Reaming a brass barrel?

[TNHillbilly]

I had a machine shop bore a brass rod out to make a pistol barrel. It's right at 5/16th's and apparently they bored from both ends, since it has some imperfections. I need to ream it to get a smooth bore. I know basically they use a square rod as a reamer. Can someone give a little more info as to how one goes about the process? I'm guessing, properly reamed out, it will be about .32cal

 

[streetsniper]

Try toad hall http://www.iowatelecom.net/~toadhall/index.htm They explain the process, you just have to build a reamer to suit you.

 

[Zonie]

I sure do hope you folks who are using brass to make barrels know exactly what kind of brass you are using.

Brass comes in dozens of different types and they are not all equal.
The way they are processed before you get them also has a great deal to do with their strengths.

Did you folks know that some types of brass have a yield strength of less than 10,000 PSI?
Other kinds of hardened brass has a yield strength of over 60,000 PSI.

Some brasses are very ductile with high percentages of elongation while some are quite brittle with very low percentages of elongation.

IMO, anyone considering using brass as a material for a barrel should do a lot of research and know exactly what they are using.

If one doesn't know what they are using they would be wise to classify it as the worst kind of brass and make sure the powder charges are very weak.

Just something to think about. :hmm:

 

[bingo1952]

A square reamer will and has worked for centuries but unless you want to do it PC/HC get yourself a spiral flute hand reamer. The final bore size will depend on the depth of the imperfections. Unless you have a method for starting the reamer straight you will very likely have some run out on the finished bore and you may have to have the OD turned between centers to get everything concentric. It sounds like they may have used a drill to put in the hole since they went from both ends. If they did this you may well have holes that do not share the same axis especially if a three-jaw chuck was used. They can be out as little as .001 thousandth to .010 for a worn one that is not being properly maintained. Most commercial reamers are capable of 8"-10" of depth and need a 1/64" to 1/32" smaller hole than the desired finished size. Make sure you do not let the chips build up in the flutes. This will mar your finished hole.