Paul H... I would make the best candidate because I am probably the smallest... you want the video to be funny, right?

I handle recoil better then most... but shooting stances become prohibitive.

Hi Rob, would it be your opinion that the K&P clamshell brake is the most effective brake for 50 caliber and above? Would you rank George's New design as being the second most effective brake?

Mr. Clean, PaulH , DD- Yes Paul is right we have had a rash of Loser Trolls on this Forum who reinvent themselves nearly daily. It'd hard to distinguish sincere criticism from Troll-Talk . We are especially wary of new folks. As for the brake, unfortunately no one makes a clamshell with a cone that will pass a .625 bullet. Clamshells have the advantage that the recoil gasses are directed backwards and will literally pull the gun off your shoulder. I would use one in a second if I could get one. I really don't want to build a welded up version or one screwed together. George and I talked at length about this and he states that he thinks these brakes are near clamshells in efficiency. I doubt it frankly, but I fired another 600 with and without this brake and the difference was dramatic. It seriously works. Is it as good as a clamshell? Again probably not. One good thing though is that all the dimensions work perfectly for the 600 OK.
PaulH- Sure let's start a raffel for a Buff hunt with the 600 OK. Paul Zorn from Zimbabwe is coming to visit me next week and maybe we can talk him into a hunt?-Rob

I am most definatly not a "trash troll". I take the hobby,sport or whatever you may wish to call it,of shooting very serious,but there is always time to joke and play around. I like big guns,the bigger the bullet,the more powder hopefully more fun! All joking to the side,the 600 OK is a neat idea,I hope it works out,and is not to brutal If given the chance I would most definatley be at the front of the volunteer line to test fire this beast Happy shooting

Robgunbuilder!

What velocity do you think is possible with a 750 grain A-square dead tough or a 750 grain lion load in the .600 Overkill????

Thanks!

I thought I'd try posting a few pictures of the 600 OK brass being turned and a comparison of a few different loaded bullets. FWIW
John







600OK - 416 rem - 7mm STW - 338 win



600OK with 900gr round nose solid

Hope to hell this works

[ 01-26-2003, 08:58: Message edited by: fritz454 ]

Frits!

What bullet is it in the .600 Overkill in the first picture where it stand with the .416, 7 mm STW and the .338 win???

Robgunbuilder! What velocity do you think is MAX for a 750 grain A-square bullet in the .600 Overkil I think the .600 OK will beat the .577 Tyrannosaur in energy with a 750 grainer.?

Overkill,

That is one of the go /nogo gages I made for Rob. It is solid brass but the nose shape is something I came up with. It will double as a snapcap as I added a nylon pellet where the primer pocket is.

I've turned a few of those in .620 cal but they will not feed. I am currently working on some variations to send to Rob in hopes of getting something similar to feed smoothly. The round nose in the last picture is where I'm starting and will slowly start adding a metplat and tapered side to see how far I can go before things start to hang up.
John

Fritz454- Absolutely beautiful pictures. Those cases look fantastic. The bullets look great also. Man you have talent with that CNC center. Whose make is it?
Overkill- I suspect with a 750 gr bullet you could probably get 2800-2900 fps out of it. Maybe more.-Rob

[ 01-27-2003, 09:10: Message edited by: Robgunbuilder ]

Thanks Rob,

30 years doing this type of work I guess I've picked up a few things along the way. The machine in the picture is a Haas SL20. It has live tooling and a programmable "c" axis (the spindle). It also has a bar feeder. I turned 160 cases yesterday and today I turned your bullets on it. They are being moly coated now and will be on the way to you tomorrow, same for the brass. If there is any interest in 750 gr bullets, just to see what they will do, let me know and I'll turn a few.
Tomorrow I'll post some pictures of the different nose shapes I made today. I want to see what will feed in the 600 OK.
John

A few different nose shapes for the 600 OK. All are 900 gr.

I like the one on the left best, and the middle one is my second choice.

Have you considered a cutting shoulder like the one found on TCCI solids (made for A-Square)? To achieve it, I would envision the ogive being about .590 just ahead of the first driving band to give a Keith SWC result for the nicest cookie hole cuts one could imagine.

Just a thought. Thanks.

I think the last 2 will feed easist, and personally like the last one, on the right.

jeffe

Fritz454, Rob

I am glad that you two are shooting that thing and not me. I can truthfully say that I am not up to it.

That being said. I am greatly intrigued by this project.

Are the bullets in the photos going to be actual projectiles out of this gun? Would bullets turned out of solid copper work well?

I just want to see what this does on a real hunting trip and see the effect on a buff.

Keep up the good work, and I really do enjoy the photo updates of the project.

Jim B.

500grains



Something like what is on the far right?

Jim B,

These are intended to function as solids and copper is to soft for this application. It would expand and deform too easily. JMHO

One person shot one into oak and told me that is could be reloaded again. It had rifling marks but otherwise was in its original configuration.

John

Fritz454- Your Bullet went through 4Ft of seasoned oak log lengthwise and then about 6 inches into the mud behind the logs. The rifling marks were the only deformation visable. It could absolutely be loaded and shot again. The 600 Ok will actually feed those keith stype bullets although just barely. They could be loaded single shot. The second bullet on the left with the more rounded nose would probably feed the best IMHO. The crimp needs to be very tight and no shoulders for the bullet to hang up on.
I can't wait to see those cases! What a beautiful job that was. by the way about what does a Haas like that cost? I gotta get me one!-Rob

[ 01-27-2003, 23:20: Message edited by: Robgunbuilder ]

Rob,
Depends on what tooling you get. With a live tool machine the turret is VDI and requires non-standard tool holders. Each live tool holder runs between $3000-$4000,average. That machine is almost 3 years old and with a basic tooling package was in the lower 100K range. About the cost of a starter home in Montana.

You can see the live tool holders in the picture below. In the lower right the radial holder is easy to spot the tool is 90 degrees to spindle centerline. The axial holder is a bit harder to see it is at the top of the turret.

The radial tool is in position and if you look to the right of the turret you can see where is engages the drive.

500grains,
I'll turn some tonight.

those bullets are works of art! I had thought about doing solids like that. What type brass did you use. I would like to turn some out some day. My machine is not CNC but I got more time than money. Very nice work guys you inspire me.
Dean

Tonto,
Material is 360 half hard. It may be a bit dificult to turn any type of quantity with out a high scrap rate on a manual lathe. I'm holding OD tolerances of +/-.00015. Hard to do on a manual.

The latest bullets are below.


.510, 600 ge - .620, 900 gr

[ 01-28-2003, 05:38: Message edited by: fritz454 ]

Tonto- On a manual Lathe, your best bet is take the time and make a Form tool which cuts the base, ogive and grooves all at the same time, as well as parts-off. As Fritz454 says, otherwise you will have a pretty high scrap rate.-Rob

Fritz...
Can you make that .510 at 550 grains? I think you'll have a market between Paul and RAB and I... Rob and Nick can just take some emerycloth and buff down the final .005!!! I do still like the rounded shoulder on the .600... perhaps a little more round, to help feeding, than the .510 at 600 grains?

dang it.. those look gREAT!!!!

jeffe

thanks guys
my oldest is looking at a school for cnc machines if I cant get it maybe I can give hime some school projects once again very nice work guys.

Jeffe,
Making that .510 cal into a .505 cal is literally a 3-5 second issue. Changing the weight and nose shape is also no big deal. Once a basic program is written for a specific weight the nose shape can be changed with no more than 5 lines of machine code (depends on what needs to be done). Then some slight length changes to bring the weight back to where you want.

The 510 cal, 600 gr is for a double and feeding is a bit less of an issue. There is a .040 radius between the metplat and the tapered side. Making that a .125 (1/8") radius is the alteration of 2 lines of code and its done. To bring the weight down to 550 gr would require shortening the bullet approximately 0.25". A little tweaking and its done.

Tonto, Good luck to your son. There is a real need for trained programmers, operators, and machinists. It is a dying field. I would recommend he get some manual training with his CNC training. If you can do something manually the CNC makes it easier, more accurate and consistent. I've seen some kids come out of tech schools with CNC certifications that didn't know you have to drill a hole before you tap it. No Sh#t. JMHO

Fritz,
You wanna take me on as a shopboy, and let me work my way up to apprentence? I can do internetworking like no one else... but i have ZERO exp in CNC...

hmm, can we talk about getting some of the 510 at 550gr? really

jeffe

[ 01-28-2003, 18:39: Message edited by: jeffeosso ]

500grains,

I will be sending one of those you and Rob today. I'll get something along those lines that will work in the 600. It may be just a slightly bigger blend radius on the leading edge.

Jeffe,

I will try to get a few 550 gr bullets done today. Do you need .505 or .510 dia bullets? Which nose shape do you want. I'll post a picture as soon as I'm done.

Fritz,
I would love some 550 grain .510s, with the nose of the extreme right of the first batch of 600s you posted, and the slope like the .510 600 gr you also posted. Looking for a nice feeder in a bolt gun.
I need to pull my only 500 hawk "schuler" type bullet, which is SUPPOSED to feedwell..

thanks again
jeffe

[ 01-28-2003, 21:24: Message edited by: jeffeosso ]

DAMN!!! those are big bullets,some one get ahold of KEV,bet those flat points would work in his 50-110 express

All I can tell you guys is I've shot some of Fritz454's bullets and they are superb! I'm sure you can sell all you want to make!-Rob

Rob,
That is my plan. I need to write programs for some of the more standard calibers but I also want to provide a custom service where the customer can specify what they want and I will turn bullets to that shape. I've got some things to work out before I'm off and running.

Anyone have any suggestions on how to moly large quantities of bullets? Up until now I've been doing it a vibratory tumbler but it doesn't do a very good job on the very large bores and takes a long time. The capacity is very limited as well.

Fritz454,

My guess is that you need a rotary tumbler of some kind. Years ago when I was scuba diving, the dive shop was doing rehab on some old steel tanks that had scale inside. The shop owner set up a system where he laid the tanks on two bars that were parallel and separated by about 2/3 the diameter of the tank. The bars had rubber bushings, and one bar was driven by an electric motor. He would put enough abrasive inside so that the bottom of the tank would stay covered, set a timer and leave for the day. You could probably make something similar that would work for bullets.

Alternatively, find an old concrete mixer and trim the internal paddles down. That would enable you to tumble bullets in bulk, and then dump them out when they are done.

Good luck and nice looking bullets!

Need just one more gun,

Thanks for the idea. I actually have two large rotary tumblers for doing deburring on our machined parts. The problem with tumbling is that if the drum is large, which is what I'm after, when the bullets climb the side and then fall they fall onto each other. With light bullets it doesn't cause any damage but with bullets over 250grs it causes dents.

Right now I'm using a midway case vibratory tumbler and aside from being far too small, it takes hours to get a good coat of moly on the bullets. It is also a very messy operation. It doesn't seal very well and the moly gets everywhere.

Thanks, for the suggestion. Keep em coming.

It may not be necessary to moly coat the bullets. Barnes does not moly coat their solids, and they sell just fine, notwithstanding all of their drawbacks.

How 'bout pouring in 25 pounds of 3/16-1/8" ball bearings and fill the tumbler to ~1/3 full? The bearing would act as a not only a cushion but help to coat the bullets.

This is a great thread and really shows the talents of some of our members. I agree with 500 grains and would skip the moly coating process. I went through the same moly process with my Neco system and have since retired it. I really didn't find the benefit worth the trouble. With some bullets it's really hard to get the proper coverage. You guys are doing an awesome job.
Take care,
470 Mbogo

Frankly, I also have totally quit Moly Coating or Danzac copating bullets since I went to Rob's BORE SHINE! My secret formula for copper fouling removal. It works on my .50 Competition guns and gets the fouling out very well indeed. You need a gas mask when using it, and your skin come off, but so does the copper/brass fouling. -Rob