Modified case

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Has anyone made their own modified case from spent brass from their rifle? Is there someone on here that can do this for me? I watched YouTube but the guy made it on a Lethe which I don’t have access to. Thanks for any insight.
 
when you say modified case, do you mean a case threaded for the horady oal gauge
 
I did it with a drill and a tap, then I gave the tap to a friend who is a machinist and he made another one for me more accurate. I think you could buy a tap online and try it if you are good with that sort of thing.
 
What size case are you looking for? I've made a few. The smaller cases (.223, .222) were a pain in the ass because the diameter of the case is so close to the tap diameter and was just really hard to hold.
I've made them on a lathe, but the easiest way IMO is just using two pieces of wood, clamped them together, used a drill just smaller than the outside diameter of the case and drilling at the seam of the wood. This creates a wooden clamp that holds the brass just enough to not spin, but enough not to distort the brass. From there I drilled and tapped it out by hand. So smaller sizes I would recommend just buying the ones they sell. If it is a larger size or a more uncommon size, I say at least try it on your own. If you need the tap, feel free to come borrow mine (Auburn). Its a non standard tap size that I don't remember off the top of my head.
 
That’s a great idea. I did just find on YouTube a guy doing just that. I’m sure I can get the tap from fastenal. Thank you
 
Most cases are $6-8 cant see any value in sending in a fired case?

What you are trying to get is an accurate measurement of bolt face to where the ogive contacts the lands in your chamber. Unless the modified case has the exact same case head to shoulder dimension as a fully expanded case from your chamber, you're going to be a little off (but people have been known to say that about me :rolleyes:).

When using the Hornady tool, the contact points are where the ogive touches the lands and the case shoulder touches the chamber shoulder. Any difference between the modified case headspace measurement and the measurement from a fully expanded case from your chamber should be added or subtracted.
 
What you are trying to get is an accurate measurement of bolt face to where the ogive contacts the lands in your chamber. Unless the modified case has the exact same case head to shoulder dimension as a fully expanded case from your chamber, you're going to be a little off (but people have been known to say that about me :rolleyes:).

When using the Hornady tool, the contact points are where the ogive touches the lands and the case shoulder touches the chamber shoulder. Any difference between the modified case headspace measurement and the measurement from a fully expanded case from your chamber should be added or subtracted.
I see that but how much is it going matter.
What are Hornady cases shoulders set to?
max , min or somewhere inbetween.
i have the hornady 223 case. Looks like I will need to compare that to my fired cases from my match barrel.
 
SAAMI cartridge specification is 1.4596-1.4666. The factory modified case should fall anywhere within that range.

SAAMI chamber specification is 1.4636-1.4736. Your fully expanded case should fall somewhere within that range. That leaves a range of 0.014".

In my rifles, I want to know closer than that. I want to know the exact measurement from my boltface to where the ogive touches the lands. I didn't send in any fired cases. I used the factory modified case and added the difference between headspace measurements of the modified case and my case.
 
SAAMI cartridge specification is 1.4596-1.4666. The factory modified case should fall anywhere within that range.

SAAMI chamber specification is 1.4636-1.4736. Your fully expanded case should fall somewhere within that range. That leaves a range of 0.014".

In my rifles, I want to know closer than that. I want to know the exact measurement from my boltface to where the ogive touches the lands. I didn't send in any fired cases. I used the factory modified case and added the difference between headspace measurements of the modified case and my case.
So ideally you would want a modified case shot in your rifle to get as close to shoulder angle as possible then have and adjustable "split" case where you could adjust the case to darn near "zero" then you could use the guage to find COAL...
I wish there was a epoxy that only stuck to brass and you could "bed " a case to get your darn near exact Case/chamber specs. like chamber casting with cerrosafe chamber casting alloy but easier quicker.
 
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