Inside case neck lubrication

[nightwalker]

Unfortunately for me, I have always had a thing about making sure handloads are as "best" I can make them - I just cannot throw components in and pull the trigger!

Since I clean all my 6BR cases with an ultrasonic cleaner, I then find that when seating bullets I can get various amounts of seating resistance, arbor press, UNLESS I lightly lube the inside of case necks with graphite. (Runout is reduced when I lube)

This has got me thinking as to not knowing how much graphite is on the necks (eg some necks might have more on than others) - does this make a difference between rounds??

Any other suggestions as to how to lubricate inside necks or even ideas on this topic.

Does anybody run "000" steel wool to clean up inside case necks, what do others do?

 

[watercam]

What you are aiming for is minimum, consistent neck tension. Most bench resters and Long Range shooters I know use some type of neck-bushing die (usually without an expanding button) that gives .002-.003" smaller outside neck diameter than a loaded round for repeaters or .002-.001" tension for single loading. Many do clean with OOOO steel wool. The idea is to also eliminate as many variables as possible. You would be the first person I know who is trying to lube the inside of case necks. Doesn't mean no one else is, I just haven't run into it yet.

 

[Laurie]

I've also found ultrasonic or chemical cleaning can make cases 'too clean', or maybe it's caused by a residual film on the brass. Either way it seems to increase friction and/or give varying amounts of grip as seen in seating effort.

The other way of looking at the issue is to assume that the above doesn't apply, and a perfectly clean case tells you something about case-neck brass hardness or maybe other properties that inherently affect the case's behaviour. The only way I think you'd know for certain would be to mark any case that varies from the norm indelibly, then see if the same condition applies after the next firing / cleaning / resizing - if so junk the case or put it in the practice box.

Alternatively, simply ignore it all and stop worrying! Seriously, when I was loading large amounts of .223 Rem, I'd have batches of low number of firings Winchester, high number of firings ditto at the end of their lives, and new to newish Lapua Match in a single loading session. The high number of firings Winchester would often display really marked variations in the bullet seating pressure needed, noticeable on a large single-stage press. But, on the range, I couldn't see any deterioration in performance - on one notable occasion, ancient Winchester produced consistently smaller groups off the bench than near new Lapua with the same load, and I coudn't see any difference in velocity spreads either. This goes against everything I believe about brass quality and consistency, but there you are !!

After years of chemical, then ultrasonic cleaning of my brass, I now use Krazy Kloth on the outside and a brush on the inside. Lube on both sides of the neck is Imperial Sizing Wax, applied inside with an orange stick ('cotton bud' in US-speak?), and I've mostly moved to sizing with Redding Type S dies even with neck-turned cases. Cleaning the wax out of the inside of the neck with cotton buds after sizing leaves a very slight lube film - not enough to cause powder kernels to stick to the neck, but apparently enough to give very easy bullet seating. Even without any lube on the inside case neck walls but with the powder fouling given a hard brush for neck-only sizing with Wilson dies or similar, sees easier bullet seating than with completely clean brass - the residual carbon coating obviously acts as a lubricant.

Laurie,
York, England

 

[Posit]

I use neck bushing dies, and use mica inside the necks to lube during the seating process. Frankly, it has never occurred to me that lube might not be necessary... I use powdered mica to avoid any adherence of powder to the inside of the necks, and because its simple/easy. Since the amount of powder is minimal (I dip the necks into a bowl of mica) I don't see an issue with it affecting the finished cartridge.

I do use steel wool inside of case necks if they appear excessively dirty, but this is rare after cleaning with an ultrasonic cleaner.

That said, if there is any adverse effect in this process, I would be interested in hearing it... this is pretty much of a self developed process - always like to hear other views.

 

[fdshuster]

nightwalker: If you're getting varying degrees of resistance seating bullets, and only deburring your case mouths with the RCBS, Lyman type (looks like a rocket ship) de-burring tool, it could be caused by the sharp corner that is sometimes left inside the case mouth. Especially a problem when trying to seat flat base bullets. I prep all my cases using the K&M inside taper neck reamer that breaks that sharp edge with a nice smooth 11 degree entry angle, and all bullets seat smoothly with the same amount of seating pressure. I've never lubed the inside of my case necks prior to seating the bullets. I can take a flat base bullet and set it on the case mouth, rotate the case with the bullet pointing at the floor & it will not fall out. Try that after using the RCBS/Lyman tool only. Unless you are trimming the cases a lot, the taper reaming is a one time operation.

 

[Laurie]

If you're getting varying degrees of resistance seating bullets, and only deburring your case mouths with the RCBS, Lyman type (looks like a rocket ship) de-burring tool, it could be caused by the sharp corner that is sometimes left inside the case mouth. Especially a problem when trying to seat flat base bullets.

Good point Frank - I'd forgotten that issue. I bought the original 'VLD debur tool' many years ago - a long low-angle multi flute carbide model made by Hollands that only does the inside of the neck, and have used it since on everything and irrespective of the bullet shape being loaded. It does make a noticeable difference to bullet seating effort and consistency.

Laurie

 

[Fred Bohl]

From and older thread, see: http://www.accurateshooter.com/forum/index.php/topic,2939110.msg28367692.html#msg28367692

 

[fdshuster]

Laurie: Yes, I really like the K&M tool. The centering pin that goes thru the primer flash hole guarantees that the cut will be square, and even all around the circumference. The three pins that ride in the flutes control the cutting depth to the suggested 1/32". I'm so impressed with the tool, have one dedicated for each caliber.

 

[nightwalker]

Some very good comments, thankyou for taking the time to reply (Fred, your previous post/link was very interesting hadn't thought of dusting/dipping bullet base but think that might be more controllable than brushing inside neck?).

At the moment I use Imperial Dry Neck Lube, is this ok? would mica be better?

Do you think dry neck lube has any effect on barrel wear/cleaning?? Probably burns to nothing at powder combustion stage?

Cheers NW

 

[rain164845]

I don't know if this will help you, but I am using hBN to coat my bullets and I have noticed more consistent seating force. I too have wondered about the consistency of my coatings, but I am trying different things to see which works best.

Good luck,

Joe

 

[Fred Bohl]

Lynn,

I'll presume you mean a variance in the base to ogive (using a bullet comparator) measurement after seating. I normally see all within +/- 0.0005 of my target depth. However, while experimenting with the lubes and neck tension (neck ID interference) I did see a tendency for the bullet to move forward slightly with time for the first two hours after seating. This is not rigorous or a "statistically significant sample" but straight shank bullets moved about +0.0004 maximum and bullets with a pressure ring moved about +0.0012 maximum. So far this only appeared with neck tension less than 0.002 and with lube on bullets.

nightwalker,

My ongoing experiments have not yet achieved a level of consistency that I am comfortable with as to amount of lubricant on the bullet shank. So far the Redding Imperial Application Media with Imperial Dry Neck Lube (graphite) appears to give the most consistent "look" and "feel" during seating but I've not found any satisfactory means to objectively measure the results.

I've also tried the Neco Dry Neck Lube Kit (molybdenum disulphide), close to the same results but very difficult cleanup and RCBS neck lube (mica), least messy but not very consistent results.

 

[jb1000br]

Fred,

How are you measuring seating depth to the 0.0001"? BY your previous posts I know you must actually be measuring those digits if you are posting them. Interesting about the bullet being squeezed out after seating...

To the OP, with the ultrasonically cleaded brass I use NECO dry moly neck lube with the steel shot...works great, easy to deal with. Might be trying some Sentry Solutions stuff this year...

YMMV,
JB

 

[dreever]

Guy's
I use Imperial dry neck lube in this Sinclair product: http://www.sinclairintl.com/product/9136/s

Best thing I've found so far.

Danny

 

[lpreddick]

if neck tension is very slight and the friction between bullet and case neck is really slick, the compressed air can push the bullet out a bit. try this with an empty case with fired primer in place, polished inside neck and slick bullet with a snug fit. push the bullet in by hand and often the bullet will creep up until the compressed air leaks. this has to happen to some degree every time we seat a bullet. interesting.

if i can see you, i can touch you!BANG!

 

[Fred Bohl]

Jason Barney,

The way I measure seating depth of each and every round is by using a Redding instant indicator with land diameter bushing and dial indicator.

I chase the lands so I use a case and bullet specially prepared to be extended to "first contact". I then use that to set the zero point of of the indicator to allow offset either + or - enough to allow for the range of jam or jump desired. I then set the tabs of the indicator to bracket the desired jam or jump.

The simple dial indicator typically used has graduations at 0.001 intervals and can be interpolated to about 0.0002. For the testing of lubes I borrowed a Mitutoyo 543-392B Digimatic Indicator that has a resolution of 0.00005 and accuracy of 0.0001. It was also necessary to clean, and re-lube the instant indicator and develop a more careful/consistent stroke on the Sinclair Benchrest Press (#09-850 for the precision tests) handle to use that resolution. With this indicator, press and care, I'm confident of my results to about +/- 0.0001 but I would not want to use that level of equipment and care for every round of regular reloading as it required about 5 times longer than my usual quick check for each measurement.

 

[jb1000br]

Fred,

Kind of what I thought you might say...I love the Redding Instant Indicator...no 0.0001" res. here though Sounds like you have a good setup...definitely adds time to the process though.

JB

 

[GSSP]

Just loaded up 60 rds of 6.5x47 w/ 130 Berger VLD's yesterday for a tactical match I'm attending here in Utah tomorrow. Tried dipping both the neck and bullet into my little tin of Imperial Dry Neck Lube. Seating effort seemed definately easier.

Alan

 

[Fred Bohl]

JB,

Once you have an indicator with high enough resolution, two serious issues limit useful resolution. First fit/lube in the Instant indicator parts including using a lighter return spring than the Redding supplied one (fine for 0.0005 resolution). Second is the problem of the contact of the bushing with the bullet ogive - the standard spring and bushing tend to leave a skid mark on the bullet that limits measurement resolution but a lighter spring will leave a light ring and repeatable measurements.

lpreddick,

I've tried your proposed experiment to test your hypothesis about the compressed air in the case pushing the bullet back out. At least for my 6BR cases, the initial neck tension (interference fit) has to be less than 0.001 and the bullet has to be lubricated. Also in my trials, the push back was greater for loaded cases than empties - possibly due to higher percentage of compression of the available air for a given seating depth and thus larger increase in trapped air pressure. At 0.0015 or more neck tension (measured neck ID with pin gauges) all bullets stayed as seated.