I cant for the life of me figure out why I have so much inconsistency in neck tension with this brass. This is 2 times fired brass in the same chamber (howa), annealead with an AMP, then sized through a forster full length sizer with 262 ball. All necks brushed with graphite and bodies lubed with die wax before sizing. I see the inconsistency with my mandrel checker, and in the arm of the arbor press while seating. What is changing so much that I cant see, that is affecting this neck tension?
Neck Tension Inconsistencies on Lapua 6.5CM Brass
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Maybe ditch that expander ball and get a ball with a better design? Or better yet, ditch the expander ball all together and expand the neck with a seperate operation with an expander mandrel??? I find the latter to produce much more consistent results.
I’d wet tumble the brass to get the zinc oxide off the necks, and use a .263” mandrel because .262” is just too small. A lot of people think they’re setting .002” neck tension with a .262” mandrel but it’s actually more like .003” due to brass springback. I have found that .001” is better actually when you’re dealing with a long bullet seated deep.
Brushing the annealing oxide residue is a big help.
Mandrel instead of ball gives more consistent results over the entire length of the neck as well with all the addition surface area to act upon the necks for a longer amount of time.
You trimmed and chamfered? Make sure you don’t have a sharp flat cut edge that’s scraping bullet jacket. Chamfer it to a bevel.
Mandrel instead of ball gives more consistent results over the entire length of the neck as well with all the addition surface area to act upon the necks for a longer amount of time.
You trimmed and chamfered? Make sure you don’t have a sharp flat cut edge that’s scraping bullet jacket. Chamfer it to a bevel.
That layer created by annealing is exactly why I mentioned not using a dry lube on the neck. Even amp recommends against graphite, it don’t work well and can result in excessive force being needed and galling.
That combined with using a standard die that is likely squeezing the piss out of your necks is resulting in what you are seeing. I had the same issues when I started annealing, because I used graphite on the necks. Had to adjust my process and everything else started getting more consistent.
That combined with using a standard die that is likely squeezing the piss out of your necks is resulting in what you are seeing. I had the same issues when I started annealing, because I used graphite on the necks. Had to adjust my process and everything else started getting more consistent.
Isolate the problem; start with sizing a few and measuring the outside of the necks. Also, change only 1 thing at a time to find the problem
Questions:
- Do you have a force gauge on your arbor, or are you just doing by feel?
- What is your brass cleaning process? Wet tumble? Pins/no pins? No cleaning? Dry tumble? Ultrasonic?
- How are you brushing in graphite? Have you tried the application media?
- When you say "mandrel checker", what are you referring to? Are you using pin gauges or something similar to test neck ID?
Below is an overlay of a couple groups of rounds that I did a few weeks ago. The blue is 45 rounds - 43 of which fall within 8 lbs. I tend to mark the "fliers" to use as foulers. It's taken a lot of playing around with different things to get the forces this tight.
Anyone care to guess what the orange plot is? Hint: it ain't what you will think and may surprise you. It took some emails with AMP to figure it out.
Yeah, what AMP says....that I could find...is their view is that graphite doesn't stick well to necks after they've been freshly annealed. Dunno if this is real or Memorex? I don't brush out the necks after annealing but perhaps I should start doing so.
For sizing, I do use a mandrel and I spray the cases with Hornady One Shot and it seems to work fine. I also put a bit of Imperial Sizing Wax on the mandrel (hey, I wear belts and suspenders too! haha).
For bullet seating, I've used graphite and I've never noticed it having an issue sticking to the inside of the necks but I may just not have paid sufficient attention. I've also started using Neo Lube #2 that @Rocketmandb brought to our attention in a thread. Now that I can def tell is sticking to the inside of the necks. He dips....i tried it...and frankly I found applying with a q-tip to work just as well and not as messy.
@Rocketmandb - please refresh my memory (at the risk of hijacking this thread)....did you see a objective difference in seating force and downrange performance between dipping and q-tipping Neo Lube?
It depends on how you apply it. Redding’s black jar thingy holds too much ceramic media. If you try to shake it there is not enough movement of the media to distribute the graphite from the bottom of the jar to the top. I dump half of the media out and that allows everything in the jar to mix well when shaken. Shake it till the media is black, not grey, black. Problem #1 solved.
Problem #2, getting the graphite to stick, is remedied by technique. A lot of people stick the case neck in the media, then turn and lift. That’s not going to get a sufficient amount of graphite to stick. I dunk the neck into the media rapidly back and forth about 12 times. I hold 3 cases in my fingers at once. Believe me, plenty of graphite will adhere to the neck, annealed or not.
I agree that a clean neck, free of zinc oxide, will attract the graphite better than an annealed neck. I think it’s good to remove the oxide. US cleaning in vinegar will do it. So will stainless tumbling. Neolube is good. Also, you can run a qtip soaked in carb cleaner down the neck. It will evaporate and leave a very thin film that attracts graphite. Or you can skip the graphite and try seating bullets as the film does lube the neck somewhat. I haven’t contaminated powder that way, but I dunno about long term storage.
Tried it, and for some reason, while seating, the neck just scrapes the wax right off and it's like I never waxed them. The grahite is like anti seize; that shit penetrates and stays put.
Neck tension with Alpha brass is a whole 'nother story lol. To get any decent sort of tension, i have to not use ANY expander ball lol. I like a little tension for several reasons but that's a whole other thread right there. If using a 263 ball on this brass, it would be almost like a hotdog down a hallway.
I’m speaking by to the sizing. Not bullet seating. I don’t lube my bullets though I have tried graphite when I was having the same issues.
Iv used graphite. Still have a boat load of it I never use. It’s not as effective as a wet or wax lube ime. I lube everything with wax, size/mandrel. Dry tumble it all off and seating forces have been very consistent.
On an annealed neck, you can feel the grittiness. Even alpha has finally come out and reccomended a tumble to knock down the friction. Same can be said for the other premium brass.
Iv played the graphite game. Glad to not need to use that messy stuff anymore.
What annealing oxide is there? And is this on top of the baked on carbon? Can I remove the oxide without removing the carbon?
No necks are trimmed but everything is chamfered. I will try an expander mandrel next. I just hate having to do two separate functions due to time. Though, how did the benchresters do it before sizing mandrels?
Graphite CAUSES galling? Not sure how the Australians do it, but if you dont use graphite on these necks, your seating pressure will be so hard, the seating stem will hammer the SHIT out of these jackets. (i dont do the whole one thousandths of neck tension like most people do. I feed from mags, and i dont want any bullets getting jammed back because I ran my bolt too fast)
My Forster dies are indeed standard, but either they really dont squeeze the shit out of my brass, or my brass has TREMENDOUS springback, because I just loaded two loads, with no expander ball whatsoever, and with graphite, they felt really nice and smooth, with not a ton of tension.
Good questions here. I did have an arbor press with a gauge on it, but it fell off my bench and I havent had it in for service yet. I use this little K&M press. It has a really short arm so less torque; it is more sensitive so to speak. Lets me feel precisely what's going on during the seating.
Brass cleaning? I dont. My brass stays pretty clean on my bolt rifles.
I brush my graphite in by 'soaking' then dusting off a 223 bore mop and swabing the necks with it.
My mandrel checker is very similar to forsters neck tension gage. I can gage consistency between each case neck.
A simple lube change in your sizing operation is likely the simplest and cheapest option to try. As I said I lube my case with a wet lube, imperial wax mostly and run my finger over the rim so the mandrel/ball catches some lube.
I have played the graphite game. I know I’m wrong according to everyone but I’d give it a try. It worked for me.
Virgin brass is a whole nother story. And I can go even deeper on that on doing something with a decent lube and tumbling to remove the friction from the neck.
I still haven't done a good side-by-side test. I'll do so next batch of ammo.
I’ll be honest, I don’t use a force gauge or an arbor press. While feel is not an exact science, I do believe the target and numbers from the chrono.
The process I use with Lapua brass is to AMP anneal, clean the outside of the case neck with steel wool and wipe the entire case clean. I size with Imperial Sizing Wax using neck bushing dies without expander balls. I brush the inside of the necks using a nylon brush on a prep machine and lube the inside of the necks by dipping in Imperial Dry Lube, drop powder in and seat bullets. Pressures when seating feel the same across the lot I’m loading. My SD numbers across the many rifles I load for range from a low of 3.2 fps (6 Dasher) to 8.7 fps (.223) on the high; most fall between 5 and 6 including 6.5 Lapuas and 300 Normas.
I do have a 33XC that uses an expander ball where I use a Q-Tip to apply a light film of wax inside the neck before sizing and then remove the wax with alcohol before dipping into dry lube. SD numbers on this rifle are 6.8.
This process has worked for me for many years. Best of luck finding a process that gives you the results you’re looking for.
The process I use with Lapua brass is to AMP anneal, clean the outside of the case neck with steel wool and wipe the entire case clean. I size with Imperial Sizing Wax using neck bushing dies without expander balls. I brush the inside of the necks using a nylon brush on a prep machine and lube the inside of the necks by dipping in Imperial Dry Lube, drop powder in and seat bullets. Pressures when seating feel the same across the lot I’m loading. My SD numbers across the many rifles I load for range from a low of 3.2 fps (6 Dasher) to 8.7 fps (.223) on the high; most fall between 5 and 6 including 6.5 Lapuas and 300 Normas.
I do have a 33XC that uses an expander ball where I use a Q-Tip to apply a light film of wax inside the neck before sizing and then remove the wax with alcohol before dipping into dry lube. SD numbers on this rifle are 6.8.
This process has worked for me for many years. Best of luck finding a process that gives you the results you’re looking for.
No; totally factory. I know, super odd. Either that or this specific combo of berger and alpha combined produces a lot of surface lubricity (which alpha told me it didnt) or this graphite is some SUPER shit and I should add it to my engine oil to free up 10hp lol.
I tried the exact same method, which is to wipe a little wax on the case mouth so the bullet would catch it and use it and nothing; Still felt hard and gritty. This graphite really does slick things up TREMENDOUSLY, but it doesnt change the seating feel. I can feel it. One drops in really nice and smooth all the way down, while another is hard and not smooth. Kind of like slipping in then resisting, then slipping a little, all the way though the seating operation. I should get another arbor press with gage to replace the one I had. Then I could at least post some numbers.
This annealing thing has me thinking. I'm going to try brushing the necks to get rid of that stuff you guys are talking about, and load a ladder. Though I just though about that mandrel option; on these last two loads I used, I didnt even use an expander ball... That's what confuse me. Unless the neck thickness varies widely which I doubt, then the only other two things that could vary between pieces would be springback rates, or the uneven application of that oxide layer from annealing...
Speaking of engine oil. . .
Back in the mid '70's when I had been working in the aircraft industry, a bunch of synthetic oils for auto's came out (synthetics was normal for aircraft and I always wondered why not for autos). One of the oils that came out touted how effective their additive was for reducing friction. The additive was graphite. Not long after this synthetic oil with graphite additive was out, many reports of engine damage started coming in. The additive was causing excessive camshaft wear. Apparently, the high pressure on the camshaft lobes didn't like graphite in the oil. The company went out of business in a short time and no other oils used any graphite as a super duper additive.
I've been using Mobile 1 ever since and go 20,000 to 25,000 miles between oil changes (my 20 year old SUV I bought new now has over 210,00 miles and still running like a well oiled sewing machine).
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The forces you're feeling on seating come from three things:
1) The amount of material being expanded combined with the ability of that material to resist expansion (spring back).
2) The coefficient of friction between the bullet surface and the neck surface.
3) The bearing surface area - this obviously grows as you seat, at least until the beginning of the boat tail clears the neck, at which point it remains constant.
So, here's where you can get some issues:
1) You've got inconsistent spring back:
a) Due to inconsistent neck thickness, which causes differing amounts of spring back
b) Due to amount of material expanded due to inconsistent inside neck diameter
c) Due to inconsistent inside neck diameter due to too much carbon build up in the neck (unlikely)
2) You've got inconsistent friction:
a) Due to varying amounts of carbon from one neck to another
b) Due to different surface conditions from one neck to another
c) Due to inconsistent application of graphite - which could be exacerbated by annealing
d) Due to varying surface conditions of the bullet (e.g. you pulled a bunch and they get marred)
3) You've got inconsistent bearing surface:
a) Due to varying length of the flat area of bullets - see previous post and the orange plot
b) Due to varying neck length
I'm sure I missed a few things, but these are where I'd start to try and narrow down what's causing the issue. And get the force gauge fixed. Getting decent data is key here - it might be (probably is) a few of these things, and simply guessing at how much each one helps is just going to cause frustration.
It works for me too, though I use NeoLube #2 now instead. I think I narrowed down the reason why it works for me to the fact that I use an ultrasonic and I don't thoroughly rinse - just a light rinse on each case after removing from the ultrasonic. This leaves a small amount of residue that I believe enables the graphite to stick better to the case necks.
I think what we are doing to clean the brass can be as big of a factor as the lube as well, and worth mentioning.
I’m dry tumbling only with lyman polishing media, my media definetly leaves a slight residue in the neck.
Iv always seated on an arbor press, and have been chasing consistency for a while, especially with virgin brass.
In my experience mixing One Shot and any other lube is a bad idea, so if you are spraying with One Shot I would not put wax on the mandrel. If you want to lube the mandrel try hitting it with a quick spray of One Shot.
Inconsistent carbon sounds like a good source too. Though I hear from a lot of sources never wet tumble fired brass as it removes that carbon from the neck, and you want that carbon. Is that not correct?
I've been wet tumbling fired brass pretty much my whole life. Never been a problem. I use stainless steel ball bearings instead of pins because they don't get stuck in the case mouths like the pins have a habit of doing and I can always tell if there are any inside a case. I've yet to have a ball bearing left inside a case if I run them through the media separator, but if its a small batch, I sometimes just rinse them and dump them by hand.
I would have guessed it's "what you think" (either annealing or Neolube vs dry lube) so I won't guess, but I want to know! What did you figure out?
The first 45 bullets were out of one box of lot #1468 of Berger 220s. Then I ran out of bullets and had to open a new box of lot #1468 of Berger 220s. Nothing else changed. Same brass prep, same press setup, same time, same everything. Literally, all I did was get up, walk over to where all my bullets are, retrieve a new box of the same lot, and continued seating.
I contacted AMP to get their perspective and the first thing they said was, "measure the bullets."
Unfortunately, I had taken those last 45 bullets out to the hills the weekend before. Fortunately, if you want to call it that, one of those rounds had a bad primer. So, I pulled that one bullet and compared it to a few bullets out of the new box.
What I found:
- The OAL was essentially the same.
- The body of the bullet was ~.025" longer on the new-box bullets - measured by putting a comparator on both ends of the bullets.
Looking at the graph, you can see that the new-box bullets engaged around .025" earlier. That makes sense if the body is longer. You can also see that the slopes of the graphs are essentially the same. The reason the terminal forces on those bullets is higher is that there is more bearing area. In fact, if you just slid the orange plots to the right, they would match up.
EDIT: Morale of the story, measure your bullets every time you open a new box.
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Apparently, when you refer to the "body of the bullet" you're referring the the Bearing Surface.
Several years ago now, I discovered this difference in bearing surfaces between lots with two different lots of 168 SMK's where there was a difference of .033". So I sorted through them and set aside 20 that were .033" longer than 20 of the shorter. Loaded all 40 up and shot them into 10 round groups and chronoed all the shots. As I thought there might be, the .033" longer bearing surface rounds had a very different average velocity and a very noticeable difference in POI at only 100 yds.
Like you, I discovered it's a good idea to sample measurement for every new lot/box of bullets as there can be significant differences. But I'll point out too that the difference in bearing surface length being quite small, like .010" or less, isn't really going to show up on target or in velocity due to all the other noise that's going on.
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I agree with this - you'll get natural variances bullet to bullet no matter what. I certainly have been wary of different lots of bullets, but I have to say that I was surprised at the .025" difference within the same lot.
Actually, I've seen that happen within the same lot too, but that much is pretty rare. It makes me think a few leftovers from one lot is mixed with a new lot???
Those neck mouths sure look peened.
So, it still looks that way after trimming? I wouldn't think it'd still look like that after running them through you Henderson with a 3 way cutting head???
I think that is just the lighting. They are perfectly smooth.Those neck mouths sure look peened.
