jerkface11
Member
Work up the load separately for the different brass.
it is not ...smaller volume LC brass.
Guys,
Again, understanding that I am somewhat new to this I have a question about fireformed brass..I understand what it iss and that it contributes to brass longevity but what's the process..
If I go to the range today and shoot 300 rounds of FL sized brass, would I then come back to the bench and just neck size those, reload, and shoot again?
Hi Guys,
Ok..I was loading up some .223 tonight with 75gr HPBT's with Varget. My cases are a mix of CBC,(5.56) LC 13,(5.56) and RP(.223).. Started at 22.5 and worked up to 23.5..
I noticed that the case on the military rounds are more filled than the .223 and I am sure this is due to the brass being thicker in the 5.56 cases. On those, its basically a compressed charge even though it's well below "max" according to Hodgen and Lee..
Anyone give me some info on this type of situation? Safe? Not safe?
For the case volume to make sense, or to be of use, it should be fire formed as this is the accurate measure of the case when under operation and reflects the chamber dimensions.
Agreed. You need to work up a new load for different types of brass. Using Min loads is probably ok for plinking loads with mixed brass, but if you want to approach max loads, you need to work up loads independently for every different set of components. You'll never have much precision mixing brass.Work up the load separately for the different brass.
CorrectBut RN should be working with full length sized cases in an AR type rifle ... not fire formed cases ... he will have to deal with the volume of that sized brass as far as compressing/not compressing powder when reloading... while it is true that the shape of the chamber would have an effect upon firing...
I do want to add that I have no LC brass that is newer than 2011 ... so there may be some heavy LC brass out there ...
I agree as to 5 places to the right of the decimal as to the VMD and thus used them. The point of my post was take for example full length sized 223 brass verse for example a once fired case that has been fire formed to the size of a chamber. How much will the case volume actually change? Take a look at the data JimKirk posted. There were 17 different cases and that discounts that case volume changes lot to lot and even within a lot by a single manufacturer. That is a given. So using JimKirk's data chart I added up all 17 examples and got an average.RN, my favorite .223 Rem load is 24.0gr of Varget with a 77gr SMK bullet (loaded to magazine length) in a variety of .223 Rem cases including Remington, Winchester and Federal. This is a compressed load but it's a known good performer in numerous AR rifles.
Reloadron, I have to wonder about the 5 decimal places in the VMD chart in the link below.
http://www.leeprecision.com/cgi-data/instruct/VMD'S.pdf
Case #1 in the chart held 30.6 grains of water and case #17 held 28.0 grains of water. So the difference between case #1 and Case #17 was 2.6 grains of water. That is about 0.168CC of volume in the cases between the Max and Min case volume. That is a given so when loading identical powder charges in both cases how much difference will that make in chamber pressure? More important is will that difference even matter? Will it be significant in light of the cartridges intended use? Will my rifle explode?
Not seeing any mail yet.Ron, you have mail.