How Short or Long for .223?

Unless you're shooting a benchrest gun capable of groups well under a half-inch, it's doubtful you'll see any difference in accuracy using brass that is not all trimmed to the same length.

I have yet to trim my Starline 6.5CM brass, simply because all of it is under the trim-to length and I don't want to trim to the shortest brass length.

Shot three consecutive groups at 100y, just chrono'ing to see how my shiny new Chargemaster was doing. Center-to-center, groups measured .355", .442", and .473". All three had an ES of 15 fps, and SD of either 6.3 or 6.5.
 
So the brass is sized and I have a big pile of brass over 1.75 that I am going to trim. I do not see myself loading these more than twice. I don't shoot enough to go through several thousands of rounds but I just really don't want to get screwed during the next panic. Once they're all trimmed I'm going to load a few and see how it goes. I am very meticulous about measuring charges and COAL. If the few I make work as intended, I'll start to load up some .223.
 
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So the brass is sized and I have a big pile of brass over 1.75 that I am going to trim. I do not see myself loading these more than twice. I don't shoot enough to go through several thousands of rounds but I just really don't want to get screwed during the next panic. Once they're all trimmed I'm going to load a few and see how it goes. I am very meticulous about measuring charges and COAL. If the few I make work as intended, I'll start to load up some .223.

I'm with ya. That is almost my exact thinking as well. Though I may start with a batch of 250 or so and shoot and reload them multiple times, just to see how many firings I can get out of them before they are kaput. I figure can always trim another batch of 250 when the first batch is worn out or depleted due to losses.

After the last shortage I don't EVER plan to get caught shorthanded again. Like the saying goes...

"Having ammo will get you through a shortage of money better than having money will get you through a shortage of ammo." ;)
 
So the brass is sized and I have a big pile of brass over 1.75 that I am going to trim. I do not see myself loading these more than twice. I don't shoot enough to go through several thousands of rounds but I just really don't want to get screwed during the next panic. Once they're all trimmed I'm going to load a few and see how it goes. I am very meticulous about measuring charges and COAL. If the few I make work as intended, I'll start to load up some .223.

Over 1.75" is fine as long as they are no more than 1.76".
 
IMHO This little gadget was my greatest investment for reloading .223.

[ame="https://www.amazon.com/Worlds-Finest-Trimmer-223-Rem/dp/B009NKJXFQ?psc=1&SubscriptionId=AKIAILSHYYTFIVPWUY6Q&tag=duckduckgo-d-20&linkCode=xm2&camp=2025&creative=165953&creativeASIN=B009NKJXFQ"]Amazon.com : Worlds Finest Trimmer 223 Rem : Gunsmithing Tools And Accessories : Sports & Outdoors[/ame]
 
Someone sent me a link to a similar device. I have a question.

This style trimmer measures from the shoulder of the case. How does that get you an accurate and in-spec OAL since it doesn't measure from the case head? How do you know that the head to shoulder length is exactly the same and within spec for every case? It seems to me that the main body of the case could easily be stretched (not just the neck) and if that is true, then measuring just the case shoulder to mouth dimension and trimming it based on that measurement isn't going to get the OAL right. It is just going to get the case shoulder to case mouth measurement right.

It isn't just the neck length that is important, is it? Isn't the OVERALL length (from case head to case mouth) at least as important as the case shoulder to case mouth length?

What am I missing here?
 
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I gage everything after I size. If it's >1.76 I trim it to 1.75. Very common approach and recommended by the Hornady manual.

There are no minimum lengths prescribed. <1.70 would be my toss it test.

Get a good gauge and you can eyeball it with some experience. Zippidy quick.

Just trimmed about 400 cases.
 
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It isn't just the neck length that is important, is it? Isn't the OVERALL length (from case head to case mouth) at least as important as the case shoulder to case mouth length?

What am I missing here?
I size first, check each piece with a Lyman case gauge, and then trim. The trimmer is basically a Sammi spec chamber with a spinning cutter. The critical dimension is the shoulder set back. If the brass is sized to spec it will all be trimmed to the correct length.

My experience is that it will trim to a OAL of +/-0.001
 
Someone sent me a link to a similar device. I have a question.

This style trimmer measures from the shoulder of the case. How does that get you an accurate and in-spec OAL since it doesn't measure from the case head? How do you know that the head to shoulder length is exactly the same and within spec for every case? It seems to me that the main body of the case could easily be stretched (not just the neck) and if that is true, then measuring just the case shoulder to mouth dimension and trimming it based on that measurement isn't going to get the OAL right. It is just going to get the case shoulder to case mouth measurement right.

It isn't just the neck length that is important, is it? Isn't the OVERALL length (from case head to case mouth) at least as important as the case shoulder to case mouth length?

What am I missing here?

I have one, BC. They do work well and work fast. Now, as to your questions:

First, this trimmer only works with fully resized cases. It will not work with cases that have been neck sized only, as a fired case will be expanded too much to fit inside the trimmer body, much like the case holders for a Wilson case trimmer. And with full length resizing, you bump the case shoulder back to around the original measured length of it when new. And that should give you a uniform length for all your resized brass. And that gives you a standardized length for the trimmer to work with for case trimming.
 
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