Deburring And Chamfering

[Gun Geek]

An article in this month's Blue Press, and a couple of references to it here have made me start thinking about an old question I have.

Do we really need to deburr the outside and chamfer the inside of the case mouth on rifle rounds?

In the reloading references I have, and lots of other sources, this operation seems to be absolutely required. However, the article in the Blue Press about the Arizona Youth team, they specifically say that deburring and chamfering is not required (since the Dillon trimmer makes such a clean cut).

I have been loading blasting 223 ammo (100yds and less) this way for a long time. I've pushed this ammo to 400yds with good results, the Arizona kids are pushing it to 1000yds, so I'm not sure I understand why it is necessary to do the deburr and chamfer step.

What do you think?

[EricW]

On some factory new brass, it is absolutely necessary if you don't want to shave jackets. However, if you're not shaving jackets on whatever brass you're running, why bother?

[sargenv]

I'd always chamfered and deburred mostly since the bullets I seat are flat based bullets. I might try not chamferring and deburring if I had a boat tailed bullet, but currently I do not. If I don't chamfer the case, I will probably wind up crushing cases since they will tend to not want to go in. I'm reluctant to try it on my Sierra 69 gr HPBT's, but maybe I'll try it just for grins and see if they seat ok and then shoot ok.

Vince

[TBF]

IMHO if you have a sharp edge after trimming you should remove it before you seat a bullet. Pull a couple of bullets sometime and look at them. Does it matter ? Dunno.

The outside of the case should not have a ridge around it either or chambering might not be so swift, not to mention the whole concept of crimping a case neck with a burr around it's edge.

I avoid the whole problem by using a Gracey trimmer and not crimping.

Take my advice with a grain or three of salt though, I never shoot past 300 YDS.

Travis F.

[John Dunn]

Giraud case trimmer saves me from worrying about this, when I was using a Wilson it would shave bullets all the time, so I would always chamfer and debur. Maybe a Redding Competition seating die combined with a boattail bullet would let you skip a step. I'm sticking with the Giraud (awesome gizmo!).

[Gun Geek]

So the only issue to worry about is shaving jackets? If I pull bullets and the jackets aren't shaved, were good to go?

Anything else?

[George]

Yeah, that's basically it. If the case mouths are clean enough to seat the round without shaving, then let er' ride. If there is a noticeable lip on the outside and you crimp, it is not a bad idea to remove that from the crimp equation too.

If you are looking for the most precise ammo possible, case prep is a lot of it and clean case mouths do mean a little bit downrange. Not worried about rat's ass accuracy, then you are probably good to go even if they are a little ragged.

Example: a few years ago when I first started using Scharch 100% processed 1x .223, the case mouths were pretty much ready to go. In the last three batches of 2000 I have been through in the last 12-16 months the case mouth prep level has gone downhill. The inside was shaving my SMK's and the outside had enough of a rim to screw up my polite crimping routine. Now I debur and chamfer for my match grade 1/2 moa stuff with SMK's in it. I let my 55gr short range blasting ammo go through the press just like it is and even though the Scharch brass shaves the bulk Hornady 55's I use, they still hold around an MOA so who cares for this stuff.

BTW, I do not under any circumstances consider the Dillon case trimmer a match grade trim and load device. Only the Giraud and the Gracey can live up to that claim. The Dillon end result is OK, but not at all what the other trimmers I mentioned turn out.

--

Regards,

[Tom Freeman]

Cant hurt, might help.