Chamfer and De-burr.

[supercorndogs]

Are there problems associated with chamfering too deep, or is this just a personal preference? The only thing I have ever been told on the subject was that, "you don't want a knife edge on the top. I try to chamfer pretty conservatively with a VLD tool. I see pictures of brass on the sight that I think is chamfered way too deep, but then I think what possible problem could it cause.

The only thing I can think of is needing to trim more often. And that is a wild ass guess if that even happens.

 

[Supersubes]

I don’t think there are problems really. I do the same as you essentially.

 

[pmclaine]

I use Hornady 3-1 to perform this most onerous task.

I count to 3/one thousand on each task and call it good. Primer pockets may get a little extra time.

 

[straightshooter1]

Are there problems associated with chamfering too deep, or is this just a personal preference? The only thing I have ever been told on the subject was that, "you don't want a knife edge on the top. I try to chamfer pretty conservatively with a VLD tool. I see pictures of brass on the sight that I think is chamfered way too deep, but then I think what possible problem could it cause.

The only thing I can think of is needing to trim more often. And that is a wild ass guess if that even happens.

Not being much of "problem" but it does reduce the neck tension/friction holding the bullet a little (very little).

As you allude to, one may need to be sure to trim the case after cleaning as a thin/sharp edge will peen and roll over where that can make for rough seating of the bullet. If one trims after every firing, as I do, then it's not an issue. But if a case doesn't lengthen enough after sizing to necessitate trimming, then that peened interference with seating just might be a big issue.

 

[Steel head]

Just enough to break the edges.

 

[spife7980]

I like my deep chamfer knife edge result from the giraud.

 

[308pirate]

The whole point of chamfering the inside and outside edges of the case mouth is to knock off any burrs that will interfere with bullet entry (the burr on the ID) or with the seating die and/or rifle chamber (the burr on the OD).

So long as you get rid of the burr, the length and angle of the chamfer is irrelevant. Any arguments or thumbrules about how much is too much are complete bullshit and have zero basis in any fact.

Change my mind.

 

[Rocketmandb]

The whole point of chamfering the inside and outside edges of the case mouth is to knock off any burrs that will interfere with bullet entry (the burr on the ID) or with the seating die and/or rifle chamber (the burr on the OD).

So long as you get rid of the burr, the length and angle of the chamfer is irrelevant. Any arguments or thumbrules about how much is too much are complete bullshit and have zero basis in any fact.

Change my mind.

Exactly this. I chamfer/deburr the minimum necessary to get rid of any brass that sits beyond the nominal case mouth. Going beyond that just costs you time and a teeny bit of brass.

 

[Milo 2.5]

I never deburr a case unless with a 3 way cutter. I used to really put a hard vld chamfer on my cases, partly because I hate to trim and if by chance a case was too long, it may be more forgiving<my thought, no one elses.
But I have read, really no gain to a long chamfer, and more to lose, so I just kiss the mouths today if I chamfer. But i'm with spife, let the Giraud do it's job if I trim. Now that I think about it, I have been going 3-4 firings between trimmings w/o re-chamfer, new to me, used to do it every firing, No noticeable differences down range.

 

[Rocketmandb]

Now that I think about it, I have been going 3-4 firings between trimmings w/o re-chamfer, new to me, used to do it every firing, No noticeable differences down range.

I only chamfer/deburr the case mouth if I trim. Like you, I don't trim even close to every firing.

 

[Milo 2.5]

So long as you get rid of the burr, the length and angle of the chamfer is irrelevant. Any arguments or thumbrules about how much is too much are complete bullshit and have zero basis in any fact.

Change my mind.

Lol, I don't absorb much when it comes to the internet and load dev, but there are some whom I read and pay attention to. This very discussion came up on accurate shooter, they were some pretty big names and guys I trusted who were adamant about too much being detrimental. Truthfully, I bought into it.
But, big but, lot of the guys talking shoot dashers with short neck lengths, was this a factor, I do not know.

 

[Mechdesigner]

I try to chamfer/deburr only enough to break the edges, depth does not matter as much as consistency. My least favourite part of brass prep...i need a giraud!!!

 

[Precision Underground]

All that’s needed is to knock the corners off. You only have corners when new or after trimming.

 

[lash]

In the interest of consistency I lightly hand chamfer/deburr ID and OD every time after tumbling. I happen to believe it takes out any dings or nicks from the case mouths and eases bullet seating. I use a simple Wilson hand tool, a single twist inside and out each time seems to work.

In addition, I’d like to believe that it contributes to the fact that I rarely have to trim my .260 brass. And that’s over more than ten firings minimum. Current set has over 15 firings and only lightly trimmed once at nominal spec. length.

Whether or not it contributes to the good results I get, I’m sure that it doesn’t detract.

 

[Codiekfx400]

The whole point of chamfering the inside and outside edges of the case mouth is to knock off any burrs that will interfere with bullet entry (the burr on the ID) or with the seating die and/or rifle chamber (the burr on the OD).

So long as you get rid of the burr, the length and angle of the chamfer is irrelevant. Any arguments or thumbrules about how much is too much are complete bullshit and have zero basis in any fact.

Change my mind.

I know from experience I won’t change YOUR mind but if seating a flat base bullet a decent chamfer makes the seating process slightly easier.

 

[Rocketmandb]

In the interest of consistency I lightly hand chamfer/deburr ID and OD every time after tumbling.

Actually, you brought up a good point and something I should add to my post about not chamfering, etc. unless I resize trim:

I don't tumble, so I don't have issues with case mouths getting peened.

 

[2aBaC̶a̶]

Forster 3in1. trim/debur/chamfer as needed. About as uniform as it gets.

 

[shoot 51]

Actually, you brought up a good point and something I should add to my post about not chamfering, etc. unless I resize:

I don't tumble, so I don't have issues with case mouths getting peened.

If you don’t tumble, what media do you use

 

[308pirate]

Lol, I don't absorb much when it comes to the internet and load dev, but there are some whom I read and pay attention to. This very discussion came up on accurate shooter, they were some pretty big names and guys I trusted who were adamant about too much being detrimental. Truthfully, I bought into it.
But, big but, lot of the guys talking shoot dashers with short neck lengths, was this a factor, I do not know.

If they're so fucking sure, they should be able to offer irrefutable evidence. But I bet all they have is excuses when asked for hard data and facts.

The shooting world, including the competitive shooting world, is full of bullshit artists who use their expertise in one area to fool the simpletons about their expertise in other areas. It's a logical fallacy, among the many so prevalent in the shooting world. About the only part of the shooting sports exempt from the sea of bullshit is the elite World Cup level, where the money is there (in Europe anyway) to put sports science into shooting.

 

[308pirate]

I know from experience I won’t change YOUR mind but if seating a flat base bullet a decent chamfer makes the seating process slightly easier.

You're just agreeing with me in different words.

 

[Milo 2.5]

If they're so fucking sure, they should be able to offer irrefutable evidence. But I bet all they have is excuses when asked for hard data and facts.

The shooting world, including the competitive shooting world, is full of bullshit artists who use their expertise in one area to fool the simpletons about their expertise in other areas. It's a logical fallacy, among the many so prevalent in the shooting world. About the only part of the shooting sports exempt from the sea of bullshit is the elite World Cup level, where the money is there (in Europe anyway) to put sports science into shooting.

No doubt there is no control on what is published, it has always been an individuals job to sort through what he reads, or hears. On the other side of that most of us have sources that we trust, for no reason has surfaced not to.
I monitor my process each time I prep brass, and most likely will never size and prep more than 10 cases initially to shoot and make decisions if changes are needed. Like I said in my first post, it is rare I care about who is doing what, I have a routine and I follow it, if it is not satisfactory, I alter it.

 

[Rocketmandb]

If you don’t tumble, what media do you use

None - I use an ultrasonic cleaner with Bore Tech's Case Clean. It doesn't come out the shiniest, but it's clean - primer pockets and all. If there is a particularly egregious area on a case, I'll do a quick pass with a polishing cloth. If I want it really shiny, after the ultrasonic, I'll dry tumble for an hour or two. But then, I'm finding I care less and less about how things look, and more about how long it takes - and how it shoots, of course.