Case trim lenghth how critical?

WAREWOLF

WAREWOLF

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Hey everyone

I'm new to reloading and wanted to know if you trim a case to short let's say 38 special which I load often.

The trim length is 1.145. If it is 1.143 or 1.144 is tha a garbage case now or can it be loaded and fired, will it creat problems, or unsafe to use.

Any help would be great.
 
Ishodu is right, that case can be very short if you wish. You could shoot the much shorter 38 S&W round in that chamber without problems. If you're shooting your 38spl in a 357 magnum, all 3 cartridges could be used safely.
 
There's really no point in checking trim lengths on pistol casings.
Pistol casings shrink with multiple firings.
The danger is with rifle casings which grow in the case mouth area.
 
bearhunter said:
Ishodu is right, that case can be very short if you wish. You could shoot the much shorter 38 S&W round in that chamber without problems. If you're shooting your 38spl in a 357 magnum, all 3 cartridges could be used safely.
Click to expand...

.38 S&W is a different cartridge case, and should not fit in the chamber.
For pistol cases, consistent length is more important than short. If you have a few that are short, I would rather throw them than keep in the batch. Unless it is a rare or expensive case, in which case I might trim the whole batch to the same length.
 
Straight wall cases like .45/70, 9mm, .38 spl, .45 ACP etc usually do not grow longer from firing like bottleneck cases (.308 etc) do. Sometimes they even get a bit shorter on their own. For most pistol uses there is no need to trim, even to unify. With some rifle people will trim to get them the same, and with some old style cases people buy case stretchers to lengthen them.

In short I wouldnt worry about trimming pistol cases. And with most straight wall rifle I dont bother either.
 
Straight walled cases don't really flow forward like bottlenecked ones. They don't usually get longer, they just split after 5-25 firings. For bottlenecked rifle it's good practice to trim them every 2-3 firings.
 
Thank's. What about head space for pistol cases will not triming the cases give me headspace or bullet seatting issues?
 
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WAREWOLF said:
Thank's. What about head space for pistol cases will not triming the cases give me headspace or bullet seatting issues?
Click to expand...

How would that happen?

On any of the rimless pistol cases that use the case mouth to space off of(9mm, 45ACP, etc.), length matters. The rest, it's gotta fit into the chamber, there needs to be room for the cylinder to turn (bullets can't be too far out the front), and you need a powder charge appropriate (ie: don't try to stuff the same full charge of powder into a now half-sized case), otherwise there's not much to do other than check for cracked cases and generally go through the motions.

You should spend your time worrying about double-charging cases, if the powder you are using will fit (and esp. if it will fit without being really obvious!), rather than pissing about trimming cases that don't need it.

Guys actually blow up guns from double charges. As risk assesments go, that is the one worth watching for, IMO.

Cheers
Trev
 
Length will make a difference if you are crimping a bullet in a crimp groove on the bullet. Just did a batch of 45-70, some of which were once fired, some multiple reloads, various case manufacturer. Regretted not trimming all to the shortest case length of the group. I have actually never seen so much case length variance in this cartridge as even the multiple fired cases were relatively light loads and exceeded the once fired by nearly 1/10 inch. Should have checked rather than fiddle with seating depth and crimp settings.
 
Ayup, stocker, fair point!

Having them all pretty close to the same length will make setting up a crimp easier. If a crimp is used.

Cheers
Trev
 
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