LC .223 brass good?

T

tangolima

New member
I'm pretty new to .223 Rem. Got my first AR and a bunch of once fired brass. The brass is mostly RWS and LC. I decided to use LC for the AR.

MV variation is noticeable with LC brass. Sigma is about 20fps, extreme spread is about 75fps. Group size is not too bad. Less than 2" R50 at 100yd. I think it is quite respectable for a military rifle, especially so for my cheaply built AR. But certainly I want to improve it a bit more.

Round-to-round labradar results clearly indicate correlation between flyers and extreme MV. Reducing sigma will pay off. I noticed different year stamps on the LC brass. Does the brass volume vary a lot from year to year? I probably will do some H2O measurements later, but it is a bit tedious and messy.

Thanks for your inputs.

-TL

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Lc is military brass generally. Sometimes it has a slightly smaller case capacity, but it is generally very good brass imho.

Machines and dies wear out. All brass has different lots, difference is lc generally stamps the year on theirs.

In relation to the ES issue, what powder, and was it weighed or thrown. Granted if the other ammo was ES 20 the lc should have been too.
 
Shooter's world AR plus powder, 25.5gr thrown. 3120fps mean, sigma 20fps, ES 75fps. 55gr fmjbt bullet.

I'm going to sort the brass by year stamps and try again.

-TL

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LC is good but is sometimes not manufactured at Lake City. On contract, Federal has made brass with the LC headstamp to mil-spec to supplement LC production, for example. Additionally, over time, tooling wears out and is replaced and variations occur due to that, as well.

LC capacity is not smaller than commercial. On average, it is actually slightly larger inside.

For consistent performance I would try several things to see which ones may help:

1) Sort the brass by year.

2) Sort it into batches by weight. I do this by laying out a large piece of paper with a ruler line across the bottom marked in tenths of a grain from the lowest to the highest weight I've seen. I then place each case above its weight's mark on the paper and the next one of the same weight goes above that first case, and so on until I have a column of same-weight cases there. This is a slow, but very revealing exercise. If you look at the columns as defining a graph of the weight distribution, you will typically get a number of peaks in the form of extra-tall columns for each different set of tooling that made the lot of cases.

This is an example drawn from data I collected on some Winchester bulk 308 brass I bought in 2005.

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3) Line the brass all up on a flat surface and sight down the line, looking for tilting cases, an indication the rims are bent. These tend to be less accurate and if the bend is on the shell holder's support surface, can be over-resized.

4) To really find out for sure that the above is mattering in your gun, invest in 100 pieces of good quality new brass just to see how the velocity SDs and group sizes compare on the first shot through it. Lapua or Norma or Nosler Premium (made by Norma) would be my first choices here for accurate results. A self-loading gun, because of the tendency to bend rims on extraction, will often shoot to its best potential with new cases that have never been fired.

If none of that helps, there is something else, a loading procedure detail or a gun or a gun handling inconsistency that is affecting velocity consistency.

A point of terminology: Your LabRadar is reporting SD (sometimes just "s"), or sample standard deviation, which is an estimate of sigma (population standard deviation). Unfortunately, we can't know exactly what sigma will turn out to be until we've fired and measured the whole population (all there will ever be of that load in that gun). Until then, we can only estimate based on what we have so far.
 
Thank you Unclenick.

I will sort by year and weight. New brass is possible when this batch is spent. The variation in MV may have something to do with the load being a bit light. The brass is a bit sooty. I'm still 5% below max. 3120fps seems to be a node for group. Currently the R50 group size is hovering 1.5"-1.8". I will stop when it goes below 1.5" consistently. It is a cheap (less than $500 build) in A3 configuration. It is shooting not bad as is, considering my lousy eyesight on peep sight alone accounts for 1" already.

I only use labradar for MV. Very consistently a group outliner comes with MV high or low. That makes me believe a low sigma will bring noticeable better group.

-TL

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is that a ball powder? google did not help much. looks like it should meter well. what barrel length those are some good velocities! are you using magnum primers? When I switched to magnum with CFE223, a ball powder, SD and ES cut about in half for me.

If it were me, for accuracy, i would tune seating depth. push it back 0.0030 increments, maybe 5 groups. I bet it will tighten up.
 
Also remember that these will have crimped primers so it may be harder to remove the primer. You will also have to remove the crimp before installing new primers.
 
Try some new good quality brass, like Unclenick suggested. That’ll give you an idea of the rifle’s accuracy potential. You need that data.
 
One of these days I'm gonna buy some premium brass and see how much difference it makes. I took a budget 1.5moa hunting rifle to a .75moa by tuning seating depth by .003 increments using mixed lot once fired winchester brass. Not sure how much more she has to give.
 
Good suggestions. Thanks.

The powder is something between small flakes and balls. Very well metered. Primer is tula magnum for military rifles. Primer pocket crimp is no problem. Seating depth is one of the things to try, after sorting brass.

I like the AR and the round. I am going to use it for practicing offhand target shooting / plinking. After that I have a mini-14 in the safe that I haven't had a chance to shoot yet.

-TL

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I like the AR and the round. I am going to use it for practicing offhand target shooting
Click to expand...

It's really a fun gun to shoot. I jumped in heads first in 2013 and started gouging out my own lowers using 80% lowers with a router and drill press. It's a really simple gun, very easy to build.

Then I woke up in California and all the fun went away. I still have a couple that I built but it's just not as fun as it used to be.
 
Military brass is often like their bullets. Each production lot of àmmo's cases comes from a few different sets of forming dies.
 
It must be pretty good. Bought two boxes of Winchester "white box" for my 7.62 at Walmart. Every round was a "LC" headstamp. Looked like I had reloaded it myself! Cases did not have that factory Winchester shine I am used to from BRAND NEW factory ammo. I had expected a Winchester headstamp.
 
Question: are you measuring ES starting with a cold barrel?
The values you got are what I've seen with new Federal xm193.
 
totaldla said:
Question: are you measuring ES starting with a cold barrel?
The values you got are what I've seen with new Federal xm193.
Click to expand...
I have 10 shots for each load. About 5 minutes between each load. It is not totally cold bore but close to.

So the variation is similar to the military ammunition?

-TL

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tangolima said:
I have 10 shots for each load. About 5 minutes between each load. It is not totally cold bore but close to.

So the variation is similar to the military ammunition?

-TL

Sent from my SM-N960U using Tapatalk
Click to expand...
I'm not sure that Federal XM193 qualifies as "military ammunition" because it has been a long time since the military has used M193. And the X means it is not Government contract ammo. I'm saying this because I don't know diddley-squat about M193 specifications.

But I own a chronograph and I've chrono'd a lot of ammo. I don't own anything with a nice barrel, so cold to warm barrel does show a big enough change in velocity to mess up a typical 10 shot string.
 
Thanks, total. If you observed similar variation in xm193, my load is at least not too out of whack. It is encouraging. MV is probably a weak function of barrel temperature. I don't see a consistent trend in MV as the barrel heats up.

I did the weight sorting. Different year stamps clearly show different distributions, although they overlap some. Among 4 different stamps, the weight spreads across 2.5gr around the mean of 37gr, which is 7%. Assuming same alloy composition, that translates into volume difference of more than 2gr H2O. It makes sense now.

I'm going to load with same year stamps. It will reduce the weight variation by half. Hopefully that will bring better groups. Will see.

It is indeed a fun rifle to shoot. Being such a cheap build, it shoots surprisingly well. I am certain it has no problem hitting man size target 90% of the time out 600yd. It is also quite reliable. I have fired about 150 rounds without cleaning. No stoppage other than a few misfeeds caused by the cheap metal magazine.

-TL

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Used LC brass back in the 70's and 80's when I first started out with TCU wildcats, never had any problems. In fact, many of those cases were still quite useable after many firings. With an AR, I see no reason not to use the LC. There have been a number of good suggestions on sorting methods given that should help. I'd start with lot and then weight.
Stay safe.
 
I think the brass has good quality. But its consistency may not be the best. It varies no less than 3% even with the same year stamp. It is good enough for government work I suppose.

-TL

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As many know I can get LC brass on the cheap in large lots 1k+ . This means I almost exclusively use LC brass for both 223/5.56 and 308 . This also means I have a ridiculous amount of different years . I do separate by year but don’t weigh my brass . I done a lot of H2o volume test with the 308 brass and it can vary quite a bit from year to year . I say can because most seem to be with in 1gr but I do have one lot of LC-14 that average 2gr off and it’s EX spread in that lot is almost as much . Not a good lot of brass .

That said , I've done some H2o test with the 5.56 brass but not enough to come to any conclusion. I do shoot the 5.56 brass A LOT and I don’t have any match or custom barrels . Moa or better with LC 5.56 brass is not a problem with multiple AR rifles for me . I won’t bother with the 100 pics I have of my targets you’ll just have to take my word on that .

OK maybe one

mJKNy7.jpg


Fine two of them ;)

rcyhew.jpg


Point is you should be able to do just fine with LC brass and the nicer your barrel and trigger the better it will do . Now if you are seeing large velocity ES/SD you might have vertical stringing issues at longer distances . I’ve never had great results with consistent velocities using an AR . Maybe thats the brass maybe that’s the platform but I can get really good numbers with the 308 brass through a bolt gun .
 
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