Taper crimp

[Ian]

I recently bought a big chunk of 3/4" rubber horse stall mat from Tractor Supply to put atop a workbench in the garage. It needs cutting down on one side and I've been putting that off, so it's still on the floor in front of my tool box. After standing on it quite a bit doing powder-coating chores it might just stay where it is. Problem with the gun room is I needed something cheap at the time, and that carpet was something like three bucks a yard. All the nifty lock-together gym mats and rubber flooring was way out of my budget when all I had was 30 grand in savings and a year off work to build 3700 square feet of house for my bride.

Brass usually gets trimmed at work on my lunch breaks when I'm not fooling around here. Or in the garage where there's polished concrete. Don't remind me how much I need to break down and buy a powered trimmer, or at least a powered inside/outside deburring station. The last time I went through a bucket of .223 it about ruined my hands.

 

[fiver]

it still hurts the hands with the powered champhering type tools. [I hate champhering case mouths]
the size-trimming is super painless except for buying the dies, but it is also super fast.
I need about 3-4 more size dies to have a real good set.

 

[Ian]

You have the Dillon dohickies with the big electric motor and vac attachment that fit on top of the sizing die? Those are the berries. Some people make 300 Blackout brass from 5.56 in one step using those.

 

[smokeywolf]

Problem with hard flooring or a rubber mat for me is, any time I drop something small, like a taper or dowel pin, small screw, somehow it ends up in the next county; gone forever or at least until I don't need it anymore. Drop a spring?

Case trimmer, I motorized my Wilson trimmer decades ago. Keep forgetting, need to put a new power cord on it.

 

[Rick]

Had indoor/outdoor carpet in mine for a short while. Will never make that mistake again.

 

[RBHarter]

Kids kindergarten play mats are nice .

 

[KHornet]

Just concrete! Easy to sweep up and sort out the stuff in the dust pan.

Paul

 

[fiver]

I missed out on grabbing the 300 BO die a while back.
but you can trim some serious brass off a case with no issue.
I have made 7.65 argie brass from 0-6 in one pass and my biggest hurdle is in not just ramming the handle down but to use a smooth steady feed.

 

[KHornet]

I still have some 243's from formed 308 Mil brass that I did back in the early 60's.
Have probably 15 or 20 of them left from the 50 or so that I made back them. No
idea of how many times they have been loaded.

Paul

 

[Ian]

That's my favorite way to make .243 brass, the necks are thick enough and long enough when made from .308 and that tightents groups. Just make sure the loaded necks aren't TOO tight!

 

[KHornet]

Yep Ian you is correct!

Paul

 

[fiver]

the new SSA brass is like that.
it's stupid expensive though but at the time was the only 243 brass I could find.
I bought a bag and made the number one rookie mistake of just trimming and sizing and loading with the load I had been using in some other cases.

my groups blew up from about 3/4" to about 3"s instantly.

 

[Brad]

Ok Ian, take a look at this.


This is a 4° taper. Made a die tonight. It is currently on the Dillon and I will give it a go tonight. With a crimp at .469-470 it touches just the end of the case. You can see how much of the case is touched by the die.
I doubt the bullet is being altered in size in any meaningful manner outside the 1/32 of an inch or so that gets crimped.
Will be interesting to see how well it works over a 200 round run. More important will be seeing what the gun thinks. They do drop into the chamber just fine.

 

[Ian]

It think you got it licked. I'd adjust the die for another thousandth of squeeze and get solidly at or under .469" on every piece of brass in the collection if it were me, but ask your guns. The angle looks like it's doing exactly the same thing my Lee die does and that will give you the versatility to go all the way down to .465" without ruining the case tension, yet still turn in all of the bellmouth bulge when set to .470".

 

[Pistolero]

Brad. Again?

Save the hassle. This is well plowed ground. Buy a Lee TC only die - avoid the Factory Crimp Die with
the carbide ring - and be done with it.

Really, don't waste your time reinventing the wheel, unless you just like the excuse
to play on the lathe......ALWAYS a valid reason in it's own right..

And .465 with this kind of die hurts nothing, helps reliability of feeding and chambering.

Bill

 

[Ian]

I think it's neat that he made one just because he can, even if he could have bought one for less than $15...at the new Brownells store....which would have been a fine excuse to go to there too.

 

[Pistolero]

Yeah, and I can really understand getting into that whole thing. Having machine tools is just FUN, and I am
still learning with each project, so I know what he is doing - having a good time making stuff.

I am just getting started with indexable cutters, a whole new adventure for me. I have been grinding
my own tools and that works pretty well, but I bought a neat set of indexable cutters for the lathe and
it should make it faster and more consistent to cut, once I get all of them set up in their own
quick change holder. Then I'll be looking for new excuses to make stuff.

I haven't done this deep internal boring, and especially doing a particular angle like Brad did on this
one. Until you do something new, it seems a bit intimidating, then you learn a new skill.

Bill

 

[Brad]

This was more of a "I wonder if" kind of project. It made me really regret not paying more attention to trig. I wanted to calculate how large the opening would be if the .468 diameter ring was .5 into the die opening. When in doubt I make a quick drawing, photograph it, and send it to the daughter for verification. She eats this trig stuff up.
Bill, for the boring I used a small carbide insert boring bar. Bought a set off EBay for a couple hundred bucks. New it would have been over a grand, there was well over 200 in the inserts alone. Works like a charm for boring 1-2" deep holes under 1/2". Now I need to try one of the other 5 in the set!

 

[Pistolero]

Always interesting to learn new skills. A lathe has a nearly unlimited range of things to teach me.

Trig can be fun, if you need it as a tool.

I taught math for adults at work for a couple years. After we finished the basic curriculum,
through middling to upper level of algebra, I asked the 6 remaining students (many, at the
beginning just wanted to do something other than their jobs, most found that they didn't
really want to be there) who were really getting into mathematics whether they wanted
"more", and if so, what? They asked about trigonometry, which I agreed to, and management
approved of.

Two ways to teach trig - serious, understand the fundamentals of mathematics, and prep for going on
to more advanced math (boring), or just good old, practical trig for calculating triangles - which is really
pretty easy if you just learn it as a tool. We had fun with that and they were really
thrilled to "know trig". One guy was a woodworking hobbyist and had always wanted to
make a hexagonal table but couldn't figure out how to lay it out. After a bit of trig he
did it with no problems, and had a big grin. Teaching people who really want to learn
has been a real joy over the years.

Bill

 

[Ian]

Doesn't your tablet have an "iTrig" app? Just remember SOH CAH TOA for your angles. Trig tables should be available all over the internet, I'm a Luddite as you know so I still use a pocket reference.

I would imagine that all that trig goes wonky when you stick a boring bar in a hole and things start to deflect. One thing engine machining processes taught me is just how flexible even metals can be under even mild stress.