bullet doesn't fit fired case

[Link]

Bullet wont fit in fired case neck. A loaded round chambers fine. How much accuracy am I loosing? Should I give it a light turn?
thanks Don

 

[FatBoy]

I'd say, it depends. I have this with Norma Dasher brass so I skimmed 50 cases and tested them side by side at 600. Zero difference. Everything was within normal group size. size by side and mixed made no difference in my circumstance.

You're going to have to put some time in testing IMO.

 

[jepp2]

Bullet wont fit in fired case neck. A loaded round chambers fine

What is the neck diameter on your rifle, and the loaded round neck OD?

 

[Preacher]

How many times were the cases fired ?

 

[Dusty Stevens]

Its not the accuracy youre losing its the extreme pressure youre going to encounter when your necks get thicker and the pressure ring on the bullet gets big

 

[Link]

What is the neck diameter on your rifle, and the loaded round neck OD?

chamber- 268
loaded- 264
fired round neck- 266
4 fires on brass

 

[mikecr]

That's tons of clearance.
If the bullet is just stopping on donut area (near neck-shoulder junction), then it's only a problem if you make it a problem.

 

[chop house]

i am watching this thread closely. i have same issue when using short for caliber bullets barely seated (like 0.060") into the case. i suspect the issue could be similar with typical length bullets in long freebore. i began troubleshooting by: 1. annealing every time, not sure of the affect. 2. seating bullets deeper which definitely helps the seal and expands the necks. 3. attempting to find a higher node but i am near book max with the expected velocity.

i would add that in my case the donut is nowhere involved.... bullets can not even get started in fired brass. the brass is typically all trimmed to -0.010" under max. btw, to gain a little more length i am 4. not trimming back, leaving at book length.

 

[243winxb]

Slow powder, light bullets, from starting to midrange loads , doesn't expand the necks fully in my 243 win.

68gr Bergers/Sierra 70gr will not go in the case mouth of fired brass when using IMR 4350 or 4831, till i load near maximums. Factory chamber.

 

[chop house]

oh, also add to my list: 5. experiment with similar weight bullets in flat base instead of boat tail....

 

[Dusty Stevens]

Does the bullet go in there but stop at the base or not go in the neck at all?

 

[jepp2]

Slow powder, light bullets, from starting to midrange loads , doesn't expand the necks fully in my 243 win

Agree. On my 25-06 using RL 19 even with loads in the low 60K PSI, the necks aren't expanded enough at the mouth for a bullet to enter. And this is a factory neck with tons of clearance.

 

[Link]

Does the bullet go in there but stop at the base or not go in the neck at all?

I don't believe it's a donut, it doesn't start at all. These are BT bullets. Once seated it is hard to pull the bullet from the neck not sized.

 

[jds holler]

Seems to me that there are a half dozen reasons why you might have this situation. The only one which may be a problem would be if your chamber neck diameter is too small to allow neck expansion at detonation. All the other reasons present no real problem. jd

 

[alinwa]

Seems to me that there are a half dozen reasons why you might have this situation. The only one which may be a problem would be if your chamber neck diameter is too small to allow neck expansion at detonation. All the other reasons present no real problem. jd

I can speak from experience.... even if the neck RUBS (Allie Euber calls it "scuff fit") it won't affect pressure unless it gets long enough to crimp. It doesn't have to actually expand and release...... I shoot a lot of rifles with "fitted necks".

 

[luckyshot52]

IMHO donuts can cost accuracy. Tested 6ppc cases that developed donutversus same batch that didn't. Definite accuracy loss with the debuted cases. Even after removing some and re- testing.

 

[Uncle Ed]

What type sizing die are you using, bushing, Lee Collet, standard full length die with expander.

I noticed the same thing on some of my cases and its just the very end of case mouth that is a smaller diameter than the rest of the neck. Is this a reaction from firing the case or sizing and the case mouth closing to a smaller diameter?

I know you said the bullet will not fit in a fired case but is it just the case mouth that is smaller in diameter?

If you look at jepp2 photo the case mouth looks tapered, could this be for some reason the chamber pressure not pressing the case mouth against the chamber. Or pressure leaking past the case mouth and making the case mouth smaller. (see 243winxb and jepp2 postings)

 

[Link]

I'm using a FL die with a neck bu. This isn't just the end of the neck, I just champher ed the bejeepers out of a neck and still no slip fit. If it doesn't hurt accuracy the heck with it lol.

 

[Uncle Ed]

I'm using a FL die with a neck bu. This isn't just the end of the neck, I just champher ed the bejeepers out of a neck and still no slip fit. If it doesn't hurt accuracy the heck with it lol.

If jepp2 photo and its tapered case mouth is any idea you would need to trim the case at least 1/8 inch to clear the taper.

To reduce the tapered effect I used a expander die on the case neck, but it still springs back slightly.

I even tried a Lyman type M expander to ease bullet seating effort and reduce any bullet runout.

I would just like to know 100% what is actually causing the case mouths to be tapered.

 

[anschuter2013]

My 30BR was chambered with a .330 neck reamer. Loaded rounds measure .328 OD.

After firing, the brass neck ID will not accept a slip fit with any popular 30 cal. bullets such as BIB, EPS, Hillbilly or Speer.

It shoots great though.