Trimming case ?

[BULLET 05]

Reloading for a .243 how many times on average would the cases need trimming? Do I need to check after every reload? Or on average after 3-4 times reloaded?

 

[Rsadams]

I check every reload.. Only adds a few minutes , but you know we're they are at..

 

[Capt. Oblivious]

243 grows like wildgrass, check them to make sure and avoid any problems.

 

[SheepDog]

I run all my cases through the trimmer after sizing. It takes less time for me to put it in the trimmer to see if it trims than it does to check them with calipers and trim the ones that need it. I keep them trimmed to about .002 to .003" shorter than the chamber length.

 

[Toejoe12]

I run all my cases through the trimmer after sizing. It takes less time for me to put it in the trimmer to see if it trims than it does to check them with calipers and trim the ones that need it. I keep them trimmed to about .002 to .003" shorter than the chamber length.

+ 1 Exact reason I bought the Giraud......quicker to run through that trimer than measure

 

[Zero333]

Let it grow to within 0.010" of the chamber neck length.

http://bulletin.accurateshooter.com...-chamber-length-with-home-made-modified-case/

My 243win chambers allow me to grow the brass to 2.065" (0.020" longer than saami) before I have to trim them, giving me 0.010" safety room to spare.

 

[Intheshop]

.005" minimum,.010" max here off measured chamber.Write your numbers down,check,test,....report back.

 

[justinp61]

This may be a silly question. How do I measure my chamber?

 

[Ron Blain]

This may be a silly question. How do I measure my chamber?

You can make a chamber casting. Depending on which characteristic or dimension you are interested in you can also use chamber headspace gauges to check your chamber's headspace dimension. So it really depends on which chamber dimension you want to measure.

Ron

 

[Intheshop]

This may be a silly question. How do I measure my chamber?

Look up at Zero333 link.This is how I do it,make a gage on a lathe.

 

[Brians356]

This may be a silly question. How do I measure my chamber?

That depends on what dimension of the chamber you want to measure. For trimming case lengths, the critical dimension is "chamber length" (to the end of the neck portion, where the freebore starts). I.e. how long can a case safely grow before it runs into the end of the chamber? A Sinclair Chamber Length Gage is an inexpensive and accurate way, plus it will leave you a "dummy" case for future reference (in case you misplace the recorded measurement.)

http://www.sinclairintl.com/reloadi...s/sinclair-chamber-length-gage-prod32925.aspx

Or, if you have a Hornady "Headspace [sic] Gauge", you can use a modified fired 22 WMR (22 Magnum) case with your 243 Win modified case, to measure chamber length, as described in this post (6mm Rem illustrated, but it will work the same for your 243 Win):

http://forum.accurateshooter.com/threads/headspace-gauge.3875237/#post-36585857


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[justinp61]

Thanks guys. Last week I was bored and measured some of my 260 (hunting rifle) brass and some of it was long so I was interested in this thread. I have a Forster trimmer that was in a bunch of loading stuff purchased years ago but it didn't have the pilots needed. E-bay to the rescue, they were in the mail yesterday.

I'll order the Sinclare gauges needed.

Sorry if I derailed the post.

 

[Brians356]

From my perspective it's unfortunate that new unfired cases arrive cut to, or even well under, SAAMI "trim-to" length. It would please me if they were cut right at "maximum" case length, since virtually every chamber sports a generous safety margin beyond that length for obvious reasons. Nosler even cuts their 223 Rem cases below "minimum" length, a full 0.025" shorter than "max". Sad!
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[amlevin]

From my perspective it's unfortunate that new unfired cases arrive cut to, or even well under, SAAMI "trim-to" length. It would please me if they were cut right at "maximum" case length, since virtually every chamber sports a generous safety margin beyond that length for obvious reasons. Nosler even cuts their 223 Rem cases below "minimum" length, a full 0.025" shorter than "max". Sad!
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Just remember, if the factory turned out cases longer than the SAAMI minimum that would be more brass in every case. Multiply that by the millions of pieces they produce every year and that extra .010" would cut into their profits

I just set my trimmer to the length I want and eventually all my cases start getting cut to that length. Some just take a little more "hammering".