useing a cnc to trim and champher brass

[black_ump]

iam a machinist as was thinking last night i could cut some jaws and write a program to trim my 308 brass that way every one is to length.

to set the machine up and to write a program would take an hr or less do you think this would be worth it or not ?

 

[Longshot38]

Re: useing a cnc to trim and champher brass

Why not. I've seen guys trimming on mini lathes before. Why not CNC.

 

[Victor N TN]

Re: useing a cnc to trim and champher brass

I am speaking to you as a tool & die maker with experience on NC as well as CNC machines.

Yes the machines can do it. But it's kind of like carrying around a sledge hammer to swat mosquitoes with. I use a custom made version of an accurate Wilson trimmer. But have used a Forster and Lee trimmers.

 

[black_ump]

Re: useing a cnc to trim and champher brass

hahahahaha

 

[memilanuk]

Re: useing a cnc to trim and champher brass

I'd be interested in how you plan on holding the case and dealing with any runout... not being a machinist I don't know if there is a quick/easy way to do that, but the examples I've seen pictures of where people are doing it on a manual lathe (mini or otherwise) looks like that'd be the big time sink. Probably slower than a Wilson trimmer, and way slower than a Giraud.

Now a case feeder for a Giraud trimmer... that'd be *hot*!!!

 

[DENAUS4]

Re: useing a cnc to trim and champher brass

Once you had your program and some jaws machined it would be quicker than doing it by hand. It would probably give you a more consistent length too. I say do it!
Cheers Lachlan

P.S Don't forget to turn ya Jaw pressure down

 

[black_ump]

Re: useing a cnc to trim and champher brass

ya i will have to turn my jaw pressure way down lol other wise crunch....

i think iam going to do just that, bore a set of small jaws and when a machine is down i can take the jaws out of my tool box and do my brass, id say in a half hr i could do 50+ caseings easy
would also like to drill some of the flash holes out to 9/64 so i can use a magnum primer in my subsonic loads

i would def hold a more constint length and my round out would be at most =/- .001 tops

 

[EddieNFL]

Re: useing a cnc to trim and champher brass

Don't know if it's CNC (probably not), but a friend trims and neck turns on his lathe.

 

[kombayotch]

Re: useing a cnc to trim and champher brass

It would be worth it if you were doing something like chopping down .223 to convert it to 300 Whisper, but not for general trimming. Why not just make your own 3-way trimmer?

 

[subgunr]

Re: useing a cnc to trim and champher brass

Well lets see...you could write a program to decap and ID neck size( dont spin the spindle,just use a mandrel in one of the tool positions and comand a -z axis feed)then trim and size neck OD. Now pick the part to the subspindle, and champer the primer pocket and make the flash hole consistant. drop it on the part conveyer have the next brass put in the spindle and go like hell again. $200,000 dollar CNC trimig brass or making parts. Ill use the old manual trimer. just saying. I needed the post count also.

 

[black_ump]

Re: useing a cnc to trim and champher brass

ya on my lunch time its cool..... why should i do the work when i can have the machine do it for me !!!!