Case mouth flaring....

[GT Accuracy]

Hey guys. I had something interesting happen today.

Necking down new 6.5 Creedmoor small FP brass to 6 Creedmoor has left me with some rather large case mouth flaring. Things I have tried...all have flaring:

• Ran 6.5 Creedmoor Brass through a non-bushing FL die. Flared
• Ran 6.5 CM brass through a bushing die with no bushing - Brass was not touched
• Used .270 bushing 1/4 of the way down the neck - flaring was staring. Completed the pass to 70% of the neck - Flared
• Used .268 bushing same as above - Flared.

Any thoughts? yes all my bushings had rattle they were not locked in by the die cap.

 

[Milo 2.0]

I've only got flaring when using a bushing die necking down, usually here a reg fl works, try running an expander down a couple, then retension with the .270 bushing.

 

[GT Accuracy]

yeah, i was thinking of running back up to 7mm and then step them down to 6.5 > 6mm but i worry about work hardening them some. I am curious if Lapua over annealed them and made them too soft so when they go into the neck sizing process they are extruding back up into the mouth

 

[Milo 2.0]

yeah, i was thinking of running back up to 7mm and then step them down to 6.5 > 6mm but i worry about work hardening them some. I am curious if Lapua over annealed them and made them too soft so when they go into the neck sizing process they are extruding back up into the mouth

I did the same thing you are trying with Lapua brass, came out fine. I used a Redding neck die w/o the expander, then set tension with a .241 mandrel. What are you using? I'd send you my setup if you'd like.

You do realize we've outed ourselves here?

 

[Milo 2.0]

yeah, i was thinking of running back up to 7mm and then step them down to 6.5 > 6mm but i worry about work hardening them some. I am curious if Lapua over annealed them and made them too soft so when they go into the neck sizing process they are extruding back up into the mouth

I guess if you can decipher if they are over annealed, work hardening them in some fashion may cure this.

 

[GT Accuracy]

I did the same thing you are trying with Lapua brass, came out fine. I used a Redding neck die w/o the expander, then set tension with a .241 mandrel. What are you using? I'd send you my setup if you'd like.

You do realize we've outed ourselves here?

I have used this strat with other lots of Lapua 6.5 creedmoor brass w/ no issues and no issues with hornady brass.

 

[GT Accuracy]

Could just be memory also... I’ll reach out to Speedy

 

[earlcurtis67]

Tagging in

 

[dkhunt14]

yeah, i was thinking of running back up to 7mm and then step them down to 6.5 > 6mm but i worry about work hardening them some. I am curious if Lapua over annealed them and made them too soft so when they go into the neck sizing process they are extruding back up into the mouth

If anything I would think under annealed. When I annealed Dasher brass too hard and fired them, they stayed against the chamber and didn't spring back. The next firing without annealing and they were ok. I would anneal one piece and try. Matt

 

[rardoin]

Greg, I had the same experience necking down Lapua 6.5 Creed to 6 Creed. Annealing the new cases prior to necking down 'almost' eliminated the issue completely. After the first firing they behaved normally.

 

[nmkid]

I had the same problem a few years back going from 6.5-284 to 6-284. A small step but, using Lapua brass was giving me the flare. Ended up as stated before, using an expander mandrel to get rid of most of it. As noted by rardoin it goes away after the first firing.