Brass volume new vs once fired

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Nov 16, 2017
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One of my primary arguments to the brass capacity arguments is Ackley cases. I've built several and they always shoot well with both parent and formed cases.
Idk man just switching brass manufacturers can make a difference.
My 300 was 1 grn less with Nozler vs WW
And I planning on having to drop a grn when I cycle in the ADG as well.

Adg is known to spike pressure at the same powder charge.
 

Wrench

WKR
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Idk man just switching brass manufacturers can make a difference.
My 300 was 1 grn less with Nozler vs WW
And I planning on having to drop a grn when I cycle in the ADG as well.

Adg is known to spike pressure at the same powder charge.
Different components will absolutely make case volume differences which change pressure drastically.

Same case with different dimensions is very difficult to measure the performance gains. Every f class winner bumps about. 002". Why not neck size?....because mashing a case thst was tight will lose a match and a sized case doesn't. Keep in mind these guys tend to shoot the tight side of the chamber spec to minimize brass movement.....but some are also getting 20 plus firings on brass.
 
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One of my primary arguments to the brass capacity arguments is Ackley cases. I've built several and they always shoot well with both parent and formed cases.
Agree. My 35 AI shoots well with factory brass or fire formed brass.
 
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Jul 24, 2021
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Reviving this thread because I just went through a similar situation when I rebarreled my 7mm mag.

I was shooting a 145 LRX in virgin ADG brass with 66.4G H1000 and was getting about 3120 fps and about 1/3 moa groups off the bench. I was very happy with this and decided I’d have Leupold make my CDS dial for my vx5 based on this load.

Now with the once fired brass, shoulder bumper about .002”, the same 66.4G charge netted me 3060 but also had an extremely low SD. Something like 5 or so on my limited testing. Only problem was the cds dial I ordered with a fps of 3120.

I ended up using 67.5G H1000 to get back to 3120. It’s over Barnes max load, but is super accurate and I get no pressure signs other than primers starting to flatten.

Simply sharing my experience to help others having trouble with their loads. Please don’t use my load data.
 
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Sharing loads that are admitted to show pressure signs and over book is not prudent. Sharing an experience about going over book and primers starting to flatten is one thing but to publish the numbers has no purpose.

Starting to flatten means they are not what they should be, and a different sign from before. Going over pressure to match a CDS dial isn't a desirable load.
 
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Sep 30, 2019
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I have verified the new brass load. Although not as good as the first group it still shot better than anything I have shot with fired brass, including those where I changed powder weight up and down .5gr and .8gr

Hi OP

Are you using a neck tension mandrel on the 1x-fired brass before seating bullets?

If your neck tension isn't uniform you could be all over the place in terms of how tight the bullets are being held by the brass necks.

Reason I bring this up has to do with having pulled lots of bullets that were loaded by people I don't know. [I have two calibers that are difficult to find brass for so I will buy loaded ammo, pull the bullets, salvage the brass.] When pulling bullets with a collet, I more often notice the neck tension to be VERY inconsistent from the same load batches. Some bullets come out too easy, some normal, some require a ridiculous amount of leverage and muscle to remove.

My guess is most reloaders size using the expander ball method (I don't). If you're not using a mandrel, and your expander/die isn't reliable, causes me to think that your accuracy trouble might have to do with inconsistent neck tension. Just a thought. :unsure:
 

Wrench

WKR
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I could never put faith in a drop dial in this component crisis. Stocking up on same lots is nearly impossible and lot to lot variations is a serious issue with trying to match a turret vs the opposite.
 
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