How important is deburring and chamfering?

[Al Lu]

Bart, any chance you can post a picture of "Trim, de-burr, and chamfer with a Girard case trimmer in one step."? I want to get a good idea of what a trim job looks like? The one that I had looks kind of sharp.

 

[BartsBullets]

Bart, any chance you can post a picture of "Trim, de-burr, and chamfer with a Girard case trimmer in one step."? I want to get a good idea of what a trim job looks like? The one that I had looks kind of sharp.

They can be sharp but the cutting tool is adjustable so you can take that out.

Bart

 

[chop house]

Even after you chamfer in and out look at the mouth with a 12x Loupe. Rough as heck

i was struggling with some 22-250 loads smoking the necks even at midrange pressures. also had way too much vertical showing. measured case necks using tubing mic and seeing over 0.002 non-uniformity.

so, a while back i thought i was 'over' chamfering/deburring thus turning the mouth into a sharp knife edge, and i started going easy with the debur tool. too easy it turns out. had a neck fail so inspected under microscope:



non-uniform swaged lip on case od:



luckily i had a few prepped yet unloaded cases from the same batch:




so, yeah.... inspect with a magnifier to check your procedures. and keep your cutters sharp and your brass not too soft

 

[JMayo]

Benchrest, 6mmbra
I Deburr New brass. From then on I watch for ding spots. Other than that I do not add wear.
Never have shaved copper. BT Bullet fits right in mouth. Seats with 25-35 lbs of force.

If I drop them I use hand held expander to re round then resize neck in the press.