Ultralight Ultralight Rifles

[Trackselk]

Mine are all new cases. I was under the (incorrect) impression that your new cases wouldn't chamber, so nothing to do with my neck thickness idea. I doubt the neck has enough contact to affect extraction after firing as long as the round chambers.

The cases are sticking for some other reason, possibly what you're thinking with length. It could also be that they're just "stickier" than brass cases and need more force to extract than the Solo system provides, like it's inability to extract with larger diameter cases. A gasser has way more extraction force which is why gassers work with those larger cases as well.

I think that this "stickier case" might be the actual problem. Sometimes I have a case that's sized a little too long for a particular rifle and have to pull the Solo bolt all the way back and smack the bolt forward to get it to go into battery. Those cases are stuck in tightly enough that they're pretty much jammed in and are really difficult to extract without firing. Once fired though, they extract fine, almost like they rebound enough to fit more loosely. These NAS cases may just react and extract very differently than the brass cases we're used to using.

When I get time, maybe today, I'll run a couple through a Solo, a BCA, a gasser and my Tikka to see if there are differences in extraction.

Good thoughts. I think I vetted the length theory out with a ton of measurements, and it was fine. Then, as for the stickier idea, they are actually slicker, which is part of their appeal, especially for smooth running gas guns. After being fired, you can easily feel that they're too big for the chamber, and the case gauge helped me narrow it down to the shoulder, if I'm not mistaken. Here's a Pic of a new case sticking up .001" over max. So, add one thousandths of case stretch to the fired case and it's holding significant pressure against the bolt face. Phantom has seen a couple instances of this with bolt guns also, although we didn't get into the exact reasons for it.
I should have documented my measurements better in a devoted thread when I started trying to figure this out. But, multiple theories are better anyhow...

Edit: and if anyone isn't familiar with the case gauge tool, the other end is open, so the neck is free to extend through/not affecting the measurement in the pic. Or, in other words, this is a measurement of shoulder to the case head.
Looking at the other end, You can see if the neck is too long or short, which it isn't.

 

[Thegman]

Good thoughts. I think I vetted the length theory out with a ton of measurements, and it was fine. Then, as for the stickier idea, they are actually slicker, which is part of their appeal, especially for smooth running gas guns. After being fired, you can easily feel that they're too big for the chamber, and the case gauge helped me narrow it down to the shoulder, if I'm not mistaken. Here's a Pic of a new case sticking up .001" over max. So, add one thousandths of case stretch to the fired case and it's holding significant pressure against the bolt face. Phantom has seen a couple instances of this with bolt guns also, although we didn't get into the exact reasons for it.
I should have documented my measurements better in a devoted thread when I started trying to figure this out. But, multiple theories are better anyhow...

Edit: and if anyone isn't familiar with the case gauge tool, the other end is open, so the neck is free to extend through/not affecting the measurement in the pic. Or, in other words, this is a measurement of shoulder to the case head.
Looking at the other end, You can see if the neck is too long or short, which it isn't.
View attachment 855313

Shot three of the NAS cases loaded with 26 grains of LVR under a Hornady 75BTHP at 2.280" OAL
1ea through my UL-UL with a BCA Pencil barrel, Tikka T3 and BCA upper
All cases were 1.755" before firing
All extracted okay (the Solo was sticky but manageable, but a lot more difficult than it would be with a brass case and the same load)
All rechambered okay (Solo was a little tight)
Tikka case grew to 1.760", the other two to 1.767"
All cases very sooty, so not expanding much during firing

I'd say your guess about the cases wedging themselves in the chamber between the shoulder and base is probably correct. Need to measure the outer case dimension and compare to a typical brass case expansion, but suspect it will be fine there). This wasn't a terribly hot load. I imagine if it was, the cases would lengthen enough to lock up the Solo and at least start getting sticky in the other two.

 

[Welldone]

This may not be acceptable but I have my latest builds listed for sale/trade in gun classified.
Thanks