Need some advice on trimming .38 Special brass

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I generally don't trim pistol brass and have gotten moderately successful results with .38s and .357s using mixed range brass and just setting the crimp for the longest cases. However for WC loads seated flush this will obviously not be ideal. So I'm resolved to trim my entire stash to the shortest common denominator. Trouble is almost all of my brass is below the minimum recommended trim length, even a lot of factory once fired. hornady says trim to 1.145" (max 1.155"), Lyman says trim to 1.149". The majority of my brass at least of the couple dozen I measured is below 1.144", with some as short as 1.137".

Some GI once fired is 1.150" but that's the longest I've found.

So: options? I REALLY don't want to measure every case and I'm not going to. Should I give up? Should I just seat my WCs to the crimp groove and proceed as I have been?

I really don't care enough about this to individually measure and categorize a couple thousand cases.

Downsides to trimming them all to 1.137 or maybe 1.140"?
 
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You’re supposed to measure the brass once it’s been sized. They grow a little during the sizing process.

I’d find the most common headstamp of your brass and start with 50, or 100 or however many you’ve got and see how uniform they are. I’d just toss any outliers and proceed without trimming the rest of the batch.
 
I generally don't trim pistol brass and have gotten moderately successful results with .38s and .357s using mixed range brass and just setting the crimp for the longest cases. However for WC loads seated flush this will obviously not be ideal. So I'm resolved to trim my entire stash to the shortest common denominator. Trouble is almost all of my brass is below the minimum recommended trim length, even a lot of factory once fired. hornady says trim to 1.45" (max 1.55"), Lyman says trim to 1.49". The majority of my brass at least of the couple dozen I measured is below 1.44", with some as short as 1.37".

Some GI once fired is 1.50" but that's the longest I've found.

So: options? I REALLY don't want to measure every case and I'm not going to. Should I give up? Should I just seat my WCs to the crimp groove and proceed as I have been?

I really don't care enough about this to individually measure and categorize a couple thousand cases.

Downsides to trimming them all to 1.37 or maybe 1.40"?
FWIW, SAAMI specs for 38 Spl. case length is 1.155", +0 / -.020". That would make 1.135" the minimal for case length per SAAMI. Just a FYI. :)
 
I generally don't trim pistol brass and have gotten moderately successful results with .38s and .357s using mixed range brass and just setting the crimp for the longest cases. However for WC loads seated flush this will obviously not be ideal. So I'm resolved to trim my entire stash to the shortest common denominator. Trouble is almost all of my brass is below the minimum recommended trim length, even a lot of factory once fired. hornady says trim to 1.45" (max 1.55"), Lyman says trim to 1.49". The majority of my brass at least of the couple dozen I measured is below 1.44", with some as short as 1.37".

Some GI once fired is 1.50" but that's the longest I've found.

So: options? I REALLY don't want to measure every case and I'm not going to. Should I give up? Should I just seat my WCs to the crimp groove and proceed as I have been?

I really don't care enough about this to individually measure and categorize a couple thousand cases.

Downsides to trimming them all to 1.37 or maybe 1.40"?

Only downside to trimming them is putting in a lot of time trimming a couple thousand rounds. A shorter case will increase the pressure slightly, but that amount of difference on a wadcutter load shouldn’t matter that much. If you were loading 200 grain bullets to +P levels in an old pistol I might worry just a little, but not with WCs.

You’re supposed to measure the brass once it’s been sized. They grow a little during the sizing process.

I thought straightwalled brass shrinks with repeated resizing. All my .38 Special has gotten a little shorter over time.
 
FWIW, SAAMI specs for 38 Spl. case length is 1.155", +0 / -.020". That would make 1.135" the minimal for case length per SAAMI. Just a FYI.
Really?? Thank you! I assumed it was a range of .010. Maybe I'm okay to trim to 1.137" then?
 
I have some old 38spl brass and the case lengths after sizing were close enough. With newer brass the case lengths are all over the place.
My guess is that the method of crimping has changed and does not require a consistent case length.
I use a Lee collet crimp for plated bullets in 357 mag and 44 mag and case length variations are not a issue.
When I need to crimp to a cannelure or crimp groove I want the brass to be a similar length, if the short brass is 1.145" and the long brass is 1.153" I trim it all to 1.147" if the short cases have a out of square mouth I save them for a shorter batch.
I've noticed a lot of revolver brass is way out square, so when measuring you need to be aware of this.
 
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Really?? Thank you! I assumed it was a range of .010. Maybe I'm okay to trim to 1.137" then?
Most revolver case specs are +0/-.020", since the rim is the setting depth point in the chamber. Semi-autos are mostly, if not all +0/-.010", since the case mouth is the setting depth point in the chamber.

If it were me, I would only trim back enough for what I'd load WCs in. And keep those segregated from the rest of the 38 spl. brass. Otherwise, you might find yourself short to roll crimp for a certain bullet per a published load.
 
I'd set my trimmer to 1.142" and trim all the brass that you want to devote to wadcutters. Those 1.137" cases will be fine if they get lumped in with the ones that actually get trimmed.
 
I have some old 38spl brass and the case lengths after sizing were close enough. With newer brass the case lengths are all over the place.
My guess is that the method of crimping has changed and does not require a consistent case length.
I use a Lee collet crimp for plated bullets in 357 mag and 44 mag and case length variations are not a issue.
When I need to crimp to a cannelure or crimp groove I want the brass to be a similar length, if the short brass is 1.145" and the long brass is 1.153" I trim it all to 1.147" if the short cases have a out of square mouth I save them for a shorter batch.
I've noticed a lot of revolver brass is way out square, so when measuring you need to be aware of this.
Yeah I've noticed that too. Visibly not square on the case mouth. by the way I measured some before and after sizing and the gentleman above is correct; they grow about 35-50 TEN thousandths after sizing. Interesting.
 
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Since I have to handle each case for trimming I figured it wasn't much more of a pain to sort them into 4 groups; my three largest populations are R-P, Winchester, and S&B. I'm putting all nickel/GI/GFL/Federal/other in a fourth bucket for now. I dunno... gives me something to do I guess.
 
I'd just find one of your shorter cases, seat so it's perfect for that one, then let the rest just poke out a tad. Unless you're shooting ultra competitive, the relatively short ranges a 38 wadcutter for shouldn't be much affected by the tiny variation s in length. Heck, I've reloaded the Hornady 357 cases that are way too short with fair success.
 
Trim them to an average 1.140 and don't worry about the ones already at 1.137. That's what I did back when I trimmed a bunch that I am still using. Same reason, so many near 1.140 with plenty longer than that (1.145 to 1.150 and a few oddballs here and there)

A .005 spread won't hurt you. At about a .010 spread you start to see differences in crimp. Good news is at light .38 Spl target load pressures it's a one and done move.
 
I am confused. You say you want to seat them "flush" but then say "should I just seat them to the crimp groove"?

What bullet are you using.?
 
When I first started reloading I trimmed straight wall pistol cases. It stands to reason that the same length cases would have equal crimps and should shoot better. Well, I discovered that me and my equipment are not good enough to see the difference!

When I did trim pistol cases I did it after resizing. I trimmed them about .001 shorter than the shortest case.
 
I trim fired, unsized brass to 1.140 +-.002, expecting it to be somewhere about 1.145 or so after sizing. I don't want to load sized brass, because the press needs the resistance at sizing to balance the bullet seating station. Simply check length of a few of whatever case is in question before and after sizing and factor that difference for the unsized case target length. I don't think greater precision than that would ever be necessary for a revolver unless obsessive about target match ammo. I do actually measure everything, but only before being put away after cleaning, never thousands at a time. Think chewable bites.

I segregate length classes as [1.135 +.002-.000], [1.140 +-.003], and [1.145 +.000-.002]. Whether functionally necessary or not, that's what I do as a matter of craft. I trim anything over 1.147

I agree about measuring and trimming only a batch to be used for WC. If you mark the heads with a permanent marker, you won't have any problem sorting them out of a mixed batch of fired brass. I don't size new brass, so it is treated the same as fired and will be filtered for trimming by measuring everything after cleaning. Most of my 38 brass that is cleaned comes from a cowboy action match, so there could be someone else's brass in the batch, teaching me to measure everything but never more than a hundred or so at a time. I also segregate head stamps.
 
I have never trimmed a 38 brass in 35 years. I have several thousand of them and I am not starting now. Unless you are loading for something finicky like a S&W 52, I wouldn't worry about it. JMO, YMMV.

I only get concerned about cracks and splits.
 
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