New at rifle reloading - questions about brass trimming

[frumious]

I bought my first rifle in January 2011 - a Weatherby Vanguard in .308. I bought 100 rounds of Remington Core-Lokt soft point 150's and shot them all and have been reloading those same 100 cases for a few weeks now. I just shot my last round of the 5th or 6th batch of reloads. I only neck-size (Lee collet die) and I have never trimmed brass up until now.

On this last batch it seemed quite a few (10% maybe) of the rounds were either a little tough to close the bolt on or a little tough to open the bolt on. No sticky ejection though, and this load (43.4 gr AA2520 under a Hornady 168 boat-tail match) has never exhibited pressure signs, so it seemed it was time to trim brass. I measured a few rounds and they were all over 2.015.

So I trimmed to 2.005. And then chamfered/deburred. What a pain in the fingers. I have a Wilson trimmer mounted in a little portable vise.

Here are my questions:

• How much pressure do I use when chamfering/deburring? I figure very light pressure but I dunno.
• Does frequent trimming/chamfering/deburring contribute to shortened case neck life? Remember, I am neck sizing only and not crimping (bolt gun).
• If I decide to anneal case necks, how do I determine when the neck is hot enough to quench? One of those point-and-shoot thermometers maybe? Wait until the neck turns a certain color? Wait a set number of seconds?
• You use a propane torch to anneal, right? Can I just point it at one side of the neck or do I need to go all around? If I line up 10 cases it will be a pain to to around all of them; I'd rather just wave the torch back and forth up and down the line and then knock them all off into a trough of water or something.

Thanks in advance for the advice.

-cls

[PA-Joe]

The hard to chamber rounds may be too long a case/neck, bullet seated too far out, dirty chamber or it's time to set the shoulders back.

[steve4102]

You are going to have to FL size that brass sooner or later, looks like it's time.

[frumious]

I'm pretty sure the problem is 100% case length, as cases were measuring over 2.015", the max for this cartridge. COAL is 2.803, well under the max of 2.820. Also I have been cleaning with a few brush strokes every 10-15 rounds (load work-up) so I don't think it is dirt. For that matter, it is only some cartridges that have the problem, not all of them. Seems like dirt buildup would affect more cartridges.

On the hard-to-chamber rounds the shoulders were not deformed in any way. Don't believe I have any need to FL size.

-cls

[rsnell]

Chamber an empty case in your rifle. If the bolt closes without difficulty, the head space is still OK. If not, it is time the set the shoulder back using a full length sizing die. Use your rifle to set the die.

Bob Snell

[hornetguy]

multiple deburring sessions does not seem to work-harden brass, it just shaves it off. It seems like only repeated firings and sizings causes the work-hardening.
I would get one of the cheap Lee case trimming kits, and trim all the brass back to the same length. I chamfer the case mouth only enough to remove the "lip" left from trimming.

I have only annealed cases once or twice, but I put them (deprimed) in a shallow pan of water, to make sure the heads didn't get hot. I heated them one at a time, until the neck/shoulder area was fairly discolored, (not red hot) then tipped it over into the water. It seemed to work ok.

[Sevens]

I hesitate every time I post on a rifle-specific thread because I'm a handgun guy and though I'm set up for 5 rifle calibers, I just don't do a heap in handloading with them. I pretty much dabble.

So I suppose that's my disclaimer... I'm going to type some stuff and if it's TOTALLY WRONG, I'm sure someone will correct me, or at least expound on it so that some sense can be made from it. Maybe.

First off, when checking length, remember that you aren't getting a true picture of length until after you've sized it. Of course, you say that you are only neck-sizing, so your sizing doesn't alter the length, but if/when you full length size, it will alter the length, so measure after you've done it.

Also, it seems to me that a piece of brass that is merely too long in the neck isn't going to show much resistance to chambering --if-- you try to chamber it without a bullet in place. So I'd suggest chambering a neck-sized but not yet loaded piece of brass and see if you feel the same resistance that you are feeling right now.

Put a bullet in there and then try to squeeze a case with a long neck in to the chamber and it gets tight in a hurry. And in the event you didn't know -- this also raises pressure because the bullet has the chance of getting pinched. Not good!

Brass flows forward and as it does, we trim it. And as it does... that brass is coming from somewhere and we are trimming it OFF, so the brass is obviously getting a little weaker. It can't last forever.

I wouldn't say that frequent trimming in & of itself leads to shortened brass life... more like, frequent trimming is a sign of brass is that is being fatigued and will THUS have a short life. Either the brass flows too easily (cheap brass) or your loads are hot and the brass is taking the heat from it.

NOT trimming your brass can lead to problems. Minor trouble is inconsistency, which won't do you any favors in accuracy. Bigger trouble are the pressure concerns I mentioned above.

You should trim as little as needed to get by... but keeping everything consistent is your best shot at repeatable accuracy, if that's important to you.

I think in the end you'll find that yes, you do need to full-length size your brass eventually. And when that time comes, don't do just the pieces that "feel like they need it", do them all as a lot. Consistency, remember.

[frumious]

Thanks all. Sevens, rsnell, I have already trimmed them all so it will be a while before I can try the test of chambering with and without a bullet.

-cls

[Sevens]

Well, if you trimmed them... do they chamber now without a bullet, and without any resistance? If no resistance, then you should be good to go.

If you trimmed and they still offer resistance... then yeah, F-L size them.

[frumious]

Oh right, gotcha. I'll do that before I reload them again, probably this weekend. Thanks!

-cls

[Unclenick]

Frumerious,

Brass's yield strength is somewhere around 12,000 psi, IIRC, so any case you fire at over that pressure won't return 100% to shape. As a result, your cases grow a tiny bit each time you shoot and eventually get too tight to fit in the chamber. As the others said, you need to set the shoulder back. You can do that with your Lee FL die, but it will not give you the exact same neck tension as your collet die does and the expander can pull the necks off axis, so don't expect that particular round of loads to shoot as accurately as the others.

The other strategy is to use a Redding Body Die, or a full-length neck bushing type die by any maker and leave the bushing out. You can then set the shoulder back and still size the neck in the Lee Collet die, which makes a good accuracy combination. It's just two sizing steps instead of one.

You only need to push the shoulder back about a thousandth of an inch for a bolt gun. Many do that with every reload, finding the little bit of slop in the chamber actually allows a little self-centering that can prove to be more accurate in some guns than straight neck sizing. You'd have to try that in your gun to see if it happens.

Alas, you will likely have to trim again after body sizing. It usually flows some brass forward into the neck area. If it flows brass to form the dreaded internal donut at the neck and shoulder junction, you may need to run them over the collet die mandrel again.

Annealing of case brass is actually partial annealing. You want to stress-relieve the neck and shoulder brass, not make it dead soft. Letting it get red hot is too hot and that will weaken it. Ironically, when you overheat and weaken the brass that way, it will split in just a few reloads, so it requires annealing again every three or four reloads to prevent that. Ordinarily you wouldn't expect to have to anneal that often, as you've already discovered.

How far brass anneals depends on both time and temperature. The hotter it gets, the faster that happens. It takes about an hour at 570°F and about 20 seconds at 700°F to just stress relieve it without over-softening.

There are really only a few ways to be sure you don't overheat the brass. One is to use molten lead heated to about 700°F-750°F. You stick the case neck and shoulder into powdered graphite to prevent the lead soldering to it, and hold the head while you stick the neck and shoulder into the molten lead. You withdraw it when it gets uncomfortably hot to hold onto and immediately drop it in water or wipe it against a wet towel while rotating it. The cooling stops grain growth that weakens the brass.

Another is to use a cool flame. This is done the same way the lead is, but without the graphite dip. You use a candle flame and hold the case by the head and roll the neck and shoulder back and forth in the yellow flame until it gets uncomfortable to hang onto the head, at which point the water or wet towel wipe is used.

A third method is to use a hotter flame, like propane, for speed, but to use a temperature indicator on the case. Tempilaq or Tempilsticks are available for different temperatures. Hornady makes a kit that has you apply a dot of 475°F Tempilaq to the case below the shoulder so you limit how far the wall below the shoulder heats and it just assumes the neck has hit the necessary temperature by then. You can get the 650°F or 750°F lacquer and put directly on the neck. In either case, the indicator melts to clear when the temperature is hit, and you can expect some overshoot of the actual neck temperature past the melting point of the indicator. The faster you work the more overshoot, so the lower the indicator temperature you want to use.

If you can always work under the same lighting conditions, you can polish the brass in a tumbler, to get the color uniform, then use the temperature indicator until you can tell by the color of the oxide on the neck and shoulder when you are done. This is less precise, but a lot of folks use it. You just need the initial feedback about color to learn to tell.

Using an IR thermometer works in theory if you can set it to the emissivity of brass, but in practice you'd have to get the sensor awfully close to the neck to be sure the measurement area didn't overshoot the neck on either side and have the reading lowered by that. It would be tough to do without an actual IR camera with a threshold you can set, and I don't have 25 Large to drop on one of those.