My first custom chamber: 300 Ultra X! (Creedmoor was taken)

Serious answer, I've been wanting a 30-28 nosler. I might cut it down .260" to meet the chamber specs of the 28 nosler and see where we end up. Maybe even cut it down to 30 nosler specs.
 
I considered threading the current barrel and drill and tapping another piece. Had a friend do this with a barrel. I'll have to ask him how it worked out. I know he's still alive cause we still fish together ;)
A barrel extension for a bolt gun...I'm pretty sure sched 80 pvc would be just fine, that stuff is just heavenly to cut internal threads on, good surface finish, and if you end up a little sloppy you can melt-to-fit cuz you dont have to worry about screwing up the heat treatment. I dont know why we aren't seeing these popping up everywhere...lol

Before all you literal minded OSHA lovers out there freak out, this is totally just a joke.

And to anybody ignorant enough out there not to know better you will die if you try this. Not like "I just died in your arms tonight" die, more like your entire head will become a spray of pink mist as it detaches from your head kinda die.
 
[I will get a good print made up. Imagine a 300wsm the length of a rum. It adds a 35deg shoulder and a flat from the base to the .74" mark in the chamber. The base and shoulder diameters are slightly larger. It allows for an extra 4% capacity over the standard rum with basic computations, but I haven't finalized the using Gr of water.
View attachment 165481

MNbogboy:
Something like this? Water capacity automatically calculated. Curious how close this is to your thoughts on design. The COAL was auto generated and not probably close to what you have.
 

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Ok here is another drawing from 300RUM as parent case that is similar but interesting has less capacity according to calculations by software. Just a curiosity to see what it looks like.
 

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[I will get a good print made up. Imagine a 300wsm the length of a rum. It adds a 35deg shoulder and a flat from the base to the .74" mark in the chamber. The base and shoulder diameters are slightly larger. It allows for an extra 4% capacity over the standard rum with basic computations, but I haven't finalized the using Gr of water.
View attachment 165481

MNbogboy:
Something like this? Water capacity automatically calculated. Curious how close this is to your thoughts on design. The COAL was auto generated and not probably close to what you have.
If you followed this post your suggestion is exactly what Mram10us has done and tried.
 
I probably wasn't clear enough in my postings; I was just showing actually drawings of what Mram10us said he was going to get done. A print of his design so I just thought it would be nice to give examples of what it may look like for him. Not suggesting my own design at all. Not sure why I referenced MNbogboy though.
 
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Thanks MB. I can't get your file to download just now. Thanks for the effort. I'll check it out. I tore it all apart today and made the next project. Definitely learned a lot about flats in a chamber :)
 
No problem, I have the old RCBS software that lets you draw up a design mostly off a parent case so it is nice to actually see somewhat it might look like which may give additional thoughts to design. Anytime if you need to see something especially capacity.
 
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