Hope bullet sorting will make setting CBTO easier

[RemingtonAI]

For one, I highly recommend the RCBS Precision Mic for measuring CBTO. Also, I just started polishing the inside of the necks with steel wool like Dmoran mentioned. Wow, what a difference! The bullets seat so much nicer and I didn't change anything dimensionally at all. And thus, there is even less variation in overall length because of it. I just chucked up a .22 cleaning brush with steel wool wrapped around it in my mini lathe and it doesn't take any time at all. Can't believe I didn't try this sooner. Jesse

 

[Linko]

being as I am learning......I see some clean inside with steel wool and others that dont recommend inside cleaning. I think we are trying to get optimal grip. correct? does SS pin and soap or dry media work best for case cleaning?

 

[dmoran]

@Linko -
Just a heads-up on my polishing routine to case necks: I start out new brass by polishing the inside neck after the chamfer step. When ever I trim and chamfer, I do it again. In between I leave the necks carbon and brush them to polish the carbon some. And regardless feel I get more consistent carbon layer of the necks by having them polished under the fouling, there for more consistent neck tension and bullet release.
Donovan

 

[Linko]

@Linko -
Just a heads-up on my polishing routine to case necks: I start out new brass by polishing the inside neck after the chamfer step. When ever I trim and chamfer, I do it again. In between I leave the necks carbon and brush them to polish the carbon some. And regardless feel I get more consistent carbon layer of the necks by having them polished under the fouling, there for more consistent neck tension and bullet release.
Donovan

besides your inside neck routine do you also tumble the brass or just wipe them down? I lube the brass with lanolin so I need to perform some cleaning to get off the lube?

 

[dmoran]

Besides the neck routine you just described, Do you also clean by tumbling or just wipe them down?

Primarily I just wipe them off between firings/cycles. When I do clean them, I use an ultra-sonic cleaner, but only if they have been sitting around a while to get out the internal erosion contamination that forms when sitting over lengths of time.
Donovan .... Edited in later: yes, all lube should be wiped or cleaned off - IME

 

[Brians356]

To OP: How large a bullet jump do you expect to employ? Jammed, a couple thousandths, .020", ... ?

Suppose your loads' CBTO varies by as much as .003". How much larger do you reckon that would make your five-shot groups at 100 yards than if you had (theoretical) zero CBTO variance?
-

 

[Linko]

To OP: How large a bullet jump do you expect to employ? Jammed, a couple thousandths, .020", ... ?

Suppose your loads' CBTO varies by as much as .003". How much larger do you reckon that would make your five-shot groups at 100 yards than if you had (theoretical) zero CBTO variance?
-

Appreciate your input. I am new so i am learning by trial and listening to advice here. Many of you have tons more experience than I do.
I am trying to do two things, find a seating depth that works in my gun and have a consistant distance to the lands (TBD) for each round I load.

 

[Brians356]

Appreciate your input. I am new so i am learning by trial and listening to advice here. Many of you have tons more experience than I do.
I am trying to do two things, find a seating depth that works in my gun and have a consistant distance to the lands (TBD) for each round I load.

Using a Redding Comp seater and measuring CBTO w/ Hornady gauge, I can get the measurements to within < .001", without chasing back and forth. But I am not using VLD bullets. What variance are you trying to achieve?

My question about bullet jump was based on the concept that a CBTO variance of, say, .002" is fairly innocuous if you are jumping .020", but if you are trying to seat just touching, or just shy of touching, the same variance is quite significant. Which is a main reason I now try to find an accurate jump somewhere in the .020" to .030" or larger range, or even greater if required to mitigate magazine length restrictions in walk-around hunting rifles.
-

 

[dkhunt14]

Using a Redding Comp seater and measuring CBTO w/ Hornady gauge, I can get the measurements to within < .001", without chasing back and forth. But I am not using VLD bullets. What variance are you trying to achieve?

My question about bullet jump was based on the concept that a CBTO variance of, say, .002" is fairly innocuous if you are jumping .020", but if you are trying to seat just touching, or just shy of touching, the same variance is quite significant. Which is a main reason I now try to find an accurate jump somewhere in the .020" to .030" or larger range, or even greater if required to mitigate magazine length restrictions in walk-around hunting rifles.
-

This is not all true. In my experience and from guys like Tom, the difference between setting records and shooting good can be as little as .002 to .003 in seating depth. So a .002 to .003 variance in seating depth in ammo would show. This is even counting bullets in the lands between .002 to .005. You would think being in wouldn't matter but it does. Now this is guns shot at 1000 yards and proven in competition. Will you see it at 100 yards, probably not, but it shows on paper at 1000. Matt

 

[Linko]

I am just trying to get the jump or jam the same for groups I am loading. New rifle new shooter new loader, thats me. Goal get good enough to shoot MRP and get them all on the paper in some kind of group. If I can do that, them I can learn to shoot better.

I sorted a 500 round box of berger 105 hybrids. cleaned my fired lapua brass by wiping them down, lubed, FL sized, tumpled dry media, wiped clean and brused the necks. Should I use steel wool inside the necks or just load? (whidden seater in CO-AX)

 

[Brians356]

New rifle new shooter new loader, thats me.

Q.E.D.
-

 

[Linko]

loaded my first sorted bullets that measured closely. much easier getting the loaded rounds equal, much less back and forth with die settings. also seated as evenly as possible with my coax press. will look into a arbor/inline combo next.

 

[wolfman]

thanks for the input gents. I spent a bunch of time last winter sorting 3500+ juggernauts base to ogive, and then pointing them. It really didn't make sense then , and it still doesn't! Sorting by OAL prior to pointing seems much more logical. My plan is to follow that up by sorting with a Bob Green tool, and hopefully call that good.

 

[nfa1eab]

In my 6 BRX I use a worn out brush wrapped with 0000 steel wool mounted in a cordless drill and after trim, debur, chamfer, I run the drill and slide the cases onto for a light polishing. Removes carbon and roughness from the chamfer and debur step, and lightly polishes the inside of the neck. Bullets seat very smoothly and uniformly. I use moly'd bullets and after seating, if I have to pull them with an iinertia puller, there are no scratches in the moly. Works for me. A little messy working with steel wool, but gives a nice smooth neck. Make sure to remove all remnants of the steel wool from the case.