Adopting XCB lube grooves for other boolit designs?

[Yodogsandman]

Any thoughts on adopting the XCB-type shallow lube grooves to other boolit designs like the Ranch Dog's?

I think the extra body diameter bulk of using the shallower lube grooves would increase the effectiveness of any boolit design for better HV performance.

[Maven]

Hasn't Lee Precision done this with "micro bands" on their tumble lube plain base and gas check designs?

[DR Owl Creek]

Hasn't Lee Precision done this with "micro bands" on their tumble lube plain base and gas check designs?

I think Yodog is asking about something more substantial than Lee's mini bands/grooves.

The NOE 311 188 (30 Hunter) from the group buy last year had a somewhat similar groove/driving band configuration, like the 30 XCB. Larry Gibson suggested this configuration too. It worked well on the 30 Hunter too.

Dave

[35 shooter]

It would also give the advantage of using tl type lubes or running through a sizer with regular lubes. Of course any boolit can be tumble lubed.

While the xcb boolits have other features designed in for high velocity other than the grooves, i can't help but feel many designs might benefit from the same bands and grooves as the xcb
has.
While most probably wouldn't reach the vel. potential of the xcb design because of nose design, taper, etc., a bit more vel. and accuracy potential might be possible over the deeper, wider grooves.
Very interesting idea and food for thought Yodog. I have the 35 xcb in hand now and have cast some with it and was wondering the same thing.

[Maven]

You mean something like this (See post #29) on a RD design? http://noebulletmolds.com/smf/index.php/topic,514.msg4044.html#msg4044

[Yodogsandman]

http://noebulletmolds.com/smf/index.php?action=dlattach;topic=514.0;attach=345;i mage (http://noebulletmolds.com/smf/index.php?action=dlattach;topic=514.0;attach=344;i mage)
http://noebulletmolds.com/smf/Themes/default/images/icons/clip.gif ELCO__1.05_GC__Mod-2F_166_gr_Sketch.Jpg (http://noebulletmolds.com/smf/index.php?action=dlattach;topic=514.0;attach=344) (84.29 kB, 800x600 - viewed 22 times.)

Maven, I thought I copied post #29 but, I guess to see it you have to click on the paper clip looking thing.

Well, this would be OK for 2000 FPS or so but, I'd like to open the envelope up a bit to say 2500-2600 FPS with a hunting profile boolit. The nose shape is just too long. I really like the RD's but, not the TL design. The ELCO lube grooves seem OK, though.

My interest now is in a 31 caliber, 180gr RD but, I can certainly see applications for skinny long boolits that tend to want to bend all over the place. A little extra thickness to the body can't hurt. Say, a 6.5mm Ranch Dog of about 150-160gr with XCB-type lube grooves.

[Maven]

Two questions, Yodog.... First, what does "XCB" refer to and second, what's the theory behind it? To put it another way, what are the advantages of the XCB concept?

[runfiverun]

speed and accuracy.
the XCB is for extreme cast boolit.
the case and such was designed to get to 26-2700 fps with a 165 gr 30 caliber boolit.
we have been pushing the 3,000 fps barrier with a few modifications.

[Yodogsandman]

Two questions, Yodog.... First, what does "XCB" refer to and second, what's the theory behind it? To put it another way, what are the advantages of the XCB concept?

Your first question is best answered by referring you to do a search for info on the "XCB" project. I'm a non-participant in the project, your question is much better answered by those that are directly involved and it has been discussed in great detail already in those threads.

As explained in post #1, I want to take advantage of just one aspect of the XCB's design. I didn't consider the ELCO lube grooves. I'd probably be able to get by with regular lube grooves on a 180gr RD but, where it doesn't exist in a 31 cal, and with the obvious strides being made with the XCB project, I thought that maybe one of the XCB boolits design features could be used with other designs to increase HV potential.

[1johnlb]

Yodogs,
I've wondered the same thing about if the xcb grooves would yield a higher velocities on some of the loveren designs. Maybe the xcb will change the cast boolit as we know it but that's yet to be seen. Your question is definitely valid but trying the right proven designs to see if they'll yield higher velocities or jacket velocities would be a possible game changer for the modern cast boolit, but then we still have the rpm threshold to deal with on typical modern barrels. But now thanks to the xcb team we know how to handle that.

[Maven]

Thanks for that explanation r5r!

Yodog...., I'll research the XCB Project shortly; and thanks!

[runfiverun]

umm yeah design a boolit properly.
the lube grooves are fairly far down the list, they do however affect the way air flows around the design in flight.
any anomaly on the surface creates waves of air [or create drag as it were] around the boolit at those sharp angles.
the angle at which this occurs can affect the boolit slowing down [buffeting] or wind affecting the boolit in flight more or less when hit from different angles.

a big reason for the design of the lube grooves was because we could get away with smaller ones since we can manipulate a lube to work where we need it to work in the barrel. [this only took 3 years of effort]
this allowed more bearing surface on the drive area of the boolit.
I actually wanted less lube grooves [1]

[runfiverun]

OH Maven about 3 threads down from this one is the 35 cal XCB design thread.
the 30 cal thread with the testing and such has been shut down for a bit until NO-1 can clean it up a titch.

[Yodogsandman]

There's some good discussion of the XCB boolits design here today, posts 288,289,290,291...

http://castboolits.gunloads.com/showthread.php?268811-SLOW-Twists-and-FAST-Casts-Using-CUSTOM-Barrels-Results-Please/page15

[Maven]

Yodog...., I read all of the posts on the XCB design last night. It's compelling enough that I'll give serious consideration to one of NOE's .30cal. molds. Thanks for the suggested reading!

[TXGunNut]

I think the extra body diameter bulk of using the shallower lube grooves would increase the effectiveness of any boolit design for better HV performance. -Yodogsandman

Interesting thesis, my friend. It seems R5R has the Readers' Digest answer in post 12 but will have to research that more when the earlier XCB tread comes back. For my purposes I feel the TL design is underrated. Seems everything I had for awhile was BP or TL type lube grooves, nothing in between. Until I wanted to go a little faster to utilize the case capacity of the 35 Whelen I didn't need anything else. Your thoughts about the 6.5 seem valid as well.
Interesting thread. I've been thinking about how lube groove design affects boolit performance too but my only conclusions are that most of my conventional design boolits carry more than enough lube (I generally fill two) and secondly I don't have a clue about how lube grooves affect boolit flight.

[Yodogsandman]

TX, The 30XCB thread has been back since at least the 18th.

The tumble lube design certainly accomplishes the extra body bulk for extra resistance to bending or riveting. I just never liked the idea of only being able to use a liquid lube, though. Most, if not all liquid lubes use alox, which is suspected to cause lube purge flyers. The use of XCB type grooves allow the use of any lube you want and the lube can be tailored to your load (with or without alox).

I never considered air flow around the boolit in flight. I suppose the XCB type would allow a better flow than the turbulence caused by the TL micro bands.

[popper]

All the mould designs I have modified have a single 016d x 040w wide groove. I ESPC them and chronyd one (170gr) at 2789, 308W. Accuracy was 2 1" groups and one 1"x3", I wasn't shooting for groups, just fps @ 50 off the bipod. 31-200G-D has 2 grooves, 028d x 060w. IMHO, TL grooves are too many, too close together. My 'grease' lube is veggie oil, have not seen any difference in accuracy - it all purges off in a fine mist.

[Yodogsandman]

What about a 35 RD XCB? Maybe about 280gr? What a thumper that would be!

[runfiverun]

yodog.
you have to design a boolit with a plan in mind.
if you are after straight line speed like a dragster you run a specific spring package for front to back weight transfer.

if you are building a GT car you need a side to side balance with heavier front springs to handle the braking loads transfer so variable rate springs are needed.

boolits work the same way.
you have to balance performance on target with how you launch them.

[Yodogsandman]

R5R, Thanks for the analogies! I understand them but, I'm not really a car guy. I'm not a boolit designer either. Just an idea that could be good or bad, that I thought needed discussion. I certainly appreciate yours and others input on the subject. The Ranch Dog designs have done pretty good for me. The 30 XCB is doing great with those participants. The only part of the XCB that could possibly be adopted is the lube grooves, in my estimation. Further I understand that the XCB is a system that encompasses a lot of solid accuracy ideas that are known to work. I'll leave all the actual designing to the wizards. You know, it's all an educated guess...

That is until someone designs one, makes a boolit mold and tries it. Oldblinddog has done just this with Tom at Accurate Molds and hopefully can tell us some day if it works.

http://castboolits.gunloads.com/showthread.php?281998-Ranch-Dog-XCB

[oldblinddog]

I received an email from Tom saying my mold is ready to ship. Will report on it as soon as I can but I won't be home again until about the 25th of this month. Then we will see if this idea works out.

[runfiverun]

I have seen that boolit.
http://www.accuratemolds.com/bullet_detail.php?bullet=31-165A-D.png

compare it with this one.
'somebody' drew up earlier and has taken over 2400 fps in a 10 twist barrel with no drama and groups below 1/2".
if you remove the holes In the 200 and replace it with metal [which helps grab the rifling] you get this one.

[Yodogsandman]

Looks like a 165 RCBS silhouette clone to me.

[runfiverun]

not even close.
.001's here and there and sloping degrees make all the difference between good [1/2"] at 1900 fps and good at 2400+ fps.
the rcbs silh won't hardly break 1900 and hold accuracy.

[Yodogsandman]

So, looks like we should be giving credit and thanking the "somebody" design wizard, too. Along with the Ranch Dog designer and the whole XCB design team. Thanks for pointing that out, R5R. I wouldn't have had a clue.

I'm thinking now that toes have been stepped on here and that was not in any way my intension. I apologize if this thread has ruffled anyone's feathers.

[oldblinddog]

if you remove the holes In the 200 and replace it with metal [which helps grab the rifling] you get this one.

when you say "the 200" to what are you referring? I'm not following you.

[oldblinddog]

I'm thinking now that toes have been stepped on here

How? Anyone can do whatever they think is a good idea. Approval is not required.

[MBTcustom]

How? Anyone can do whatever they think is a good idea. Approval is not required.
True.
This is the internet, and anything can be said by anyone, and you really cant get too bent out of shape about it, because the facts are the facts.
For instance: there was no XCB "design team". I designed the XCB bullets, rifles, and equipment myself.

I called run5run when I was getting close to having a workable print and asked: in your opinion, what are the most important design elements of an excellent cast bullet. R5R recommended that I should fit the angle of the ogive to the throat precisely which I was already doing (for the record, the XCB has been so effective in so many rifles with so many throat configurations, I now believe this to be irrelevant.)

Next I called Larry Gibson and asked him the exact same question: In your opinion, what are the most important design elements of an excellent cast lead bullet?
It was he that recommended the shallow lube grooves, and I have to give kudos to Larry Gibson for that, because it was something that I was not thinking of, and I would never have done. (it bears mentioning that both the 30 and the 35 XCB cartridges have their roots in concept cartridges that Larry Gibson proposed years ago.)

Later, I also got input from Al Nelson at NOE bullets concerning ogive shape and worked with him to find a shape that I deemed suitable, and he deemed able to be made in the first place.


When dealing with an online forum, There's always going to be people who try to take credit for someone else's work, and there will always be infighting, and internet garbage.
However, what keeps the place running is results and people that are here to give and not to take. The XCB research team (comprised of myself, Bjornb, Larry Gibson, and sgt.mike) has given you the XCB project results. It's all right there, and the targets and snapshots of the range sessions spanning several years demonstrate a truth about HV shooting that cannot be denied.
As long as real information gets posted in the middle of the fuzz, that's all I care about.

Now, concerning adopting XCB lube grooves to other designs, I do think it's about time to change our thinking in this regard. You look back on the old BP designs and the lube grooves they had at the time and compare to what we have here today, there is really very little difference. Yet we have some of the best lube ever these days, and I've been shocked at what is being done with WLL 2500+, 2700+, BAC, and 45-45-10. Everything points to the same thing: We really don't need as much!
Also, it seems to me that making the grooves deeper and wider robs structural fortitude from the bullet, creates stress risers and weaknesses, robs bearing surface, and sprays lube all over your chronograph and target etc etc etc.
To tell you the truth, I have a lot of respect for the original Ranch Dog designs with the tumble lube grooves, and I am using them with standard lube on a regular basis now. It works just fine! In fact, you don't even have to fill all of them to get good results! That certainly seems to point to the possibility that we are just horribly over lubing our bullets.
I don't think you're going to see a huge difference in performance with the XCB style lube grooves (unless you really start pushing the envelope for accuracy and/or speed) but it just seems like a better design strategy. At this point, I look at standard deep lube grooves like fin fenders and whitewall tires on a car. They don't hurt anything, but you're not going to see them at Daytona either. LOL!

[Yodogsandman]

Goodsteel, Thank you for doing all this and clearly explaining the process you used. I surely appreciate the work of all the wizards involved in the project.

I've explained that I'm not a car guy but, from what I understand, improvements made on race cars at the track are adopted to production vehicles for everyday use.

[MBTcustom]

Thank you YDS. But there's no wizardry here. Read my signature line.

There is no such thing as magic. Magic is just good science, badly explained. - my father.

It is my desire that people will adopt the XCB method of careful documentation and scientific method to reach their own goals, understanding that the XCB project is just my best shot at cutting to the chase and doing it right.
There were lots of assumptions that I made at the beginning that were wrong, and that has been exposed throughout the project. Like matching the angle of the ogive precisely to the lead for example. It's important to have an angle there, and certain angles work better than others, but it doesn't have to match a particular rifle exactly. When we started this, I thought it did.
Another example is thinking that I needed Linotype alloy to shoot really high velocity. Turns out, if everything else is correct, you can get to 2700FPS with COWW sweetened with tin, and in that range, it actually shoots better in my rifle, but trades places with linotype at 2700+ FPS. Interesting!

[oldblinddog]

True.
This is the internet, and anything can be said by anyone, and you really cant get too bent out of shape about it, because the facts are the facts.

Absolutely correct!



When dealing with an online forum, There's always going to be people who try to take credit for someone else's work, and there will always be infighting, and internet garbage.

I have been an avid reader of everything posted on the XCB and Ranch Dog boolit(s). I think that it has constituted a tremendous effort by all involved and I appreciate their work. What I have not been able to understand is the tiresome bickering that has been a part of every thread on the subject that has required the intervention of moderators. It is just baffling to me that anyone is compelled to interject negativity into a conversation. I, for one, was raised with the admonition that if you have nothing nice to say then you should say nothing at all. Having been trained as a scientist, I applaud the research and the willingness for that research to be peer tested. Anyone is free to purchase a mold and conduct their own tests, with their rifle/cartridge/alloy/load combination and then post the results.




Now, concerning adopting XCB lube grooves to other designs, I do think it's about time to change our thinking in this regard.

Without the work done by others I would not have been able to (very simply) combine the Ranch Dog type nose with the lube grooves of the XCB. I am taking no credit for doing what seems merely obvious to me. If it works well it will be posted in the thread I started. But, if it is a failure, it will also be posted.

Steve

[MBTcustom]

Without the work done by others I would not have been able to (very simply) combine the Ranch Dog type nose with the lube grooves of the XCB. I am taking no credit for doing what seems merely obvious to me. If it works well it will be posted in the thread I started. But, if it is a failure, it will also be posted.Steve

Steve, please do so by all means! If I had wanted to get rich on the XCB concept, I would have patented it and posted only the results while keeping the juicy details to myself.
It is far more important to me that the cast bullet community have the knowledge of how to shoot blazing fast, startlingly consistent, or shockingly accurate cast bullets at their fingertips. Furthermore, as I mentioned, I feel that we have just scratched the surface of shooting HV. My goal was not to find out every nitty gritty detail and method for how to do this, but rather to provide you and others with a foundation by which to develop your own methods, as well as an admonition to "keep it real" with ten shot groups, and direct chronograph readings and range measurements.
The XCB project is a starting point, and every single conclusion was staked in place with careful measurements, and mudded in with real life groups on paper. We are still learning, and the lube groove design was just one piece of the puzzle, but there is much more out there to learn and discover.
The danger is to make conclusions based on insufficient or badly collected data. Like if you set up a chronograph and carefully record your load data, but then you go shoot at rocks on the berm and conclude you have a 2MOA group because the 2" diameter-ish rocks moved every time, it all comes crumbling down and the data means nothing.
If I have accomplished nothing else, I hope that I managed to convey the importance of keeping it real and always being on the lookout for false positives etc etc etc.

It thrills me to no end that you are doing the same and are running an experiment along the same lines! We need more of that here at castboolits! There is no end of stories of what can be done when all the planets align just right, and I enjoy those very very much, and I can tell you a few things that I have done that would blow your mind, but what we need to make those "once in a lifetime" occurrences more frequent is a better understanding of what happens without fail every time.
Kudos to you, and to anyone who is curious enough about something to put it to the test with gunpowder.
Let me know if I can be of any sort of assistance, and carry on sir!

[oldblinddog]

Thanks Tim, I appreciate that.

[TXGunNut]

yodog.
you have to design a boolit with a plan in mind.
if you are after straight line speed like a dragster you run a specific spring package for front to back weight transfer.

if you are building a GT car you need a side to side balance with heavier front springs to handle the braking loads transfer so variable rate springs are needed.

boolits work the same way.
you have to balance performance on target with how you launch them.

I think you lost me a bit on this one. I know a little about racing but I'm not sure how the dragster vs circle track/road course analogy works here. The circle track/road course suspension system is quite dynamic and in many cases a good substitute for horsepower. A dragster suspension is all about keeping all four wheels on the ground, power to the rear wheels (and hopefully pavement) and pointed in the same direction. As you know I'm just learning to appreciate boolit design, I'm generally happy with a hunting boolit with rather pedestrian velocities but going fast is fun and educational.

[runfiverun]

like Tim pointed out in a post up above he has noticed certain dynamic changes based on the alloy he has used.
a fluid movement of the alloy during some points of pressure rise will tend to shoot smaller groups with a softer alloy if the design of the angles allow the transition of the softer alloy to happen smoothly.
you have to consider the points of pressure applied by the powder and the spikes the boolit itself can apply to the pressure rise of the powder.
it becomes a fluid dynamic flowing system where the boolits shape will actually change somewhat during the transition from case to muzzle.

for a dazzling high speed burst where a harder alloy resists deformation as much as possible the transition of the boolit into the barrel comes under a different set of pressure variables, because it can be transitioned by a faster powder.
the distance of the angles on the nose from the barrels steel can still influence the powders transition to full pressure but it generally is done later in the pressure rise so doesn't show on trace equipment quite as pronounced.

if you consider the powders speed and the transition period of the boolit in the pressure rise time frame you'll see how the alloy can influence the powder and the powder choice will of course affect the alloy choice.
using the same alloy for different cartridges, boolit design, or powder selection is not going to give optimum results.
when you consider high speed, high accuracy boolit designs and powder selection your alloy is going to be a [the one] fluid changing thing within the system, and you have to think of how each part of the cartridge influences and is influenced by the other part of the package.

blind dog:
I was referring to the accurate 200gr versus the 165gr designs.
nothing directed towards you, just a note of the similarity's and differences in the 2 designs.

[oldblinddog]

blind dog:
I was referring to the accurate 200gr versus the 165gr designs.
nothing directed towards you, just a note of the similarity's and differences in the 2 designs.

i didn't think it was directed at me in particular. A link to the 200 gr would have been helpful. Can you provide it? I prefer not to guess which you are speaking of.

Thanks,

Steve

[GabbyM]

Any thoughts on adopting the XCB-type shallow lube grooves to other boolit designs like the Ranch Dog's?

I think the extra body diameter bulk of using the shallower lube grooves would increase the effectiveness of any boolit design for better HV performance.

http://castboolits.gunloads.com/attachment.php?attachmentid=134641&d=1426964408

I made the lube groves on this bullet more shallow than the Lyman 311284 round nose that inspired it Also did away with top scrapper grove. Groves went from .2766” to .2920”.
This 31-220-LG was not designed to follow the work of the XTB project. Shallow lube groves were suggested to me here on the forum and it seamed a good idea for speed plus terminal integrity. Bullet design is for a heavy hitting and deep penetrating hunter in the 30-06. Last six months I’ve only worked and not played so it’s untested. Will be using an alloy with Copper at between .3% to 1.0%. Probably start with around 40,000 psi under it from slow rifle powder then see what happens. 30-40 Krag speeds would tickle me. I wanted a bullet with the flat nose of the RCBS 30-180-FN plus more weight.

[TXGunNut]

if you consider the powders speed and the transition period of the boolit in the pressure rise time frame you'll see how the alloy can influence the powder and the powder choice will of course affect the alloy choice.-Runfiverun

Thanks, seems I'm doing it backwards. I'm using only a few different alloys and hardening strategies and trying to match the powder to the cartridge, alloy and velocity. (Re-)Read Fryxell's "Lubricating Cast Bullets" article last night and this lube groove thing is starting to make more sense now. IIRC Uncle Elmer thought of lube grooves as pumps and that analogy is making more sense to me now. There's a heck of a lot of things happening between the time the primer starts the party and the moment the boolit clears the crown. J-words suddenly seem somewhat low-tech by comparison.

[oldblinddog]

Any load starts with the projectile, i.e. what do you want to do? The alloy will be part of that equation, so I don't think you are doing it backward. Boolit design, alloy (should be a known alloy), lube, powder, load. Don't you think?

Grooves are both reservoir and pump.

[TXGunNut]

I'm re-thinking a lot of things lately, oldblinddog. And you're right, alloy is important to me since I'm a hunter and I feel a properly alloyed boolit is the key to a good hunting load. One upcoming project is going to require some serious thinking about alloys. Threads like this one help me realize how much more I have to learn. Been doing a lot of reading and had a very enlightening PM exchange with R5R a few days back and I'm still mulling over and researching some of the things he told me. Some of the folks around here amaze me with the depth of their knowledge.

[oldblinddog]

Some of the folks around here amaze me with the depth of their knowledge.

Me too! Also, everytime I get to thinking I know most everything, my wife reminds me that I have CRS.