3x fired brass not chambering - 300PRC

So according to the OP his sizing die is able to size Hornady brass but not ADG.

His measurements of both cases show ADG to be larger in diameter than Hornady after sizing.

It’s obvious the ADG brass is harder and springs back more after exiting the die.

The answer is a custom small base die or a bigger chamber. It’s easier to open up/polish the chamber.

But another answer is to just use Hornady brass. Save the ADG brass for your next barrel which will have a bigger chamber now that you know the problem.
 
Necro thread alert! I've got .532 at .200 up from the base on my sized brass. The brass has 3 firings. The barrel is a Mcgowen remage. I'm going to pull the barrel and open up the chamber. How much does it take? .001 or .002 or more?
 
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Al Warner makes sublime dies. The only problem is that you end up wanting them for every cartridge. Hell, I'd probably buy one in 9mm if he agreed to build it. lol.
 
3x fired. Sized.
20220318_201714.jpg
 
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And the 3 times is sized? I'm assuming yes but you didn't specify like the 2x.

How do you set headspace? How does your fired case headspace compare to saami? Being a barrel nut setup do you consider how you set the headspace has an effect on fired case size?
 
I set the head space with go no go gauges. I took a 1x fired case and sized it bumping the shoulder back until the bolt would drop closed by itself. The 3x is sized. I edited that post. I also took the sized 3x case and sharpied the base and web. There is a nice clean ring around the case at the .200 mark.
 
I set the head space with go no go gauges. I took a 1x fired case and sized it bumping the shoulder back until the bolt would drop closed by itself. The 3x is sized. I edited that post. I also took the sized 3x case and sharpied the base and web. There is a nice clean ring around the case at the .200 mark.
Do you set with the go or no-go?

If you set the headspace using the no-go guage will the brass chamber? No-go is still acceptable just on the larger side.

What is your actual headspace measurement and how are you measuring?

What I'm getting at is that you can set headspace smaller than your die can size. You might be on that cusp.
 
Do you set with the go or no-go?

If you set the headspace using the no-go guage will the brass chamber? No-go is still acceptable just on the larger side.

What is your actual headspace measurement and how are you measuring?

What I'm getting at is that you can set headspace smaller than your die can size. You might be on that cusp.

It’s likely not the headspace. As his previously fired and sized brass was working. So his die was able to shorten the headspace previously.
 
But easy to check.

Take measurements of the case body and then keep screwing die down and see if you can get the body sized any more.

If so, set the headspace .002 or so longer than that sized case. If it chambers correctly after, problem solved. Unless it ends up being too short for virgin brass.

If not, you can either:

- shave some off bottom of die (may or may not work)
- enlarge the chamber (also might not be the correct move if it’s the die that’s issue)
- get a die that sizes smaller or have custom die made
 
Necro thread alert! I've got .532 at .200 up from the base on my sized brass. The brass has 3 firings. The barrel is a Mcgowen remage. I'm going to pull the barrel and open up the chamber. How much does it take? .001 or .002 or more?

Your problem is that your sizing die is not sufficiently small enough in diameter to squeeze down your brass to fit in the chamber. You can't fix this by pulling the barrel and "opening up the chamber" by backing the barrel out a bit to increase headspace. That's going to make the chamber longer but it's still going to be too small in diameter.

The only way to fix is to get a different sizing die that has a smaller internal diameter, or by recutting the chamber with a reamer that has a larger diameter.
 
It’s likely not the headspace. As his previously fired and sized brass was working. So his die was able to shorten the headspace previously.
Just spitballing here. if he already has the die bottomed out and it's only bumping .002 I'm inclined to think his fired brass is on the small side and he could do with more headspace which would in turn alleviate pressure on the sides. Since cases are tapered like a cone inside a cone.

Typically, If you bottom a die out how far would it push the shoulder back?
 
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Your problem is that your sizing die is not sufficiently small enough in diameter to squeeze down your brass to fit in the chamber. You can't fix this by pulling the barrel and "opening up the chamber" by backing the barrel out a bit to increase headspace. That's going to make the chamber longer but it's still going to be too small in diameter.

The only way to fix is to get a different sizing die that has a smaller internal diameter, or by recutting the chamber with a reamer that has a larger diameter.
This is probably the case.

Are you annealing this 300PRC brass?
Probably not the issue but it is a variable.


I’m kinda thinking I’m going to get this with my 7 saum.
My smith custom specs his reamers and it works fabulously with my Redding body die(he knows his shit) with both barrels easily taking the same brass and excellent brass life wit no hassles.

My reamer (PTG) has a tighter body and I’m a bit Leary it’s going to get me clickers and issues like the 300PRC
I’ll probably borrow some gauge pins and get the body specs from my old barrels and spec a reamer for JGS.
 
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Your problem is that your sizing die is not sufficiently small enough in diameter to squeeze down your brass to fit in the chamber. You can't fix this by pulling the barrel and "opening up the chamber" by backing the barrel out a bit to increase headspace. That's going to make the chamber longer but it's still going to be too small in diameter.

The only way to fix is to get a different sizing die that has a smaller internal diameter, or by recutting the chamber with a reamer that has a larger diameter.
Recutting the chamber is what I meant by opening up the chamber. Not adjusting headspace.
 
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No, it has not been annealed.
Well with magnums your definitely getting to the point where brass(especially ADG) will be hard enough to start requiring die adjustments to maintain headspace and resistance issues.

I quickly learned that with my 338 edge, my 260 and 7 saum are totally happy to be annealing after 3-4 loadings

My 338 absolutely needs be annealed at most after 2 firings.
 
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But easy to check.

Take measurements of the case body and then keep screwing die down and see if you can get the body sized any more.

If so, set the headspace .002 or so longer than that sized case. If it chambers correctly after, problem solved. Unless it ends up being too short for virgin brass.

If not, you can either:

- shave some off bottom of die (may or may not work)
- enlarge the chamber (also might not be the correct move if it’s the die that’s issue)
- get a die that sizes smaller or have custom die made
It's even easier than that. Simply hand tighten the barrel down on the no-go guage. Then check if sized brass fits. If it does then you know you can size it to fit.
 
Do you know anyone else who reloads 300prc local to you ? Go for a short drive with a few pieces of brass and your rifle/barrel, size them.

I have see out of spec dies more than a few times, however i do understand you said its firef a few times, and was working previously.

Cheap just to try a different brand body die..
 
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Update on 3x fired and sized brass. It will chamber in a X Calibre barrel that was headspaced with the same go no go gauges that were used for the McGowen barrel.
 
I'm working through a similar issue, my troubles were related to extraction however...... What kind of die are you using? I ran into issues with ADG brass with multiple firings and a hornady die sticking in the chamber making the bolt difficult to pull to the rear.

I picked up a redding type s bushing full length die and it's noticeably tighter in the .2 case web area. Initial testing with a couple rounds I think I might have my issue solved. My redding die is getting ADG brass down to .528" at the .2 measurement. For reference my hornady die was only able to do .5295".

Edit: My fired cases are .531"
 
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