Norma 6Dasher Brass
- Thread starter Shiraz
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rcw3
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Tom
Not doubting or challenging you on how you do your measuring. The diameter of the brass there (mine anyway) does change rather quickly as I move ever so slightly forward or back in that .200" spot and really my mic jaws are like yours (i.e. not exactly ideal for measuring that spot) so now that begets something else:
1. In truth, why is .200" forward of the base even a relevant measuring spot, since the web is short of that spot and the second you fire the brass it will likely never be the same diameter there ever again unless you FL re-size and your resize die just happens to put it exactly back at that diameter again?
2. Do not know about others, but with Lapua brass in both the Dasher and BRX, I noticed the web and base case diameter grows as cases were fired (e.g. if I started out with new brass at say .469", by 2 - 3 firings it might be .4695" - .470" and after like 5 - 8 firings it might be .4705" - .471"). A customer of ours gave me some brass he had about 12 firings on it and it's up around .472" - .4725". Now my loads are around 31 gr of H4895 with naked 105 - 108 gr bullets (low 2900's velocity) so I am not ripping things like I see with some of the loads that get posted here. Are any others seeing this type of growth?
Robert
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rcw3
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Tom
I assume when you say .470" - - you're speaking of .470" at a spot forward of the web (perhaps right around the .200" or so forward mark). Never found I could control the web diameter growth with the chamber diameter or a re-size die, but if web dia. got too big then things could get tight in the back end so that cases became sticky and a FL re-size die got to the point of not doing it well any longer (i.e. big web diameter would cause brass just forward of web to spring back a good bit regardless of the re-size die). The scenario is not one that for me was just limited to the BRX or Dasher, but I also saw it and dealt with it shooting long range with the 6.5x284 and the 284 Win. Not sure if others have had this. For the 6.5x284 and the 284 Win I had a special small base die made up that I used every so often to stretch a little more life out of some of the brass.
Robert
rcw3
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Weird perspective of your photo - - it looks like the jaw on the right in your picture is right on the web but on the left it's forward a bit, but I am sure that's not the situation.
IMO - mic jaws like that (we all have the same type) are not exactly ideal to try to place at exactly .200" from the base and measure that spot anyway - - if a measurement there is actually even relevant with new brass.
dmoran
Donovan Moran
Pretty blurry picture.... it was the best of 3.... lol
There is small variation from case to case. Min to max, they will be in the 0.467 to 0.4675 neighborhood.
Which is 0.001 to 0.0015" smaller then any Lapua's that I have measured.
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I checked to see if these cases would go into my 21st Century primer tool and 4 out of 41 would not go in.
I think I will put them in my Wilson case holder, chuck it in my lathe with the head out and shave the the grove side down. It shouldn't be hard to shape a tool if I don't have one that will work.
I think I will put them in my Wilson case holder, chuck it in my lathe with the head out and shave the the grove side down. It shouldn't be hard to shape a tool if I don't have one that will work.
Thanks Donavon Alex Tom it looks you guys would make pretty good machinist.
Stan
rcw3
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Just tried out some of the new Norma brass - - fired 5 of them 2x - -
Chamber is a chamber from a number of years back on a 30" Krieger 8" twist barrel and a Barnard P Single Shot Action. Chamber was originally made up for Lapua 6BR brass made into 6 Dasher brass (neck is .272", max case length is 1.558" with a .124" free bore and 1 1/2 degree throat angle, .4708" @ .200" forward of bolt face, etc.).
Load was 32 gr of N140, CCI BR-4 primer, Berger 108 BT bullet, in the lands .012" (runs just around 2900 fps in this barrel).
Trimmed the Norma brass to 1.550" OAL initially (ouch - - hate trimming off .049" of brass off the neck but needed to for it to fit in the chamber)
First firing - - diameter right forward of web immediately went out to around .4715" and web was around .4705".
Then resized brass with FL sizing die
Web diameter at .4705" and area just forward of it the same.
Re-primed and noticed primer pockets not quite as tight now.
Second firing - - same load as before
Then resized brass with FL sizing die
Web diameter still at .4705" and area just forward of it the same.
Re-primed and noticed 3 of the 5 primer pockets are pretty loose now (not sure whether the cases will be usable after another round of firing).
One thing is clear for me, the above load, in my set up, while it was ok for the Lapua brass, is too hot for this brass, and the primer pockets will not hold up to multiple firings with that load.
Nice brass, just not sure how hard and durable the base is - - we'll see!
Chamber is a chamber from a number of years back on a 30" Krieger 8" twist barrel and a Barnard P Single Shot Action. Chamber was originally made up for Lapua 6BR brass made into 6 Dasher brass (neck is .272", max case length is 1.558" with a .124" free bore and 1 1/2 degree throat angle, .4708" @ .200" forward of bolt face, etc.).
Load was 32 gr of N140, CCI BR-4 primer, Berger 108 BT bullet, in the lands .012" (runs just around 2900 fps in this barrel).
Trimmed the Norma brass to 1.550" OAL initially (ouch - - hate trimming off .049" of brass off the neck but needed to for it to fit in the chamber)
First firing - - diameter right forward of web immediately went out to around .4715" and web was around .4705".
Then resized brass with FL sizing die
Web diameter at .4705" and area just forward of it the same.
Re-primed and noticed primer pockets not quite as tight now.
Second firing - - same load as before
Then resized brass with FL sizing die
Web diameter still at .4705" and area just forward of it the same.
Re-primed and noticed 3 of the 5 primer pockets are pretty loose now (not sure whether the cases will be usable after another round of firing).
One thing is clear for me, the above load, in my set up, while it was ok for the Lapua brass, is too hot for this brass, and the primer pockets will not hold up to multiple firings with that load.
Nice brass, just not sure how hard and durable the base is - - we'll see!
I would like to know the diameter of the rim after a couple firings with these relatively warm loads.
Thanks
Thanks
Okay could someone that has shot this brass give me rim diameter after firing an before measured at the widest point.
Thanks I would appreciate it.
Wow, that's the exact information I wanted to know! My reamer is based on the print on your website except mine is a .269 neck and I use a sizing die I purchased from you. I assume there is a noticeable bulge at the base after firing as there is expansion from the case being smaller, as is primer pocket expansion as well. I purchased 300 cases of this stuff and so now I know it will be useless to fire it in my current chamber. I really REALLY didn't want to have to rechamber just to use this brass more than 3 times!
Thanks for the info!
Does the Sinclair priming tool work as is with the Norma Dasher brass?
SHall
Silver $$ Contributor
The Sinclair priming tool (hand held) model works! I am trying out the brass also and have been looking today for the easiest way to prime it. Or should I say anyway to prime it. My Lee Auto Prime shell holder will not work that I always use. I have a RCBS Rock Chucker that would work if I still had the small primer plunger for it. Must have lost it sometime since my parents bought it for me in 1979. Anyway, I had bought a Sinclair Priming tool to load 300WSM's. Lucklie I had bought a Small Rifle Primer plunger and BR shell holder in its box. Tried it today and works with room to spare! Wa-hoo, I'm in business! Samuel Hall
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