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alexisjohnson
10-09-2016, 1:27 PM
Hey guys,

So when i'm trying to measure the length of my 223 shells, i'm having a bit of a problem. First of all when i use the calipers, most of my military crimped brass measures 1.775 ish. When i place it into the case gauge it shows it as being slightly over the max length.

The strange thing though is when i trim it and measure it... i come up with a length of 1.765 or 1.768 but it fits fine in the case gauge (in between in and max).

What gives? I thought the standard size was 1.760...

Any ideas, suggestions, or insights?
highpower790
10-09-2016, 1:32 PM
1.760 is supposed to be max ,with a minimum of 1.750,but is ok to trim under to as little as 1.740.Are cases being trimmed before or after sizing?brass should be trimmed after...
MarikinaMan
10-09-2016, 2:38 PM
Are you measuring fired shells? Im new to reloading. The cases Im working with, PRVI match, were fired from new ammo by myself. They are all measuring over 1.76. Im trimming them to 1.751 - 1.755 and theyre slowing stretching back, Im on my third firing. If I trimmed to 1.76, Id expect to trim every reload, which I dont want to do.
alexisjohnson
10-09-2016, 2:49 PM
Yeah, i've been measuring once fired brass after resizing.

The ones which i trim to 1.760 show up as being shorter than the minimum in the case gauge i have (dillon) and the ones which i trim to 1.771 show as fitting in between the min and max.
bazineta
10-09-2016, 2:54 PM
Measure the case gauge with your calipers. What does it read?
OpenSightsOnly
10-09-2016, 3:27 PM
Im trimming them to 1.751 - 1.755 and theyre slowing stretching back, Im on my third firing. If I trimmed to 1.76, Id expect to trim every reload, which I dont want to do.

You may want to use a trim length of 1.748" and that may allow you to trim at every other firing.

Or, buy a Giraud Trimmer :)
Abenaki
10-09-2016, 3:30 PM
Im on my third firing. If I trimmed to 1.76, Id expect to trim every reload, which I dont want to do.

I would trim to the minimum.

If you are shooting them in a bolt action, try neck sizing. Or adjust your full length sizing die, so that it will not push the shoulder back as far.

For some thing like an AR, I have no experience.


Take care
Abenaki
TKCastle
10-09-2016, 4:35 PM
Are they decapped? Primer craters add a few thou.
alexisjohnson
10-09-2016, 5:03 PM
Shnaps...that might be it. They have the style of criming that kinda protrudes. That might be what i'm getting
mjmagee67
10-09-2016, 9:12 PM
1.760 is supposed to be max ,with a minimum of 1.750,but is ok to trim under to as little as 1.740.Are cases being trimmed before or after sizing?brass should be trimmed after...

Actually the 223 length is 1.760 -030. So the minimum length and still be in SAMMI specs is 1.730.

http://www.saami.org/PubResources/CC_Drawings/Rifle/223%20Remington.pdf

With that said I trim to 1.740 for auto-loaders (AR's).