Quick way to trim and deburr

[Stats Shooter]

seems logical that uneven neck lengths would cause uneven neck pressure on the seated bullets if all bullets are seated to the same OAL or the same ogive to base length.

for a hypothetical situation lets take 2 bullets both seated to the cases with the same neck tension except case A has a bullet seated .3 into the case, case B was seated with the same settings so OAL would be the same but the bullet is .310 into the neck because of the difference in neck length. Bullet B will have appx 3% more force holding the bullet in the neck. How much would that affect the velocity I don't have a clue. I can attest that annealing after eah firing along with more attention to case neck prep and shooting techniques has dropped my SD's from the mid 20's down to low double digits and single digits along with fewer flyers and less vertical dispersion of my shots

The other reasons for consistent trim lengths would be the carbon ring that forms in front of the neck or in the instance of a case that exceeds SAAMI specs perhaps a pinching of the neck that extends past the throat and into the lands.

In my line of work, as an economist when we do empirical analysis, we have two different measures of significance. We have statistical significance, and economic significance. Statistical significance is a binary decision based off of a rigid criteria set. Even if it it only makes a 0.000001% difference, it can be statistically significant.
However, just because it is statistically significant, does not mean it is economically significant. If a certain action by a population results in a 0.00001% increase in "x", though it matters statistically, practically it is irrelevant. Medical research for example is fixated on statistical significance, and often ignores economic or "practical" significance.

My point is; I do not disagree that trim length uniformity makes a difference. it is just that, with any of these time consuming procedures, has anyone actually done any experimentation to see if "the juice is worth the squeeze" so to speak.

I absolutely anneal, not just for a more consistent bullet hold and resize, but because it adds longevity to the brass. I have seen this in practice first hand. I have tested just using a powder measure vs. weighing each charge, lubing bullets, mixing lots of primers, once fired case capacity, and more.

But I have not tested to see how much trimming matters in a practical sense, that is why I brought it up....and again, I am not talking about trimming when it gets too long for SAAMI standards, I am talking about uniforming and trimming each case, every time.

 

[hounddawg]

I have not been trimming each time but then I never annealed after every firing until I automated it. With the efficiency increase using the Lee unit I might start though. I think I will maintain a .003 delta max or X plus or minus .001 whereas when I was using my old method .005 in either direction was good as long as they were within SAAMI specs.

As far as any statistical difference I would be hard pressed to say. I have made so many changes to my reloading these past couple of months as well as as attempting to improve my range technique it is hard to say exactly how much of a effect any individual changes have made.

 

[Heavy Metal 1]

when you are cutting the ram is up and the case holder is directly below the die, chips only fall from a distance of 1/2 inch or so

I am sure some of the brass chips are ending up inside the case, probably not enough to matter but I will be tossing back into the tumbler anyway or hitting up with compressed air or both. Even when using the Wilson trimmer I would either tumble or blow out with air before priming

For 25 bucks for the main unit and another ten for each caliber die I can tolerate that. Compared to the price of the other units that do all three ops at once this thing is a bargain

Just tap the case upside down after trimming and any brass shavings will fall out. I do my trimming after it has been sized so I am confused as to why you would need to tumble them after trimming. That seems like extra work.

 

[hounddawg]

Unread #43
Heavy Metal 1 - I am confused as to why you would need to tumble them after trimming. That seems like extra work.

I am retired with more spare time than I deserve and any time spent in the man cave playing with my toys is time well spent.

Seriously, no real reason but sometimes I do. Most of the time I just fire up the air compressor and blow each one out from the primer end. Tapping would work just as well.

 

[disseminator]

Seriously, no real reason but sometimes I do. Most of the time I just fire up the air compressor and blow each one out from the primer end. Tapping would work just as well.

I would use caution doing that as most air compressors have a good deal of moisture in the air from the compression process and many applications require an air dryer for this reason.

 

[bigcountryeb]

I may have missed it but I didn't see anybody mention the RCBS x-dies. You do need one per caliber ($35-40) per die, but I believe they are supposed to completely eliminate trimming, chamfering and deburring after the first trim, champher and debur. I have one in.223 but haven't used it enough to report yet whether or not it works. If it does, I will be buying one in .308 as I absolutely hate brass prep while I enjoy the rest of reloading quite a lot.

 

[RC20]

I would use caution doing that as most air compressors have a good deal of moisture in the air from the compression process and many applications require an air dryer for this reason.

Usually not a problem. If you run it hard and hot for hours on end then it might.

Maybe not so good in the Middle or Harvey or Irma.