? for folks smarter than me...well ok, ? for everybody

[Ridge Runner]

should you always be able to insert a bullet into a fired case by hand?
what would be a minimal neck thickness?
I turned the 6.5 casenecks to .012 and its alot better but I still can't force a bullet into the case by hand before resizing, in my resizing procedure, the hardest part is getting the expander plug through the neck on the UPSTROKE!
JS

 

[royinidaho]

jeez, I always wanted to be smarter than somebody ..... but I don't thing this is the time /ubbthreads/images/graemlins/grin.gif

Back 'in the day' I modified some dies and made it so that my 222 REM light gun needed no resizing to hold the bullet. That would be the only condition I would thing that this is a good thing.

should you always be able to insert a bullet into a fired case by hand? Id say the short answer is yes.

Any possibility tat the case(s) are too long and stretching is grabbing th bullet upon firing?

 

[goodgrouper]

What is the neck diameter of your loaded round and what is the neck diameter of your chamber?

 

[Ridge Runner]

GG, loaded round neck diameter is .290, have no idea about chamber dia, I asked the smith to look at his reamer print and let me know.
anyone know a safe min. neck thickness?
JS

 

[Ridge Runner]

Roy, I asked the smith about brass length, he said trimming wasn't needed, so all I do is square the case mouths.
JS

 

[Waltech Jim]

James,

I have run into a somewhat similar problem. And my thinking was that there could be three reasons, if you have eliminated the "too thick brass in the neck" reason.

1. It was chambered with a tight neck, (you need to get the reamer dimensions as per GG above).

2. Your pressure is too low and the necks are springing back to the original dimensions.

3. Or you need to anneal the case necks. (take a couple of cases and anneal and shoot and see if it helps)

BTW, trimming to length is not the same as case neck turning. If cases are shot and reloaded they usually grow in length and need to be trimmed. I can't understand your smith's comment on case length.

Jim

 

[goodgrouper]

[ QUOTE ]
anyone know a safe min. neck thickness?


[/ QUOTE ]

There is no such thing as "a safe min. neck thickness". I have guns that have .008" thick necks all the way up to .014" thick. The .008" necks are just as safe as the .014" necks. The difference is the .008" are very easy to dent.

What I think you are trying to be concerned about is neck clearance. This is the chamber neck dimension minus your loaded round diameter. If it is a hunting rifle and you're not anal, you need probably at least .003" of clearance. On a bench rifle, I like running .001" clearance to .0015" although I have one hunting rifle that runs these tight clearances. I have to check it and clean it very often and it never goes on an atv or horse without having a sock put on it so it keeps dust out of the chamber. /ubbthreads/images/graemlins/shocked.gif

Back to the problem at hand: Your neck is .290 and your bullets don't have enough room to go back into the case? Did I read that right? If this is the case, your chamber dimension might be very close to .290 and your are running to tight of clearance and/or using too light of a load with it and/or your brass is naturally soft and has lots of "springback" and is basically closing up the hole and not letting a bullet go back in easily. You need to find out the neck diameter of your chamber before you fire any more shots through that rifle!

 

[Ridge Runner]

Jim, I think the smith goes by the standards that the sharp shoulders and very little body taper holds back case stretch and if your running moderately high pressures you'll lose primer pockets before the length needs to be addressed.
I'm a fudge over a max load with this powder and a 2 gr increase will deprime the cases, so its not under pressure.
I'm sure its chambered tighter than most rifles but this guy has built alot of rifles for the pa 1k bench rest club, and what I've told you is what he's told me. could just be something I do thats different I don't know.
I know that removing .002 from the casenecks resulted in less pressure with 1 less grain powder charge and 200 fps increase in MV
JS

 

[Ridge Runner]

gg, you read it right, I can take a loaded cartridge, and a fired one and I must use alot of force to push the fired cartridge over the protruding bullet of the loaded one.
after taking .002 off the neck, they measure .013 on one side and .014 on the other, think I see how it goes to even a coule up and try it there.
the smith said this case from locking the die down in the press, he suggested an 0-ring between the press and the lock ring, personaly I think its the spring clip that hold the shellholder in place on the rockchucker press, lots of folks have trouble with them. I use a larger shellholder for seating bullets to hold run-out to a min.
JS
JS

 

[Fiftydriver]

How many firings are on those cases. I bet if you anneal them you will get more consistant expansion if the cases have a few firings or more on them.

Kirby Allen(50)

 

[Ridge Runner]

kirby, the cases have been fireformed and fired a max of 1 time. would they allready need annealing?
I did notice all my casenecks are uneven, I turned a couple down to .010" that evened them up.
JS

 

[Fiftydriver]

I would not think they would need annealing already but it may be worth a try. Conventional wisdom would say they should not need it.

You had to turn your necks down that much just get them even???? Wow!!!

Kirby Allen(50)

 

[Ridge Runner]

ok, turned 5 cases to .010 neck thickness, loaded with 60 gr re22, with .012 neck thickness this load ran 3250 fps, at .010 they chrony's 3206, 3203, 3204, 3219 with no pressure signs. What now go up 1/2 grain and see if I can pick up any velocity?
I can now slip a bullet into a fired case with about .001 clearance
loaded rounds mic .285 fired ones .288 to .289. 2 of the five I loaded were a lil loose in the pockets but none blew the primer, I am however getting just a bit more cratering than I was with .012 necks.
JS

 

[Ridge Runner]

yeah kirby on the initial resizing I could see the difference in the false shoulder, the smith said its from tightening the die down tight against the lockring, I'm thinking the spring clip in the rockchucker that holds the shellholder may hold the shellholder out of alignment, I plan on removing it and replacing it with an o-ring I've heard this helps here's a pic of the false shoulder, you can see its only on one side

JS