Ring on Case Head

[hogpatrol]

Good grief! SMH. I'd post the name of the vendor. If there are other barrels out there like that, they should be recalled.

 

[hogpatrol]

Looking at that cone plus that chamfer id say dont send that barrel back- i retract my statement. That is the most rediculous chamber job ive ever seen and they shouldnt be given a chance to even attempt a fix. Chalk that one up as a loss and send it over to @Stan Taylor to get a proper chamber put in there. That is dangerous and doesnt fit any action period. Thats not a cone bolt chamber as i suspected thats attempted bomb making

That angles looks shallow too.

 

[swd]

That guy doesn't have enough common sense to own a gun let alone do gun work. Probably shouldn't own a car either. That's scary!

 

[rwj]

Interesting thread that led to reviewing the SAAMI chamber specification. The requirements for .308 Win is shown below. The last dimension for the chamber wall is .4714” diameter that is .200” offset from the bolt face. What are the shape and dimensional requirements of the chamber end face and the chamber ID surface over the .200” distance? Are they specified somewhere else in the SAAMI specifications? Are there generally accepted, though unspecified, riflesmith practices that govern them?

Also interesting to note that the .200” offset distance is common to many chambers, but the cartridge drawings do not specify the axial length of the solid section of the case head. Not questioning @DaveTooley reply, but if correct that the solid section extends .190”, every chambering theoretically has at least some length of unsupported case wall!

I’m anxious to read the input of the riflesmiths that belong to this forum...

 

[6MMsteve]

we missed something here>>> How Many barrels are like this that this guy chambered<<< hope it is 0 hope no one else has this issue

 

[6MMsteve]

Good grief! SMH. I'd post the name of the vendor. If there are other barrels out there like that, they should be recalled.[/QUOTEthat

WOW this could be bad

 

[DaveTooley]

Interesting thread that led to reviewing the SAAMI chamber specification. The requirements for .308 Win is shown below. The last dimension for the chamber wall is .4714” diameter that is .200” offset from the bolt face. What are the shape and dimensional requirements of the chamber end face and the chamber ID surface over the .200” distance? Are they specified somewhere else in the SAAMI specifications? Are there generally accepted, though unspecified, riflesmith practices that govern them?

Also interesting to note that the .200” offset distance is common to many chambers, but the cartridge drawings do not specify the axial length of the solid section of the case head. Not questioning @DaveTooley reply, but if correct that the solid section extends .190”, every chambering theoretically has at least some length of unsupported case wall!

I’m anxious to read the input of the riflesmiths that belong to this forum...

View attachment 1114197

The .200 dimension is just a reference location number for industry, nothing else. That's so everyone is speaking about the same numbers at a specific location. In the world of metrology a gage ball could be used to measure the diameter at or very near that location. If you sectioned a case the actual solid portion of the head is less than .190". The wall thickness at that dimension is so thick that even if it was unsupported @ .190" there would not be a catastrophic accident. Over several reloads the brass would probably flow and form a belt of sorts. Any of us old timers who started with Sako 220 Russian brass(balloon head) for the 6PPC remember the transition smiths had to make to tighten up the bolt nose clearance and stop using a chamfer on the chamber mouth. I still have several sets of brass that have a belt on them.
I chamber a lot to prints for various manufactures. Some of them have generous clearance between the bolt and the start of the chamber. All serious working rifles. Just my opinion but we, the custom smiths get carried away with making some things fit too close. I'd say most of us have .005"-.020" bolt nose clearance regardless of cartridge or action.

 

[Stan Taylor]

Well if that gentleman work for me at Douglas he probably would not work there long enough to get his first paycheck.