- Thread starter karagias
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A quick glance at a half dozen .473 case headed cartridges confirms my assumption. They all go from a .409 groove diameter .109” from the case head to a .471 body diameter at 36°. I only have 3 different cartridges on hand, in 2 different brass manufacturers for each, and they all check out the same. I guess my sample sizes aren’t that large. I’d be interested in knowing which brass companies are deviating from spec, but I think it’s safe to say, if you’re using Lapua, Peterson, or Alpha brass, and you drop a sized or new case in your chamber, and the coned breech clears the body/extractor groove junction, you’re probably not going to have issues.
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Those dimensions are controlled according to SAAMI spec and it's available freely on their website. I think the point was more that those dimensions are not a robust indicator of whether the barrel is in spec or not. So sure those dimensions can be correct but that doesn't translate to the barrel being to spec.
If those dimensions are correct, and the cone doesn’t pass the extractor groove, then mathematically the cone is out of spec. So while you’re technically correct, that the cone passing the groove doesn’t mean it’s in spec, it’s clear that there is more tolerance on the side of being deeper rather than shallower, until you run into unsupported cases. That’s a decent amount deeper.
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And that would work on .223 sized case head, but on something in the .473” family, the extract groove taper extends to .152”. That could be the cause of some confusion, especially visually. I’ll draw a 308 case head into my model tomorrow.
So, the intersection of the coned breech and the chamber is proud of a saami spec .473 case head extractor groove by .005”.
As long as that means the extractor isn’t touching the cone, which I’m sure it does, all good. Using a case as a gauge in my previously prescribed manner is not correct, for a .473” case head, but will work for a .223 based cartridge.
As long as that means the extractor isn’t touching the cone, which I’m sure it does, all good. Using a case as a gauge in my previously prescribed manner is not correct, for a .473” case head, but will work for a .223 based cartridge.
Just got shipping notification for my 7 PRC barrel from Carbon Six. Now just need my action yet and I’m ready for assembly.
Got shipping for 0373xx this afternoon. 0.473 bolt face, red hourglass,
20moa long action.
Just kidding. It’s short action.
20moa long action.
Just kidding. It’s short action.
I'm OCD when it comes to unsupported case but apparently 223s can have a small amount of unsupported case body and still be safe. I like the fact that my Defiance Deviants and ARC Nuc have a short enough bolt nose(.125" and .115") that it allows the chamber to be cut with a fully supported case body.
Going to order a chassis for my CDG build. Any reason not put the CDG in a MPA Ultra Lite?
Got my shipping notification for my 2nd action, should be here Friday… going to get my butt in gear and decide what caliber to do it in and order my barrels.
There was a post way earlier in this thread, perhaps by Ted, that showed the relationships of bolt to case presentation in a flat versus coned breech face. It clearly illustrated that a coned breech face actually supports marginally more of the case than the flat face. Remember that your bolt nose and extractor need to enclose the case head in order to extract the case.
Which bolt style do you think gets closer? Hint, it’s the coned bolt face.
I was specifically referencing the picture. Maybe it's possible to have a completely supported 223 case with the CDG but it's not in that picture. Idc, which one "gets closer" as long as it completely supports the case which my Deviants and Nuc both do.
Do you have a picture of the case in the barrel? Post it.
That 223 is fully supported. If you cross sectioned a case you’d be able to tell.
No it's not.... I'm fully aware that brass is thicker with most cases at that point but not all manufacturers have the same case head depth(or thickness depending on how you look at it). Federal 223 brass had issues with thin/short case heads years ago that was apparently well know. Like I said it's a general consensus that a small amount (no agreed upon measurement) of unsupported case body is safe with 223. On the other hand plenty of BRs and creedmoors have had case head seperations with that amount of unsupported case body.
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Okay, humor me. I checked the posts I quoted and all the posts for the past two pages. At what point did you post a picture of your deviant and/or nucleus with a case on the barrel showing they were fully supported? For that matter, where did you post a picture of anything that I quoted that showed a case in a chamber?
That’s the question to go with your statement.
Thanks.
Is that so? And your proof to that statement is what?
I’m truly interested in education and knowledge, so statements like that need some kind of support to be taken at face value.
That is a 100% fully supported case.
You asked for a picture of the case in the barrel which was in the post I quoted..... You never asked for a picture of a case in my barrel which are currently my match rifles and are not coming apart to argue with some rando on the internet. I have zero reasons to lie about my rifle.Okay, humor me. I checked the posts I quoted and all the posts for the past two pages. At what point did you post a picture of your deviant and/or nucleus with a case on the barrel showing they were fully supported? For that matter, where did you post a picture of anything that I quoted that showed a case in a chamber?
That’s the question to go with your statement.
Thanks.
Just a picture of a case in the barrel is fine.
Wow, you found a picture of one case in which you have no idea of the manufacturer. Are you nieve enough to think that all 223 brass manufacturers have the exact same tolerances in the thickness of all the areas of the brass.
For what? You would see the back of the case in a chamber..... Listen guys if that picture gives you warm fuzzies than by all means run it. I'm sure it will work fine and I have zero desire to argue what constitutes a fully supported case. Have fun gents.
So we should expect absolutely no supporting evidence to your statement? Just, “trust me bro. I’m a rando on the internet.”? Gotcha.
Actually, you have provided me with zero pictures of cases in barrels and I surely didn’t quote one of your posts with a picture. I asked you to humor me and post. At this point you are just some rando on the internet arguing with zero evidence or proof of anything. No pictures, no proof, no evidence, just an argument and nothing else.
Your comments and arguments are just blather unless/until you show a reason that I should believe you.
Personally it doesn’t matter as I know whereof I speak. You? Who knows?
Hahaha! Okay, I hope you had fun getting in deeper than you expected. Have a good night.
Seems unfair to those of us still waiting for our first…
And…?
This has exactly what to do with my question to you for evidence that flat faced breeches protect more of the case?
That is what you are contesting and have yet to show any evidence to support. That’s what I asked for. We all know that there are pictures of cases in Cone breeched barrels. There’s a few posted here already. Where’s a picture of your defiance and/or nucleus with a case in the chamber? That would help to support your argument/contention.
That’s what this discussion has always been about since you entered the conversation. I’m willing to be educated. Show me.
This has exactly what to do with my question to you for evidence that flat faced breeches protect more of the case?
That is what you are contesting and have yet to show any evidence to support. That’s what I asked for. We all know that there are pictures of cases in Cone breeched barrels. There’s a few posted here already. Where’s a picture of your defiance and/or nucleus with a case in the chamber? That would help to support your argument/contention.
That’s what this discussion has always been about since you entered the conversation. I’m willing to be educated. Show me.
That is true... One of us does and it's not me. I literally said the picture is in the post that you quoted.... The first post that you quoted of me is the link to the picture.
While it's obvious that you are high functioning retard I guess I will entertain this ridiculous line of questions.
1: I never said "flat faced breeches protect more of the case than cone breeches". I said I like that my Deviant and Nuc short bolt nose allows the case body to be fully supported. I'm sure there plenty of cone face breech chambers that fully support the case body just not the one in that picture. Doesn't mean the one pictured is unsafe I just prefer more.
2: Evidence for what? That the case sits deeper in the chamber of my barrels? Why would it matter if accoording to you and tokay444 the case in that picture by definition is fully supported. I already told you I'm not taking my barrel off to prove a point to some tard on a gun forum. Also, taking a picture from the action wouldn't show the angle needed anyway.
3: What am I supposed to be educating you about? The fact that I like as much of the case body to be in the chamber as possible. It's my preference... Consider yourself educated.
I don’t appreciate you making fun of retards. My President happens to be retarded and he’s doing just fine.
Because I had a pile of barrels on the shelf…
AX 6.5cm
Zeus QC 6.5cm
Badger M2013 .308 x2
Deadline 2 300NM
Filthy old R700 factory
Archimedes 6.5cm
Idgaf about the argument, but here’s some data anyway.
AX 6.5cm
Zeus QC 6.5cm
Badger M2013 .308 x2
Deadline 2 300NM
Filthy old R700 factory
Archimedes 6.5cm
Idgaf about the argument, but here’s some data anyway.
I'm not sure why the coned breech is such an issue.
I don't think it's super critical weather or not the case head is fully supported.
Some of the Mausers were quite shallow & they seemed to be ok.
I don't think it's super critical weather or not the case head is fully supported.
Some of the Mausers were quite shallow & they seemed to be ok.
Sure am.
All fully supported also. Nothing in .223?
We don't want the case head fully supported. We do want the case body fully supported, and the coned breech does just that.
