose ream

[just bill]

Trying to make a round nose reamer for .308 for a couple different projectiles. Has anyone made one with a file? The reason I ask is the compound radii on the ojive seems a bit tedious for the use of a radius tool. I'm not a very patient wanna be machinist. This is for 100 yd accuracy in the 4" to 5" grouping, not sharpshooter accuracy.

Thanks,
Bill

[lead chucker]

I haven't made a round nose reamer but a few spire point and a couple flat nose for .40 and .44 all with a file. It takes time and a lot of polishing I'm sure they are not perfect but it works. I have been making three flute reamers. With my limited experience they are harder to make than a D-reamer but work a lot better. The bullets I have made the accuracy has been quite good. Lapping is harder because its not as repeatable for the laps.

[Kevin8888]

Buy a cutter with or grind a concave rad on a cutter (aka form cutter) then just cut it with that and polish after? As long as you don't go to hard or abuse it it could even be good for making matching laps.

[just bill]

Buy a cutter with or grind a concave rad on a cutter (aka form cutter) then just cut it with that and polish after? As long as you don't go to hard or abuse it it could even be good for making matching laps.

Thanks for waking me up. Been blind sided about radius cutters and over engineering, I forgot about a cutter. I've seen it done for aluminum duplicate parts.

Bill

[Kevin8888]

Thanks for waking me up. Been blind sided about radius cutters and over engineering, I forgot about a cutter. I've seen it done for aluminum duplicate parts.

Bill

No problem, I'm a machinist by trade so my life is all about making things faster/easier so I can make more money for my boss. Haha

[just bill]

No problem, I'm a machinist by trade so my life is all about making things faster/easier so I can make more money for my boss. Haha

I work part time in retail, it's all about the Benjamin.

[just bill]

I found this trolling the site. Wish I found it before I started to make my ojive cutter.
http://i913.photobucket.com/albums/a...ps21091163.jpg

Bill

[country gent]

I believe I would start with a round nosed 2 flute end mill ( 5/16" or 8MM) and indicate it in good then grind to form and sharpen this will save cutting flutes will be very close to start saving a lot of grind time. Once ground to form ink it up and back off the relief to a cutting edge. On the straight sides you may not remove enough to need to do much. We kept a lot of broken, dull, and worn out cutters at work for stock for this type of work. Saved a lot of time fluting hardening tempering, and such. A file may be to hard as is and may have surface imperfections that can cause cracking and breaking. The cutter is ready to form and finish. As to ogive a grinding wheel can be dressed to a cardboard form or gage and the ogive ground on. grind semi close redress wheel grind close redress and then finish. At work we had wheel of varying hardness and used a harder wheel for the forms but then they loaded bad also due to not breaking down fast enough. Its a trade off.

[just bill]

Country,
Thanks, however I am going to try the 2 flute and spoon. I have only one unused new ball end cutter and 3' drill rod and cold rolled to practice making reamers with.
Bill

[country gent]

Don't start in steel buy a length of hard wood dowel to practice on. Soak it over night in a good glue to fill grains and then let cure out, This will allow you to make the form and flutes easy with little wear to equipment and or cutters then see what it looks like. We save large pieces of card board for testing sheet metal lay outs for bending to make sure all the ears folds and lips matched and laid up together correctly before making the actual sheet metal parts. Was much easier to work the cardboard.

[just bill]

You are the first to point in that direction. Ill give it a try.
Bill