better way to measure case length?

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westernrover

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I use a Brown & Sharpe dial caliper to sort cases for trimming. I don't trim often, but I gauged about 1000 cases with the calipers a week ago and my thumb is still bruised from pushing on the calipers. Is there a better way to measure and sort a large batch of cases?
 
Yes, dial caliper here as well. I do loads in batches. If I have more than a couple that do not pass my caliper as a go/no-go I generally run them all through the trimmer. If they need it they'll get it, if they don't nothing will get trimmed.

-Jeff
 
I just trim it all to the same length and let it go. With the cases I do trim they are ejected into my hand and put in my bag. New range pickups go in a plastic ziplock and are kept separate so I dont have to deal with big volumes again.
 
How would you find cases that are too short with that method? -- if a case is 2 or 3 thou short?
 
westernrover said:
How would you find cases that are too short with that method? -- if a case is 2 or 3 thou short?
Click to expand...
Honestly are we shooting at that level. If we are then we measure each one. 6br cases are handled with loving care and every aspect is checked with each step. 38 cases for fun are trimmed as described. I dont treat all ammo the same not even close.
 
Ironicaintit said:
I use dial calipers too, but I set it to whatever dimension I'm looking for, tighten the knurled set screw to lock it in place and use it as a "go-no go" gauge.
Click to expand...

Yup; If you are using a trim die, you don't need to do any measuring. Just screw it down snug, and run the cases up into it; file off anything that sticks up, chamfer and bevel. Next!

If they don't reach the top? set them aside, and go through them later, or just toss 'em in the scrap bucket.
 
I made my own "go-no-go" gauges. Any that do not fit the gauge get trimmed.

It depends on the cartridge, but usually out of a batch, only about 25% need trimming.

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As said by others, you can set a caliper to do the same thing by locking the jaws at the max length you want before you trim.
 
If a case is only a couple thousands short, I load it as normal. I ain't lookin for perfect accuracy though. If it's a bottleneck rifle cartridge it'll likely be .003 longer after the next firing. Now, .010 short is a different story if it's getting crimped.
 
I'm using a Wilson trimmer and it's easier to check them with the calipers than it is to load them in the trimmer and give it a try with the cutter head. I use my calipers to sort three piles - trim, no trim, and too short. That way I'm only loading less than 1/3rd into the litle trimming lathe.

I will try locking my calipers to find the long cases. Then I suppose I would have to lock it two thou under my spec to sort the ones that are in spec from the ones that are short.
 
barnfrog said:
You could go through them twice if you're that concerned. Set the caliper for max and trim any that are long. Then set it for min and toss any that are short.
Click to expand...
Why would a fella toss a short cartridge? They grow like toenails and why measure a thousand with a caliper before thinking there may be another way, if you rotate the case the caliper will likely give a different reading due uneven trimming unless one uses a Wilson trimmer with a case holder
 
When I was trimming brass, I used an old saying; "How do you eat an elephant? One bite at a time!". I only did as many as I was comfortable with doing at one time. I like reloading, all aspects of reloading, but I can't ever remember processing more than 200-250 or so cases at a time, so no sore thumb. The only process I do more cases at a time is tumbling and then it's as much as I can get im my tumbler. When using a caliper as a gauge, its easy to tell if a case is too short as the slop fit is easily noticed..

But when I was trimming a lot of cases, I used my Lee trimmer kit or a Lyman EZ trim. No adjustment and using a hand drill. Went fast and easy and only checked length every 8-10th case (most of the time there was less than .003" variation)...
 
westernrover said:
I use a Brown & Sharpe dial caliper to sort cases for trimming. I don't trim often, but I gauged about 1000 cases with the calipers a week ago and my thumb is still bruised from pushing on the calipers. Is there a better way to measure and sort a large batch of cases?
Click to expand...
You could use a case gage. I have a LE Wilson .308 gage and a JP enterprises .308 case gage. The JP gage is cut to saami min spec so it will quickly measure all critical dimensions of the case and let you know if something is wrong. This is good for me since I'm mostly using lake city machine gun brass and loading ammunition that needs to function in several different semi-auto 7.62 rifles. Basically if it fits that gage, it will fit most any rifle of that caliber. Both gages, of course, have steps cut into them that let you know if you're too long and need to trim. I don't mind measuring though so I measure them all and use the JP gage to check the base of the case on this brass that is kind of beat up by a MG. I trim with a Giraud triway cutter which is pretty slick. I have it chucked into a drill press right there on my loading bench and once you set it, you could trim every piece of brass without measuring it first and it would only trim the ones that need it since it indexes off of the shoulder. If you set it to trim brass to 2.005" and you put a piece in that's 2.004" (which seems unlikely unless you forgot to resize a piece), it won't trim it. If it's 2.006" or more, it will trim it. I haven't played with the Giraud triway in a while so I just trimmed 8 pieces of 7.62 lake city brass that I sized last night. It takes about 5 seconds to trim a case to length with this device and, at the same time it's trimming, it also chamfers and deburrs the mouth-each one exactly the same as the last one. I measured everything before and after. Cases were all between 2.017"-2.021" before trimming. they all trimmed up to 2.005" except the first one that trimmed to 2.008. I thought I had set it at 2.008" but the next piece was 2.005" so I realized I hadn't so I trimmed it again briefly and got 2.005". That happens sometimes with this case trimmer. So, if I hadn't been measuring these cases after trimming, I would have ended up with 1 case out of 8 that was .003" out of spec. Big deal. and they all looked passable in my case gages so there's that too.
 
South Prairie Jim said:
Why would a fella toss a short cartridge? They grow like toenails and why measure a thousand with a caliper before thinking there may be another way, if you rotate the case the caliper will likely give a different reading due uneven trimming unless one uses a Wilson trimmer with a case holder
Click to expand...

I find that my intermediate rifle and revolver cases do not grow in length. The get shorter and that is without trimming them.

Yes. I use a Wilson. I want my mouths square.

Yes. I will also turn the case while it's in the caliper to verify it is square and one edge of the mouth is not higher than the another. Before I started using the Wilson, I saw more of this. Now the mouths are consistent within a half-thou. I still slip the mouth and rim in the calipers a little because sometimes there is a raised edge on the head or rim. As more of my brass gets sorted, I see less of this too.
 
westernrover said:
I find that my intermediate rifle and revolver cases do not grow in length. The get shorter and that is without trimming them.

Yes. I use a Wilson. I want my mouths square.

Yes. I will also turn the case while it's in the caliper to verify it is square and one edge of the mouth is not higher than the another. Before I started using the Wilson, I saw more of this. Now the mouths are consistent within a half-thou. I still slip the mouth and rim in the calipers a little because sometimes there is a raised edge on the head or rim. As more of my brass gets sorted, I see less of this too.
Click to expand...
What is an intermediate rifle ? Forgive me I’m stupid..
 
cfullgraf said:
I made my own "go-no-go" gauges. Any that do not fit the gauge get trimmed.

It depends on the cartridge, but usually out of a batch, only about 25% need trimming.

index.php


As said by others, you can set a caliper to do the same thing by locking the jaws at the max length you want before you trim.
Click to expand...

I do the same thing by locking my dial calipers at the size & then pass the brass through the jaws while I'm inspecting them. Killing two tasks at one time.
 
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If I am trimming thousands of cases, I am using a Dillon trimmer on a case fed progressive. Size/decap, trim and expand with a Sinclair push in expander.

I can run 1000 cases through that setup, trimming the ones that need it and doing nothing to those that don’t, quicker than I could pick up 1000 by hand, one at a time, much less measure them.

No sore fingers, at least until you load them all into mags…
 
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