223/556 trim question

Hello, everyone I know this may be a Dum question. But i recently Bought a batch of Brass 223/556 that was supposed to be good fired brass i mistook the information provided and didn't ask questions as i should have any how its a done deal now.. my question is what is the shortest trim length that would be ok and safe i have reloaded for several years and never ran in to this problem of cases being under trim specs.. and there's a lot that's under 1.750. should i just scrape everything under 1.750 in my experience i get split necks before ever trimming as short as some of these are. 1.69

Thank you and God Bless

JDAS

Short becomes more of a problem with cast. With jacketed it's mostly not an issue.

Yea i hadn't been online much to check it out and seen semi spec is 1.73 after posting this .. i do load 55 grain cast but i now feel a little better.. Thank you M-Tecs

God Bless

JDAS

The shortest trim length I've seen is 1.740" (Accurate Arms data). No issue using ones that short.

The length of 1.690" is on the short side. Max length of 1.760 makes them 70-thousands under. I'd be tempted to either scrap them or use them for light loads until they stretch.

45_Colt

I don't crimp 223/5.56, so they would all be shootable. I would probably separate it at 1.740 amd see how the numbers look. I see no reason someone would trim to 1.69 unless coverting to another caliber.

If only a few under 1.74, I'd consider converting them to 300 HAMR or 300 BLK if appropriate donor cases.

1.730" is SAAMI shortest case length. Normal trim to is 1.750"

https://saami.org/ 223 & 5.56

Cases shorter than SAAMI are not a particular safety problem. MANY, many factory chamberings have neck lengths that are very long compared to SAAMI specs. Accuracy can be affected, with bullet alignment or a slight base upset before the bullet enters the throat causing the loss of accuracy. Until you are getting to the under 1-1.5 MOA, you probably won't notice a difference. Too long can be unsafe, pinching/holding the bullet, too short - maybe, just maybe some loss of accuracy. I measure the chamber length of all my rifles, most lengths are much more than .008 over SAAMI MAXIMUM chamber length. Too long -safety issues, exact chamber length - best accuracy, shorter cases - slightly shorter is the common fit, very short accuracy can be affected, probably not with jacketed, maybe with boolits.

As an factory example Hornadys 45-70 leverlution ammo cases are short by .060 to make the bullet work at overall length. Drives the bpcr boys crazy but its safe

I've bought range brass (223/556) where some was shorter than I like. I sort them out, and load some cheap 55gr FMJ for AR plinking when I can't recover brass.

Short brass could theoretically promote slightly faster throat erosion in high velocity cartridges like 223. If you have a real good shooter, it might be worth buying some OF'd. Lake City is usually pretty cheap, and you know it's OF'd when the pockets are crimped. All of my OF'd LC is slightly longer than SAAMI max.

Stupid suggestion most likely, but do remember to measure AFTER sizing...

I've run into some .223s on the short side, but being a no-crimp or taper crimp guy,
I never thought much about it. I have definite concerns about cases being too long,
but being a little short never hit me as being a problem.

For my old SP-1 AR, everything I load is running along at about 75-80% of max. with Hornady or Sierra
55gr. FMJ "2nds" I buy when I find them on the cheap.

I seat for a tiny bit under max. OAL and live happily ever after.

Quote:

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Originally Posted by jrayborn

Stupid suggestion most likely, but do remember to measure AFTER sizing...

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Yep all measuring is after i full length resized all of them..

Thanks everyone for your input there is multiple brands of cases most being older Lake City .. Like i said in my post it maybe a dumb question but i have never ran in to anything being to short a few here and there that i just scrap and go on but there's hundreds of cases that are under 1.73 1.72 1.71 and 1.69 .. i always use a Lee factory crimp die on all my loads. all measurements are after full length resizing that i did . i in general don't take someone else's word on them being done.

Thank you and God Bless
JDAS

Quote:

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Originally Posted by Jadkins87

Thanks everyone for your input there is multiple brands of cases most being older Lake City .. Like i said in my post it maybe a dumb question but i have never ran in to anything being to short a few here and there that i just scrap and go on but there's hundreds of cases that are under 1.73 1.72 1.71 and 1.69 .. i always use a Lee factory crimp die on all my loads. all measurements are after full length resizing that i did . i in general don't take someone else's word on them being done.

Thank you and God Bless
JDAS

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JDAS,

I don't have length numbers in hand, but while prepping 5.56 brass I ran into a lot that was short when gaged with a 223 case gage.
As I investigated the issue, I found the worst offenders were unfired LC brass. Really short brass will fire fine in an AR style rifle. I would insist it gage well with a 223 case gage before deciding to use it in a bolt action or single shot rifle.

Ron

mostly lever guns summary is good! As long as OAL is the same you're fine- you probably won't notice any case-length difference in everyday use.
Loren

If they're to short for the 5.56, they would be prime candidates for 300BO brass