Case length question

[17cal Fan]

Loading ammo for an upcoming PD trip. Got around to loading for the 17 Fireball came across something weird. I use a busing die and understand the neck tension considerations but I'm getting a case mouth that is not perpendicular to the next. Visible with the naked eye.

From what I can tell, it's only the 221 Fireball brass that was necked down to 17 (with the proper form die). Bottom line, if I trim the case enough to be perpendicular I end up at 1.375 on some of the worst ones which is .025 under trim to (1.40).

My question then is aside from being short and losing a little bullet contact, is this a huge issue to go ahead and trim them?

This a round left over from last year, so apparently it was going on then and I missed it. Don't recall the PD's having an issue exploding with this ammo.

 

[K22]

I actually had a batch of Remington virgin cases where several cases had the same issue, the case mouths were not parallel. I can't recall how many thousands off they were, but it was visible to the naked eye, like yours.

I trimmed them all to a uniform length and they worked fine.

 

[DirtySteve]

Trim them.. And don't look back.... Worst case is you get a little more carbon build up.

 

[Bill Norris]

Trim them.. And don't look back.... Worst case is you get a little more carbon build up.

Agree. A little extra cleaning the throat area but nothing major there.

 

[17cal Fan]

Thanks, I did go ahead and start trimming crossing my fingers that it was the right thing while waiting for advice. It's just strange, never noticed it before.

 

[sqrlgtr]

Loading ammo for an upcoming PD trip. Got around to loading for the 17 Fireball came across something weird. I use a busing die and understand the neck tension considerations but I'm getting a case mouth that is not perpendicular to the next. Visible with the naked eye.

From what I can tell, it's only the 221 Fireball brass that was necked down to 17 (with the proper form die). Bottom line, if I trim the case enough to be perpendicular I end up at 1.375 on some of the worst ones which is .025 under trim to (1.40).

My question then is aside from being short and losing a little bullet contact, is this a huge issue to go ahead and trim them?

This a round left over from last year, so apparently it was going on then and I missed it. Don't recall the PD's having an issue exploding with this ammo.

just curious what brand of brass because I have also seen this with Remington brass...

 

[17cal Fan]

Both Remington and Nosler 221 brass have behaved this way. Using coated bushings so I don't think that's the problem. Not sure why it is happening.

 

[Kracken McGraw]

Even if you didn’t trim them even, I bet your barrel will send them out straight.

 

[17cal Fan]

Even if you didn’t trim them even, I bet your barrel will send them out straight.

I'm sure some of them went in the pipe that way last year. I am kinda OCD about stuff but I've read often that EVEN neck tension is important. Probably not for PD's.

 

[Kracken McGraw]

I'm sure some of them went in the pipe that way last year. I am kinda OCD about stuff but I've read often that EVEN neck tension is important. Probably not for PD's.

But if the bullet is in the neck a reasonable distance, wouldn’t the neck tension still be even till the powder explosion expands the brass and releases the bullet?

 

[fkimble@charter.net]

Did you chamfer the outside of the case mouth before necking down?

Frank

 

[SeabeeKen]

Even if you didn’t trim them even, I bet your barrel will send them out straight.

Would make an interesting test to check for difference in accuracy. I trim mine just enough to true them but also make them all a uniform length. Just watch for a carbon ring

 

[17cal Fan]

But if the bullet is in the neck a reasonable distance, wouldn’t the neck tension still be even till the powder explosion expands the brass and releases the bullet?

That makes sense but I've read that cases should be trimmed all to the same length for accuracy (consistency). And this 221 brass is somewhat shorter than 17 fireball brass to start with. I hated losing any length because I'm not seating very deep. Just off the lands suits this rifle very well.

 

[17cal Fan]

Did you chamfer the outside of the case mouth before necking down?

Frank

No I did not. Would that help? This is my first set of bushing dies, still learning.

 

[Steel Mover]

Be careful, carbon buildup in front of the case mouth for brass cut too short, can easily create an over pressure situation when a full length case is chambered and fired, after several short cases are fired, even at a starting load. I ended up having to clean up such a chamber, with a reamer. Carbon buildup in front of a chamber can be tough to remove.

 

[markm87]

I actually had a batch of Remington virgin cases where several cases had the same issue, the case mouths were not parallel.

I remember years back buying the baggies of new Win Brass in store at Cabela's, and that crap was so bad you could see it with the naked eye.

 

[K22]

I remember years back buying the baggies of new Win Brass in store at Cabela's, and that crap was so bad you could see it with the naked eye.

I almost always for about 5 cases in each bag of Win virgin cases that could not be salvaged due to cold laps in the shoulder and neck area. Back then, it was just an annoyance, these days with prices skyrocketing, its more significant.