Retrimming after trimming .223 to 1.750?

[M1ke10191]

I just posted a response to a post about someone not trimming his .223. I tried that once and locked up my action once the round fired.

I use a WFT and trim the brass to 1.750 +/- .001". My question is what are the odds of that brass stretching enough to require trimming before the case itself wears out? Is it "trim-and-forget?"

I know I should be measuring it every time per reload but practically speaking, what has been your guys' experience?

I don't have X dies either but I hear they're worth it.

-Mike

[rebs]

I trim once fired LC brass once and it is generally good until the case is worn out.

[temmi]

I trim all cases to "Trim Length" every time.

If you do not want to do that you must measure the Sized case length and trim the ones that are too long

this is a safty issue

Snake

[NWPilgrim]

I find that .223 brass grows about .003" with each resizing. So you could get at least 3 firings/resizes before it needs to be trimmed. A very small percentage of brass is culled each time but most .223 brass will last more than 3-4 firings. I would say 5-8 is more typical, but it depends on several factors such as whether you load to max or excessive pressure, if your chamber diameter is on the large size of tolerances, excess headspace, and how much your die sizes it back down.

Trimming cases is important for safety. I measure each case for every reload cycle. I use an RCBS X-die to stop the case lengthening past the trim length, but I usually get at least a few strays picked up at the range which often have cases exceeding my trim to length of 1.750". So even though there may be only a couple of cases that need trimming, I measure every single empty case to ensure I don't miss them. I have not tossed one case yet for signs of head separation. The majority are case neck splits, and a few were cracks in case walls. With a couple of thousand cases and shooting 200-300 each session I cull maybe a half dozen each cycle.

Pistol cases I just clean and reload. But rifle cases work under much higher pressures so I give them a lot more individual attention.

[M1ke10191]

Right, with pistol cases I don't bother and it's obviously much more pleasant to reload them.

I might start doing what Temmi said and just trim them all regardless. It might be faster to blindly throw them all in my WFT and C/D rather than individually put calipers on every case.

My main reason for asking this is down the road I want to upgrade to a progressive and having to trim rifle rounds severely inhibits that process.

Any thoughts on the X dies and their reliability? Are they worth the cost? I'd only do this for .223; my larger calibers aren't shot enough to warrant the extra cost.

[Brian Pfleuger]

Originally Posted by temmi

this is a safty issue

It's not a safety issue between EVERY use.

I've not yet had to trim a single rifle case twice and I have some with 8-10 full-power loads threw them. In fact, they're not even close to needing trimming again.

I find that the case will grow to a certain point and then pretty much stop. If they don't, you're not sizing them correctly.

Properly sized cases will have very little FORWARD growth and essentially no head stretching.

Improperly sized, incorrectly headspaced cases, will grow BACKWARDS... in other words the head is stretching toward the breach. This leads eventually to head separation and is a safety issue unrelated to trimming.