Playing with brass for precision ...

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Tikka223

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I've been doing some reading on brass ... I noticed when doing some hand loads that some bullets seated with less resistance than others. I started wondering about all those tools out there; neck trimmers, case turners, etc.

I read the following article and WOW this can be a really anal task.

http://www.6mmbr.com/jgcaseprep.html

I already use the chamfering tool on new brass. I've been thinking of turning?/trimming? the brass to same length. Is this going to give me any kind of noticeable effect on group size?

I'm thinking of length first because it seems to involve less equipment.

Thoughts?
 
precission is a game of consistancy, poweder charge, bullet weight, brass capacity volume, neck tention , bullet concentricity and the list goes on,

every thing you do will make a very small change in accuracy, but doing multiple things (correctly of course) will make a BIG differance in accuracy.

brass should always be trimmed to the same length and below the "max OAL" neck turning will true the necks up and provide more even neck tention..


will you see an improvment... maybe a very small one, IF you are a good shot.. will the average joe at the range see a differance, probably not,
 
Neck Bushings

Get yiourself a set of dies that use bushings for controling neck demensions. I personally use Wilson hand dies. I seat a bullet into the brass, measure the neck and then use a bushing 1 thou smaller. Once everything is re-sized I then run it through a expander mandrel in the appropriate caliber size. Makes it always consistant. When using the expander if it doesn't feel "right" it gets tossed into my rehab box for annealing. Ive done the neck turning thing and it didn't make enough of a difference for me to bother and its a pain when you need 300 pieces of brass ready to go. Good luck, Piper.
 
Run away before the OCD sets in.... I used to laugh at people that did all this measuring and trimming, sizing and uniforming.

Next thing you know you own 37 tools just for uniforming cases and you need 2 or 3 hours to prep 50 pieces of new brass, but only 42 will make the cut anyway...:runaway:
 
A couple of articles also worth reading.

Google - Rifleman's Journal
See - December 2009 and October 2009 concerning neck tension and turning.
 
timmy204 said:
The biggest thing i've found for consistent neck tension is properly annealing your case necks.
Click to expand...

Bingo, this is very important and a lot of shooters overlook this process.

This will certainly make or break a group from my experience, depending on the type of die used brass necks will work harden much faster with regular FL dies and expander ball.
If you use a bushing die with the correct size bushing the brass will take much longer to work harden [may more firings] .

It is also important for your necks to be uniform in thickness so skim turning necks is the best way to make them all the same.

I have bought brand new brass [not lapua] that needed annealing right out of the bag , when you seat bullets and they all feel a little diferent in seating pressure this does not lead to good grouping.
And of course having your brass sorted by weght 1 gr or less is a good idea and like some others have said trim to length.
 
First things first.

1 - are you using high quality, consistent brass?

You need to have reasonably consistent neck wall thickness. You can achieve this buy buying uniform brass (out of the box Lapua usually is, though this is never guaranteed), or you can "fake it" to a certain extent, by fixing-up your brass (e.g. neck turning), though this can be quite a bit of work.

2 - are your dies establishing consistent neck tension on your brass?

Using standard dies with an expander ball is usually "the wrong thing to do", though if you make sure the expander button or inside of the neck is consistently lubricated for each case you can often get good enough results. Another way to get good results is to use a Lee Collet Die (they'll produce reasonably good results even with fiarly nonuniform neck thicknesses). Or to use a bushing die (they'll give you great results, but they really need you to have uniform neck thicknesses).
 
Right now I'm using Winchester .223 Rem brass, bought it new and cleaned up the neck with a champher (spelling?) tool. I don't full length size for my bolt guns, once fire-formed I use the Lee collet neck die. For seating the bullets I use the Forstner BR die.
 
Hmmm, that's odd. Winchester brass is usually pretty good quality. If you've chamfered the case mouths, and are using a collet die (unpleasant to use, but gives good results), and seating with the Forster BR die (really good piece of gear), I would expect you to be seeing very good consistency in the amount of force needed to seat a bullet.

I assume that at this point your brass is clean, and you don't have any bits of case lube on the inside of the case mouths (or anywhere else for that matter)?

The bullets that you had that seated with less resistance - were they only a bit easier to seat, or were they crazy-easy to seat?

My complaint about the Lee collet die is that I've found that I never get any sort of "feel" as to whether or not I have sized the neck down, or not. It always seems to be a "hard" stop.

Something you could try next time you're loading and you get to an easy-to-seat case or two, perhaps you could mark them and set them aside. Pull the bullet, dump the powder, and run them through your collet die again. Try seating (in the un-primed and un-powdered case) the bullets that you pulled. If they seat easily, pull them and try seating new bullets - does a different bullet seat differently?
 
Tikka223 what kind of press do you use ,does the press cam over.
If it does not using a collet die might not be such a good idea as you will always be putting different tensions on the necks.

A friend of mine has a lee press not sure what model but it does not cam over so I would think it would be hard to use a collet die in a press like trhat.
 
I polished down the Lee Collet center stem a couple thou, then run my sized cases through a "m" die, dimensioned to open the neck back up to two thou. of neck tension.
The collet works best for me set up to run the ram handle over center, then a 1/4 turn of the case and repeat. Also, a washer betweem the shellholder and die bottom moves the sized portion of the neck away from the shoulder, so there is no movement of brass anywhere that it can affect the fit of case to chamber. (some collet's can move the neck down into the shoulder, causing tight chambering.)
Seated with Redding BR die.
The above setup stays under 1.5 thou. runout, measured well out on the bullet ogive, with lapua brass unturned.

Annealing every half dozen loadings helps keep everything nice and consistent.

Lost count of how many times my cases have been reloaded, ... plenty, .... they just keep chugging along, long as you don't load too hot and open the primer pockets;)
 
outof remington, winchester, fedreal brass i find Fed Brass are the better quality out of the 3. depends on what you shoot, if for 30-06 or non mag load, most will be fine with less stratch.
I do shoot 300/338 rum, 338wm, 30-378 and with those, these 3 bradd seem to stratch alot after one or two shots..
I did go with Nosler brass, yes it is more money but very quality built case.. or if you dont mind spending little more, lapua brass are also nice.
 
Using the RCBS Rock Chucker press. I think I know what you mean about gaming over and no, I don't think mine does, I think it's set up so that the stroke bottoms out just before the linkage starts to go backwards.

I as for the case lube, I don't use a ridiculous amount but I will lube the case on a pad before running them through the press.

The issue with seating the brass is most notable with new brass but I have seen it with fireformed brass. Anything from the collet not closing the neck enough to it feeling quite tight. I'm wondering if I should set up the collet for so I can put more force on the case.
 
Yea if you think Lapus is too much then Nosler works good too... but if you shoot alot, then i'd go with lapua... in long run you save $$ and time
 
Tikka223 said:
Using the RCBS Rock Chucker press. I think I know what you mean about gaming over and no, I don't think mine does, I think it's set up so that the stroke bottoms out just before the linkage starts to go backwards.

...............................................................................................................................................................................
... <Much solid advice in this thread, and as many different ways of doing the precision loading proceedure as there are individuals doing it.:)
To reply to OP, this is the way it works for me.

I don't shoot BR, my ammo standards are 1.5 thou. TIR or less, and 1/2 MOA from my 6.5x55 or .308 precision rifles. Shot from bipod/bag, in the field.

The reason cam-over works better than just trying for consistent handle pressure, is because cam-over does not vary ... the press is the same every time.

Far as I know, the Rock Chucker does cam over. Have a close look at the ram, with no die in the press, see if it reverses direction very slightly at the end of the handle stroke.
Collet's are Very Touchy to set up(ask fellow member Gootch, who's Rock Chucker once sent a Lee Collet aluminum top cap, clean through a ceiling tile!:redface:)
If it's the die's adjustment that is preventing cam-over, you need to back it off till it will, then make(very)fine adjustments by feel to find the sweet spot for sizing. Too much, and vertical ridges/impressions show on the neck. Too little, and neck thickness variations also vary the tension on the seated bullets. Some will be loose.
They aren't all perfect out of the box, dissassemble and look for burr's between the four fine slits in the collet piece, also rough surfaces on the two angled parts that force the collet closed. Also, some have fat center stems, that won't size enough. "Tuning" may be required.

I cycle mine through the die twice, with a 1/4 turn of the case between strokes. > ...

..................................................................................................................................................

I as for the case lube, I don't use a ridiculous amount but I will lube the case on a pad before running them through the press.

........................................................................................................................................................
... <I don't use any lube when loading with collet's.> ...


The issue with seating the brass is most notable with new brass but I have seen it with fireformed brass. Anything from the collet not closing the neck enough to it feeling quite tight. I'm wondering if I should set up the collet for so I can put more force on the case.
Click to expand...

.......................................................................................................................................................

... <With new or just-trimmed brass, mouth deburring matters. Try using the usual 45 degree cutter(lightly), then a shallow angle cutter very lightly(lyman), then a polish with some 0000 steelwool on an old bore brush, chucked in your drill/driver.
Pay attention to ram handle feel when you seat bullets, done right, ... no notchy, jerky, inconsistent force's will be apparent.
With that fine ForsterBR seater, they should be very straight.
Lapua cases are worth it, actually cheaper in the long run, 'cause your setup does not move the necks excessively(unlike the RCBS-type dies), and barring overpressure loads, 100 will out last a barrel, ... or two.:D

Annealing is indicated when seating feel starts to get inconsistent.> ...




Hope this helps.
 
rnbra-shooter said:
My complaint about the Lee collet die is that I've found that I never get any sort of "feel" as to whether or not I have sized the neck down, or not. It always seems to be a "hard" stop.
Click to expand...

True, the Lee Collet Die isn't the easiest to set up but it performs really well.

I use a Forster Co-Ax press and although it is not recommended to get near the cam over point, you can actually tune the die to close its jaws at that precise point, just before hitting the stop.

It demands very careful setting because the press is at its largest mechanical advantage and you can crush the die's fingers very easily, destroying it, but, if done correctly, you'll never have to worry about having sized the neck or not. Just place the brass on the shellholder, swing the lever to the stop and back, that's all.

Ah, one thing: before even trying to set up the Lee die, take it apart, degrease it, clean its parts and examine the slits in the collet; with a razor blade or an X-Acto, remove any machining metal debris or burr there.
Put a small dab of hi-pressure grease on the collet's ramp and screw evrything back.
PP.
 
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