20 practical brass question

P

pyscodog

Active member
Got my rifle today and my brass doesn't seem to be working. Its used 223 Lapua thats been fired a few times. I did anneal and rezize in a standard 223 die before necking down and resizing to 20P. It chambers hard and also hard to extract on a sized case. I just read where a fellow member was having similar problems with used brass and fixed it by running his brass through a small base die first. Is this what I need to do? A buddy made me a dummy round and his fits fine.We fired one of my loaded rounds at the smiths and it would not extract. One of his rounds loaded, fired and extracted just fine.Case length is fine, 2.760. Last step in necking down is a .225 bushing. Kinda lost right now, any ideas??
 
Small base die or try making sure your running your brass all the way up in your die. Shell holder touching your die.
Bottom line is your brass is not sized small enough.
 
+3 on the small base die. I ran 19 out of 20 on prairie dogs this afternoon with mine. Ranges from 100 yard head shots out to about 250. Wish I had got one running sooner.
 
I should note that mine is a Black Hole barrel, not sure if that makes a difference or not, but have heard that it may.
 
Here is the problem, Lapua brass is large, manufactured to CIP European spec. Your chamber reamer is probably not made for CIP brass(made in Europe), which would be SAAMI spec.

So, it is probably going to leade to headaches to use any European brass(CIP).

The issue of the base dia at the web will plague you, and as the brass gets work hardened, things may get worse.

This gets complicated, bottom line, use brass that matches your chamber. If your gunsmith uses a reamer set up for CIP brass, you can use Lapua and Norma brass, otherwise, use SAAMI brass or brass made in the USA.

This especially applies to Lapua cases in custom match chambers. With factory chambers that are large, often you have no issues with Lapua or Norma brass.
 
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Blackhawk43 is correct. Lapua brass is .002 larger in the neck than most American brass. I found this out on my 223 and 223 AI that has .250 necks where the Lapua measured .252 VS .248 with American brass.

You neck down the 223 brass, it gets thicker.
 
I used once fired LC for my source and had to use the small base dies; I don't have any idea how new brass would do, but would like to know.
 
Brass that has been fired in an AR has huge expansion on the web, brass has a memory, thus you size it down, it springs back out.

New brass has no memory of a chamber, yet.

Using once fired brass, fired in a AR chamber can lead to problems due to web expansion. Start off with new brass when ever you can, especially if you have little patience with stiff extraction and having to resize often.
 
Scraped the idea of using Lapua brass. It was hit and miss as to whether or not it would chamber. Had to buy a Small Base die and first ran the Winchester brass through it. Then through the .233 bushing, then the .225 bushing. Everything seems fine now. Still plan on buying some new brass to form another 100 pieces. Thanks for the help guys!!!Now to figure out what to load for it.
 
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I never had to run any of the 20p brass I made through a SB die. I used BHW barrels.
I used a mixture of brass brands but never lapua stuff.
 
I read on the Saubier forums that loads for 223 using 68-70 grain bullets will work for the 20Practical using 39-40 grain bullets. Of course starting under max and working up. Does this sound about right? Looks to be in the same grain weight range as what I'm trying now.
 
I only used 20 tac data and started 3-4g gr less when I was working up loads.
I also used .204 data and extrapolated loads from them starting 4-5g less.
 
Originally Posted By: carvercallsI had the same issue, ran them through a small base die and the problem was cured.

Ditto. My barrel is a BHW 20 Prac barrel BTW. I use once fired LC brass exclusively for it.
 
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