5.56 case?

[stoney1666]

i know they should be 1.760, but can they be a little longer? got about 300 cases that are 1.768 to 1.770 and if i don't have to shorten them that would be great. doing the primer pockets is another story.

 

[CoalCrackerAl]

They should be trimmed to at least 1.750. Factory brass is not longer than 1.750.

 

[N555]

Nope, time to buy a trimmer.

 

[243winxb]

Measure trim length after full length sizing.
Chambers can run as much as .010" longer then maximum trim length. I call it the " Safety Zone". This extra room keeps rounds from getting " Crimped" while chambered. A fired crimped round will raise pressures to a dangerous level.

Its possible to measure the exact chamber length & allow brass to be longer then SAAMI maximum. NOT RECOMMENDED.

https://www.brownells.com/reloading...s/sinclair-chamber-length-gage-prod32925.aspx

The differences between published trim lengths and the actual length of your chamber can be quite significant. You could be over trimming your cases by .030 inch or more

 

[243winxb]

Poor man's way to measure chamber length.https://bulletin.accurateshooter.co...-chamber-length-with-home-made-modified-case/

I did it a little differently, to my single shot Rem 40X.

 

[Walkalong]

got about 300 cases that are 1.768 to 1.770 and if i don't have to shorten them that would be great.

That would be great, but it's time to bite the bullet and trim cases, no need to push fate with sloppy reloading.

 

[lightman]

Another vote to trim them. Most of us hate trimming brass but its part of the process!

 

[Blue68f100]

If you have a bunch to do, the drill press mounted 3 way trimmers are the way to go. Once setup, you can trim faster than you can measure the brass. So you just run them all through and be done. The ones that need it get trimmed the others don't.

Just remember these measure off of the shoulder not the base. So the more consistent your sizing is the more consistent the trim length.

 

[Walkalong]

The easy button

https://www.littlecrowgunworks.com/store1/223-Remington-Case-Trimmer-p117183975

 

[film495]

did you measure after sizing? size and measure and see if they are in spec. don't know if it is recommended, but I'd think you could make a few dummy rounds with the longer ones and see if the chamber and plunk correctly. chambers vary, you never know, might be fine for your chamber, but again no idea if that is a good idea or a safe one.

 

[Skeptic13]

1.760 is the max length according to the SAAMI spec. Longer than that and you run the risk that the cartridge won't chamber. The trim length is 1.750. I normally don't trim anything under 1.755 and have never had an issue. I usually trim a little longer to 1.753 and have found that after the first trim and reload I don't have to trim as many the second time.

 

[Bronco72]

I knew a feller once that brought his rifle home in pieces because he did not trim the cases. Granted I do not remember how many times he said reloaded the cases before it ka-boom. I think around 3. Luckily he was only stung by the incident!
I have always trimmed bottle neck cases and since then I don't even think about skipping that step.
I would trim the cases!!
I just sayin.

 

[Nature Boy]

If you have a bore scope you can come in from the muzzle and see exactly where the end of your case falls in your chamber. This is one of my .308s



Otherwise, just trim it when it exceeds the recommended case length. It’s a lot easier

 

[Rule3]

did you measure after sizing? size and measure and see if they are in spec. don't know if it is recommended, but I'd think you could make a few dummy rounds with the longer ones and see if the chamber and plunk correctly. chambers vary, you never know, might be fine for your chamber, but again no idea if that is a good idea or a safe one.

Yep you need to size them first, they may get longer!

 

[bdb242]

Re-size full length, clean, tumble, or whatever you do to shine it up and re-measure. Trim if over 1.760 to 1.750 and shoot several times and check again. My new brass is usually 1.745 from Starline and 1.754 from Lapua. AR or Bolt gun? Chambers are different.

 

[hdwhit]

I trim my 223 brass to 1.753.

Once I adopted this length - following a lengthy process of trial-and-error with the five rifles for which I load - everything was fine.

Trim-length, Shoulder set-back, etc., are set by SAAMI. If they don't work for you, then carefully evaluate what you are doing. You may need a different trim-length, but first investigate WHY you are departing from industry standards.

 

[Walkalong]

I trim to 1.750, just because it's the recommended trim length.

 

[Coyote conquest]

Just buy a trimmer. You can get a cheap lee or WCT off eBay if needed but I would trim.