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trimming to same length

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26 January 2002, 17:36
<robv60>
trimming to same length
Maybe this isnt all too important for the 38 special but I want to be able to trim all my cases to the same length. Presently, I am using dial calipers to measure each new case. My problem is that when i use my calipers to measure a case i get several different readings for one case. Say for instance if i measure a case and get 1.50. Then, i turn the case 1/4 turn and i get a reading of 1.48. Then another turn and 1.52,etc. I have no idea which measurement to follow! I figure this is because the case mouths are not "squared up". Anyway, I thought that I could cut all my cases to the same length using my LEE case length guage and cutter/lock stud trimming system. The problem with this trimmer is that it will only trim if the cases are already over maximum length. No good if you just want to square up the case mouths and trim them all so they will be the same length after firing. (i have read in a couple of manuals that you cannot get consistant crimping on cases if they are not the same length. Which is what i want-uniform crimping for accuracy). Are there any specific tools or techniques that anyone knows of that will enable me to trim all my cases to a uniform length after each firing with out having to put alot of guess work into it?
26 January 2002, 18:08
grizz
robv60, take an abrasive to the pin on the end of the lee pilot. Then trim a few cases. Measure and remove more metal if necessary from the pilot pin. Find the shortest case in the lot of cases and adjust the length of the pilot to just barely square up that case. Then get a new trimmer pilot for when the cases grow and need further trimming.

I have several "sets" like that for my lee trimmer.

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if you run, you just die tired

26 January 2002, 18:12
<robv60>
I had thought about doing that but I am having a problem using my calipers. I keep getting different readings, will squaring up the case mouths solve that?
26 January 2002, 19:18
Mark
If the problem is the case mouths, yes. However if the problem is in the calipers then no it won't. Are your calipers metal or plastic? Also, how are you using the Lee trimmer, by hand or in a drill press? Like Grizz, I'd suggest taking a swipe or two on a sharpening stone to take a little off the pin of the trimmer. 38's headspace on the rim so it is not really an issue either way, you can use the cases as is if you want, or shorten them....

Try measuring a different case.

Oh, this just occurred to me- make 4 marks with a scribe or sharpie marker on a case, then measure it 3 or so times on each mark. If the case is the problem then the measurements will be different between the groups but consistent in each grouping (where it was marked). If the caliper is bad then there will be no consistency in either of the individual or the total groupings.

26 January 2002, 19:34
<robv60>
I actually tried something of the sort by measureing the diameter of several,i.e. 20 of my bullets. They all had consistant measurements of .357. So i dont think it is the calipers. My Calipers are stainless steel.
27 January 2002, 02:49
<stans>
I have found that most pistol brass have variations in case length. For plinking loads, this is not a problem. If you are going for bullseye match loads, trim them to the shortest measured length in that particular lot of brass. Brass with consistent length will yield consistent crimps which gives more uniform ballistics.

[This message has been edited by stans (edited 01-27-2002).]

30 January 2002, 02:45
243winxb
A taper crimp die is made just for cases like these. Only the roll crimp die gives u problems when cases are all different lengths.
30 January 2002, 12:14
raamw
A trick I use is I resize one case for each casing that I reload, I then trim it to the specification lenght, I then put a red tape on this cartridge and use the to adjust my case trimmer. Case lenght is important especially if you want the bullet crimped, a longer case get deformed. On the cases that I crimp I have purchased Lee crimping die which prevents any problems that start with cases that are not all the same lenght. These dies run about $8.00 each at the various discount reloading supply houses loke Midway or Midsouth Shooters supply.
30 January 2002, 14:00
Atkinson
Trimmers are just not all that accurate, they can be about 2or 3 thousands off every time...but hey, so can a lathe...no big deal, thats close enough for hair splitting.

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Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com