Case prep centers

K

kilotanker22

New member
I am shooting so much and stock piling ammunition lately that Brass prep is taking me way too much time. I would like to hear recommendations on case prep centers. Something I can use to precisely trim, debur, chamfer and clean primer pockets on. Currently Brass prep consumes about 80% of my time at the bench. The other 20 is mostly weighing every charge.

I shoot and load far too many cases now to pheasibly continue to trim, debur and chamfer manually.

Any advise is much appreciated.
 
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Might depend on how "precise" you want. Some (some as in there may be one's that don't?) high speed trimmers depend on case shoulder for finished length. Some powered trimmers like RCBS trim to the actual case length.
 
To me, the Lyman case prep center works great and can run the Lee case trim tools. Best for straight wall.

It is best to trim with a drill, IME. I use the Trim-It ii when doing high volume(400 plus) bottleneck cases.

For precision, I use the Wilson tool. It is precise and a little slow, but I’m doing 200 or less on rare occasion.
 
my homegrown case prep center. Each Wilson was bought used and is set for a specific cartridge. Once adjusted it does not change. I buy them used at gun shows and E bay. The pocket tools came from a Lyman hand cranked set, and are used with a cordless drill, the paperclip stuck to the magnet is for inside case checking. For bulk AR fodder I use a WFT I bought used

Like me it ain't pretty but it gets the job done
 

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I swage my own .40 JHP's out of junk 9mm brass. I recently went through months of trial & error in finding a fast way to reliably cut down the 9mm brass.

My solution was the power mandrel adapter for my Lyman universal case trimmer allowing me to use a power drill instead of the hand crank supplied.

This added to my speed and the uniformity of cut on the brass. So 2 good outcomes for the price of one.
 

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The trimmers made by Giraud, including both their self-powered unit and their drill-powered unit, are examples of trimmers that register bottleneck cases on their shoulders. If your case shoulders are not a uniform distance from their heads, this will result in cases that are different in length by the amount of that head-to-shoulder difference. However, because it registers on the shoulder, this type of trimmer keeps the neck lengths uniform. Because the case shoulder is pushed against the chamber shoulder during firing, if you are trimming to control how close the mouth of the neck can get to the chamber throat (the usual reason given for trimming), then the shoulder registration actually does that more consistently than overall case length does.

One advantage to the Giraud trimmers, in addition to being shoulder registered, is they also chamfer and deburr the case at the same time as they shorten it. The Gracey motorized trimmer will do that, too. The Little Crow WFT and the Possum Hollow trimmers are also shoulder-registering trimmers but do not chamfer and deburr. Anyone looking for quick brass prep will prefer getting three chores done at once.
 
If your case shoulders are not a uniform distance from their heads, this will result in cases that are different in length by the amount of that head-to-shoulder difference. However, because it registers on the shoulder, this type of trimmer keeps the neck lengths uniform
Click to expand...

Sorry Nick, but that is not logical

On drawings SAMMI gives the case length measurement from case head to case mouth. When you measure a case at home to determine if it needs trimmed you measure from case head to case mouth. Any case trimmed to 2.400 is the same length regardless of where the cut was indexed from, the same .XXX length of brass is removed by the cutter
 
Perhaps I was not clear. What I mean is that if you are using a case trimmer that registers on the shoulder and your cases have shoulders different distances from their heads, such as the sizing variations you see when sizing mixed brass or brass fired in different chambers, the trimmer will deliver trimmed cases that are different in head-to-mouth length by the same differences there were in the distances from the heads to the shoulders. Since the length of the neck is between the shoulder and the cutter, the neck length itself will be maintained by shoulder registration trimmers. There is no other possible outcome. SAAMI has nothing to do with it. It is constrained to be true by the geometry of the situation.

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My tools

There is a Forster Power Trim tool I like. It attaches onto a small drill press (Harbor Freight) and you set you length and cut downward. I once needed 7.7 Arisaka cases. After picking up a 50cal can of military 30-06 brass and resizing and cutting them to the approximate length, I used this power trimmer to finish off all the brass. Now I have a 50 cal. can full of 7.7 Arisaka cases.
 
I use a Lyman prep center and really like it. Adapters for large and small primer pockets, chamfer, debur, everything sit on a horizontal plane making clean up a snap. Plenty of power.

Snagged mine for around $120 a few years ago. Price looks like it just keeps going up. Good product/
 
edited when I saw the light

Ok Nick I see where you are coming from. Never occured to me because I only trim and chamfer after full length sizing the cases. As long as my case head to case shoulder measurements are consistent it is a non issue. Now if I were only neck sizing without body sizing then the Giraud would be the better choice.
 
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The "control point" for a shoulder registering case trimmer is from a point on the shoulder. When inserting the case into the cutter, it stops on that shoulder point. If the length from the case head to the shoulder differs on separate cases, the case's length differ the same amount.

The "control point" for a lathe type is the case head, usually semi locked into place.

Yes, they both trim the case mouth. The lathe type can hold a slight edge in precision for oal, while the shoulder type can hold a slight edge in precision for the just the case neck length. Discuss all you want to, the FACTS will not change.

After all the years of trimming brass finally bought a Giraud for retirement. The difference in time spent trimming large lots of brass is just incredible.
 
Yep. If you examine the SAAMI drawings for standard cases and chambers, you see the chamber neck length is specified to be greater than the case neck maximum, usually by ten to twenty thousandths. This is how they handle head-to-shoulder sizing variation and neck length variation. Normally it is not a functional issue.

The shoulder registration trimmers are mainly for the speed advantage of not having to put the case in a holder and of easy adaption to power trimming. Our Giraud trimmers and the other simultaneous trim and chamfer tools have one quirk manual chamfering and deburring don't produce: when you have a case with uneven neck wall thickness or one that your sizing die expander has pulled off-center, the chamfering and deburring cuts are off-center, too. I don't know of any functional drawback to that, either, but it does provide a sort of visual quick check for which of your cases is going to produce the best bullet centering in the chamber.
 
All in all I still think using the case head for indexing is the more accurate way. If the shoulders are not the same distance from the case heads you will end up with a variety of case lengths if you index off the shoulder. But then does anyone interested in precision shooting use neck sizing unless they body size first ?
 
It can be argued either way, but since the seating die puts the bullet ogive a certain distance from the head and not from the shoulder, the amount of jump to the lands will still vary with any difference in shoulder height that is left after resizing.

That shoulder height is really what needs to be controlled for consistency. If we came up with a seating die that fixed the seating depth as a distance from the shoulder to the ogive, that would eliminate the effect of small variations in head-to-shoulder distance on the ogive-to-throat jump during firing. It would also make consistent neck length more important to bullet hold. But we don't have a seating die like that. I made a gauge for measuring that distance for sorting match ammo, but it doesn't make the ammo. And I also don't know if small variations in bullet jump due to shoulder position variations is any more important to consistency on the target than how far the firing pin chases the cartridge into the chamber is. Both will have some effect you can measure with large enough samples, but I don't know which one will be the dominant term.

I frequently wish I had a lab with an indoor range at my disposal, but I don't.
 
I have been using the Frankford arsenal case trim and prep center (platinum). Has all the tooling needed for case prep in one machine. It seems to works well. Trim, debugger inside and out. 4th station can clean primer pockets or remove crimps, or what ever other tooling you can chuck up into the drive.

advantage - you only handle the brass once start to finish.

disadvantage? - it is registering trim length off the shoulder. I put the ? in because I have noticed some inconsistency in OAL as measured from head to mouth with calipers. not by much but enough to notice. Example, if I try to set my .308 cases to trim to 2.005 I will find some as short as 2.004 and as long as 2.007. All within tolerances, but not super consistent. I am not crimping my bullets to a grove, and if I was I think it would still hit the mark. my OCD just notices the dissimilarity if measured.

Fastest trim I have found is the Lyman E-zee trim in a Dewalt drill or drill press. You will still need to debugger the case mouth. As measured with my caliper very consistent OAL as the mandrel is the same length every time.
 
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I think you would have to be using brass sized with different settings to notice much of a difference. My feeling is that with my system it is a bit less expensive and but it takes a tad longer
 
https://youtu.be/FKWpmShM4yY

In this video is a Henderson Precision trimmer. Might be just what you need. It trims, chamfer and debit in 1 stroke. If I was working hundreds of rounds a week I would have one. The host is showing his entire process for reloading. The trimmer is right at 7:00 minutes in.
 
That will register off the head. My only argument with the idea is you are back to holding the case with a chuck, which you get out of with shoulder registration. I like avoiding the head chuck because, shooting gas guns, I get enough extractor burrs and slightly out-of-square case heads that I don't trust it would produce a consistent result for me. As I mentioned previously, I can't see any substantial advantage to either system when the final say in bullet jump still depends on consistent head-to-shoulder dimensions controlled by resizing and not by trimming. If you have that consistent head-to-shoulder number the shoulder registration and head registration trimmers will both produce the same case overall case length and the same neck length.
 
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