I tried to figure out what was going on with my .310 Cadet. Put a dummy round in , close the lever and open the lever it pops out no worries. Put the same round in , close the lever , fire , open the lever and it wont eject. It does the same with live rounds and is very hard to eject the spent case. I have to push it out with a cleaning rod most times. I thought at first I was seating the bullet past the healed section and making it too big to fit in the chamber. But that dosnt seem to be the problem. I must be doing something wrong somewhere but I cannot figure it out.
Stab in a dark here, could it be maybe something worn in the trigger pack, maybe a spring or gummed up components. I am thinking, maybe, because it only happens after the trigger is pulled it could be the gun, not the cartridge?
From the way I read it. You have issues once the cartridge has been fired. If that is correct I would be first looking at the neck of the cartridge for any clues also if they have been fired before in another gun even though they have been sized. It can be an issue. If fired before in another gun the problems are normally around the base of the cartridge.
New cases how do they opperate?
Yes thats correct. Only an issue after they have been fired. New cases do the same thing and all my fired cases have been fired in the same gun. I have also tried a different projectile and the same thing happens.
Then it sounds like the case is expanding in the chamber when fired and creating a locking point at some point on the case. this may be just the base of the case expanding creating a lot of friction at the back of the chamber. ie the unsupported part of the case . It could be the very end of the neck being pushed out into a tool mark at the end of the chamber. Make sure your cases are trimmed sufficiently. Examine the fired cases very carefully for any evidence of where it may have been pushed out. It will look like a small crease possibly or a pimple a reverse dimple.
@Field_Marshal_Cinque aren’t you saying that this happens with a new case and dummy round? So does it mean that when you pull the trigger on a dummy round, you are seeing the same issue, implying that it has nothing to do with pressures and case expansion?
That’s what I thought he meant in the original post
Yeah thats right. Dummy round and fired round do the same thing. They both get stuck. The only way cases eject is when the trigger hasnt been pulled. Sorry for the confusion.
Strip and clean maybe? Inspect parts?
Is it possible that (1) the chamber is really dirty, or (2) its been rechambered and isn’t .310 cadet. I’m wondering if the firing pin hitting the primer/back of the dummy round is just enough force to push the case further forward into the chamber and thats why it’s only jamming when the trigger is pulled?
Re-barrel it in 357 that will fix it
The second option seems plausible, I remember there’s a thread on that here somewhere. Specifically about obscure rechambered Cadets. Will need to search for it…
I couldnt say for sure its not rechambered but its probably unlikely. The rifle used to belong to my grandpa and he said he brought it for $5 from a gunshop in Melbourne. I dont think he ever would have bothered with getting it rechambered but maybe it was done before he got hold of it. He also gave me some ammunition as well which was all . 310 cadet.
This is very cadet common, they are known for poor extraction. Check for obvious chamber roughness…failing that, keep your loads on the light side. AP70N is a good powder. AR2205 is great, but unburnt powder often results.
Well after probably too long I have figured it out. It turns out that the cases are too long and are jaming in the chamber after the trigger is pulled. Thanks for everyones help and sugestions. Now I need to get a trimmer.
Don’t forget a inside and outside deburring tool.
And then spin with 400 grit paper around the case mouth…
Thats what I would be trying first, they are so simple to strip …
310 cadets are sometimes a case of making/trimming cases to the individual chamber. I’m currently converting Statline 32-20 brass, because my rifle seems to hate Bertram…could be a simple chamber polish needed, though I believe.