Brass flow into necks ?

[rsbhunter]

Was wondering if in my 6 Dasher cases need to be neck turned again after x number of firings ? I only skim necks anyway to about 70% - 80% clean up. I'm not stomping on the loads, 32.0 gr Varget with 105s...I do trim, anneal, brush each time.....rsbhunter

 

[std7mag]

Probably wouldn't hurt.
Brass only has one way to go.

 

[rsbhunter]

That's what I was thinking .....thanks for the reply...rsbhunter

 

[gunsandgunsmithing]

If the bullet isn't being seated below the donut area...forget about it. If it is, get rid of it. But ulimately, a longer freebore that prevents the bullets being seated that deep in the case is best, whenever possible. The only real exception to that is when mag length is the limiting factor. If the necks are thickening..again, different reamer or yes, keep them to a diameter that allows clearance

 

[rsbhunter]

Body/boattail junction is at neck/shoulder junction or just slightly above...no donut problems. Just figure that even @ 1.5-2 thou shoulder setback, the pressure to expand and stretch case to fill chamber would result in brass flow into the neck area...rsbhunter

 

[gunsandgunsmithing]

Body/boattail junction is at neck/shoulder junction or just slightly above...no donut problems. Just figure that even @ 1.5-2 thou shoulder setback, the pressure to expand and stretch case to fill chamber would result in brass flow into the neck area...rsbhunter

Non-issue. Most brass migration is a result of the sizing operation and proper die or bushing selection...not pressure. Work the brass minimally and have ample clearance...and forget about it. If you're looking to get 50 firings from your brass, or something fairly extreme...then monitor it over time but your concern is not pressure but proper die selection.

 

[JEFFPPC]

Non-issue. Most brass migration is a result of the sizing operation and proper die or bushing selection...not pressure. Work the brass minimally and have ample clearance...and forget about it. If you're looking to get 50 firings from your brass, or something fairly extreme...then monitor it over time but your concern is not pressure but proper die selection.

Maybe for the first time I must disagree. If you use a tenth Mic on your loaded rounds you will see them fatten up. About every 5 th firing I run the knife back over them. Some you see nothing, some you see dust, every once in a while you say, Wow. I run a tight neck tight so I stay on top of it. I feel it pays off. Remember it's the little things plus the flags that help you be sucessful.

 

[6BRA]

Maybe for the first time I must disagree. If you use a tenth Mic on your loaded rounds you will see them fatten up. About every 5 th firing I run the knife back over them. Some you see nothing, some you see dust, every once in a while you say, Wow. I run a tight neck tight so I stay on top of it. I feel it pays off. Remember it's the little things plus the flags that help you be sucessful.

Couldn't agree more..the bushings will push brass the opposite direction towards the donut. I quit using bushings for this very reason!

 

[mikecr]

I turn all necks, and neck size only with bushings. There is never any donut building for me.

Brass does not 'flow' into necks. It moves per sizing, thick towards thin.
And neck bushings do not cause donuts.
It's FL sizing that rolls brass thickness up cases (always up), eventually into neck-shoulder junction, and leading to trimming as well.
No matter how many reload cycles, I don't have to trim (beyond initial, or ever).

 

[6BRA]

I turn all necks, and neck size only with bushings. There is never any donut building for me.

Brass does not 'flow' into necks. It moves per sizing, thick towards thin.
And neck bushings do not cause donuts.
It's FL sizing that rolls brass thickness up cases (always up), eventually into neck-shoulder junction, and leading to trimming as well.
No matter how many reload cycles, I don't have to trim (beyond initial, or ever).

Will your mic measure ten thousandths or 100 thousandths? If it only goes to .001...you won't understand.

 

[6BRA]

Both Mitutoyos, 1 of them is useless imo.

 

[JEFFPPC]

Will your mic measure ten thousandths or 100 thousandths? If it only goes to .001...you won't understand.

4 decimal points. .0001 Don't get technical, I am not a machinest, lol. I won't argue why but I will tell you....necks thicken. When you talk about pressure don't neglect intense heat. Does that enter in. I don't know....But how can it not? I do know in this sport in my opinion there are a lot of 'facts' that are accepted but not verified. I do know thin necks are out of favor so there are lots of reasons/excuses to not 'need' them. I just know what I see and what works for me. I am willing to do the work if I think it helps me. Bottom line....he who reads the flags best.....wins. I do not like digital mics..

 

[SKWERLZ]

Was wondering if in my 6 Dasher cases need to be neck turned again after x number of firings ? I only skim necks anyway to about 70% - 80% clean up. I'm not stomping on the loads, 32.0 gr Varget with 105s...I do trim, anneal, brush each time.....rsbhunter

You should watch the (edited) Jack Neary interview cortina did on BR brass prep
Interesting and revealing.

 

[Bill Norris]

You should watch the speedy interview cortina did on BR brass prep
Interesting and revealing.

Link Please ?

 

[SKWERLZ]

Link Please ?

Correction
It was with Jack Neary

The stuff on neck turning is pure gold
Erik does a good job relating F class requirements and that can be applied to field use obviously.

 

[Bill Norris]

Correction
It was with Jack Neary

The stuff on neck turning is pure gold
Erik does a good job relating F class requirements and that can be applied to field use obviously.

Oh yea I have seen this one. Great video no doubt.

 

[6BRA]

Oh yea I have seen this one. Great video no doubt.

I wish you wouldn't have posted that. Lol....I have been preaching this for a year or better. So many big names argue too...why do you think Speedys pumpkin patch is in excess of probably 50 by now? Every Pumpkin that comes up for sale, he buys!

 

[Bill Norris]

Correction
It was with Jack Neary

The stuff on neck turning is pure gold
Erik does a good job relating F class requirements and that can be applied to field use obviously.

Oh yea, I'm pretty sure Jack has been around the block enough times that he knows a few things that work and some that don't. He also does a neat powder/seating depth combo test in another video that I plan to try once I get my 6PPC in hand.

 

[SKWERLZ]

Oh yea, I'm pretty sure Jack has been around the block enough times that he knows a few things that work and some that don't. He also does a neat powder/seating depth combo test in another video that I plan to try once I get my 6PPC in hand.

Absolutely!

The talk about trimming in I think the second video correlated perfectly with a sniper ammo test Jeff siewart did on case mouth conditions affecting accuracy
Accurate trimming and chamfering are big factors for accuracy.

 

[WyleWD]

Maybe for the first time I must disagree. If you use a tenth Mic on your loaded rounds you will see them fatten up. About every 5 th firing I run the knife back over them. Some you see nothing, some you see dust, every once in a while you say, Wow. I run a tight neck tight so I stay on top of it. I feel it pays off. Remember it's the little things plus the flags that help you be sucessful.

+1^^^ My observations mirror what JEFF is seeing. I start measuring a few after the third firing and by the 4th or 5th firing it's time for a trim to length and re-turn usually. JME. WD