600 Overkill? Anyone..

600 OK... (Over Kill) is an entirely different animal from 600 Nitro Express. The only thing they have in common is .620 caliber. Naturally the 600 NE is for the double rifles, and the 600 OK for big bolt guns. 600 NE Rimmed and the 600 OK is a Belted Case.

We have had 3 such rifles here doing test work in past years, the last one was 2011 when we tested the .620 caliber CEB #13 Solids and Raptors. Two were CZs and honestly was not worth the weight in lead. Neither would feed nor function, one had to be single shot feed from the magazine, the other one had to be loaded with the cartridge slid under the bolt, and then put in the gun. Totally Useless POS.

The last one was a very well built rifle on a Granite Mt Action, and it indeed would feed and function properly.........

DSC08233-L.jpg


DSC08590-L.jpg


600 OK was developed in 2000 by Robert Garnick. It is designed and can supposedly handle 900 gr bullets at 2400 fps. It was not my mission to do any load data, but I used WW 760 for the most part from 150/WW 760 up to 170/WW 760 for the 900 gr CEB Solids and the 825 gr Raptors. I tested the 900 gr Solids from 1487 fps up to 2160 fps. The 825 Raptors from 1440 fps to 2201 fps.

I forget the exact weight of the Granite Mt Rifle, but it was at 13-14 lbs, with a 24 inch barrel.

In those days we were not really recoil shy, and I was used to shooting on average 10'000 rounds of Big Bore a year, several hundred each week doing load data, and bullet tech work. The last day shooting the 600 OK I had 22 rounds loaded up, and these happened to be the 2160-2200 fps loads. At the end of that test, I was very pleased I was finished I can tell you. Even I would not have wanted to shoot any at 2400.

At 1800-2000 fps it was not terribly punishing, it was like a big push, and of course there is a huge muzzle flip, or lift. You have to roll with it and let it do its thing, if you try hard to control the recoil and muzzle flip, it would get more punishing. And, recall, all the test work had to be done from the bench, there was no standing test work done, we had to have the closest precision possible to complete the mission, all from the bench.

We conducted other work with other bullets as well. I knew Robert at the time, and he sent several of his designs to be tested as well. If I were designing a bullet today for the 600s, I would go with something like a 700-750 gr Solid and a matching Raptor that would come in at 75 or so gr less. Run them at 2100 or so, and go about my business...........Although they are extremely effective at 1900-2000 fps, which is hi end velocity in 600 NE.

The same friend that sent his rifle down to me to be used in the test work also was a 600 NE fan, later used the bullets at great success for elephant and buffalo.

For me personally, rifles are way too big, too heavy, and I just would not carry that around. Yes, they are effective with the right design bullets, and yes, like everything else, totally useless with the wrong sort of bullet.

DSC08642-XL.jpg


DSC08659-L.jpg


DSC08617-XL.jpg


DSC08628-XL.jpg


DSC08630-XL.jpg
Well, I really love the design of your rifles in MDM and B & M. Great ballistics in well designed and thoughtfully made rifles! Where’s everyone else’s forward thinking!
 
Well, I really love the design of your rifles in MDM and B & M. Great ballistics in well designed and thoughtfully made rifles! Where’s everyone else’s forward thinking!

That's why I have a 500 MDM and .416 and .458 B&M. Coupled with Cutting Edge Bullets one does not need anything else for Africa. Other than just using inventory of one's rifles of course. ;) Regardless of how many rifles I take to Africa at a time one of them will always be an MDM or a B&M rifle.

In regards to .458 B&M, think about it, very close to a 24" barrel .458 WM ballistics with an 18" barrel, very easy to handle rifle,
 
That's why I have a 500 MDM and .416 and .458 B&M. Coupled with Cutting Edge Bullets one does not need anything else for Africa. Other than just using inventory of one's rifles of course. ;) Regardless of how many rifles I take to Africa at a time one of them will always be an MDM or a B&M rifle.

In regards to .458 B&M, think about it, very close to a 24" barrel .458 WM ballistics with an 18" barrel, very easy to handle rifle,
I’m thinking that .458 B& M with at least a 20” or 22” inch barrel. Short enough? Old habits ( barrel lengths) die hard?
 
I’m thinking that .458 B& M with at least a 20” or 22” inch barrel. Short enough? Old habits ( barrel lengths) die hard?

Talk to @michael458. With new RUM brass my 18" .458 B&M was nearing 24" .458 WM ballistics. He was concerned and did pressure tests with it and it was fine.

I have a 20" barrel on my .416 B&M. The ease of handling between it and 18" .458 B&M is huge really. But, if you want a longer barrel, go with the 20". 22" defeats the purpose of the design IMHO.

I would have no qualms about facing a charging elephant with my 18" .458 B&M shooting a 450 grain CEB solid @2,290 ft/s
 
.if someday you find yourself fortunate enough to have fired one, or even better....... to actually murder some big, gruesome, smelly bastard who has been waiting and dreaming about rubbing his jinglebobs on you face right before you die from the merciless ass whuppin he just gave you then, and only then, might you understand just what the 600 ok or his little brother the 577 Trex are just all about.

And when someone loads a 600ok with his big boy panties on and cuts that monster murder off the chain with a slug a bit better than 2 ounces you can get a 13,000 foot pound missile to do your bidding.
 
Talk to @michael458. With new RUM brass my 18" .458 B&M was nearing 24" .458 WM ballistics. He was concerned and did pressure tests with it and it was fine.

I have a 20" barrel on my .416 B&M. The ease of handling between it and 18" .458 B&M is huge really. But, if you want a longer barrel, go with the 20". 22" defeats the purpose of the design IMHO.

I would have no qualms about facing a charging elephant with my 18" .458 B&M shooting a 450 grain CEB solid @2,290 ft/s
I’m sure your absolutely right about the shorter barrels. But I’m not going to buy a rifle with that short of a barrel without shooting one first. There is the issue of sight plane, which may be not much of a factor at close range? Don’t know? Have to shoot a short rifle first?
 
.if someday you find yourself fortunate enough to have fired one, or even better....... to actually murder some big, gruesome, smelly bastard who has been waiting and dreaming about rubbing his jinglebobs on you face right before you die from the merciless ass whuppin he just gave you then, and only then, might you understand just what the 600 ok or his little brother the 577 Trex are just all about.

And when someone loads a 600ok with his big boy panties on and cuts that monster murder off the chain with a slug a bit better than 2 ounces you can get a 13,000 foot pound missile to do your bidding.
Oh, your teasing me Von S.! I’ve come close to your scenario, but he was two legged with a 9mm! But, the Taser got him from behind! Where was the .600 OK when I needed it? I know, in someone’s gun safe! Ha! Ha! Ha!
 
I’m sure your absolutely right about the shorter barrels. But I’m not going to buy a rifle with that short of a barrel without shooting one first. There is the issue of sight plane, which may be not much of a factor at close range? Don’t know? Have to shoot a short rifle first?

Well, next time I visit my son at Erie, CO, if you haven't moved on it I will bring it for you to shoot.
 
Dont hold me for my word, I just may be mistaken. But I think that holland and holland built the last .600 rifle, with certificate for the owner that it is last of their .600.
Then, .700 was invented, for this rrason, so holland and holland may still build their .700 but not .600 honoring their certificate.

However, other makers may build .600, no problem.

Question will remain, what is really biggest practical, usable, reasonably big, stopping caliber? Somehow i doubt for .600 or .700. Perhaps, 577?
 
...

Question will remain, what is really biggest practical, usable, reasonably big, stopping caliber?...

For me it is the largest caliber that I can shoot confidently and would not hesitate to face a charging elephant at 15 meters. That happens to be my .500 MDM wildcat. I don't have enough mileage on my .500 NE to say the same though by the time I face another elephant next year this time I should feel the same about it.

Not sure about the .577 as I have not handled it. I know the .600 or a .700 fail the practical/usable test due to weight alone as I would not want to lug them around for miles each day.
 
Well, next time I visit my son at Erie, CO, if you haven't moved on it I will bring it for you to shoot.
I’m in!!!
 
I have/had many .600s both in double and Bolt ...AHR and Bijou Creek Customs...Building another now for Alaska in Synthetic and about 9pds with a 16" barrel...aka GRIZZILA ...Will also be used for Lousiana hogs with a Big 56mm Schmodt Bender for late evening feeder hunts for hogs!
I find when in the field I never feel them go off...but recoil has never been a issue for me...always shot 900s but next one will be using CEB 825s at 22-2300fps...Should cut them piggy's on half! (Or drop a Brownie or Big Alaskan Moose where he stands!)
I have had 600s with 24" down to 16" barrels and we have chronied them and with the much larger Bore dia ,we find usually no more than 10-15fps per inch loss...nothing like say a 300 Win Mag could loose up to 50ft per inch depending on loads! We are actually building 2 right now..1 will be 20" and Grizz 16"...
I will try a post a video here of Mike my Smith testing out the Rogue..my other 16" 8.5pd .600 Ovekill...amazing display of "horsepower" by drilling big stumps..5 gal buckets of water and a 55gal drum of water..he actually shot it in the center and it knocked it over!!!! Think about how hard it would be for a man to push a full drum over by pushing it in the center! Next to impossible other than from Clint Walker! Lol
Pics are both 600s by Bijou Creek...the pretty one is gorgeous piece of wood and all the bells and whistles! 22" barrel...the laminated one is 16" and a tad over 8pds...its the one used in the attached video..ENJOY!
Here is the link...
20181115_224008.jpg
FB_IMG_1586607317456.jpg
 
600 OK... (Over Kill) is an entirely different animal from 600 Nitro Express. The only thing they have in common is .620 caliber. Naturally the 600 NE is for the double rifles, and the 600 OK for big bolt guns. 600 NE Rimmed and the 600 OK is a Belted Case.

We have had 3 such rifles here doing test work in past years, the last one was 2011 when we tested the .620 caliber CEB #13 Solids and Raptors. Two were CZs and honestly was not worth the weight in lead. Neither would feed nor function, one had to be single shot feed from the magazine, the other one had to be loaded with the cartridge slid under the bolt, and then put in the gun. Totally Useless POS.

The last one was a very well built rifle on a Granite Mt Action, and it indeed would feed and function properly.........

DSC08233-L.jpg


DSC08590-L.jpg


600 OK was developed in 2000 by Robert Garnick. It is designed and can supposedly handle 900 gr bullets at 2400 fps. It was not my mission to do any load data, but I used WW 760 for the most part from 150/WW 760 up to 170/WW 760 for the 900 gr CEB Solids and the 825 gr Raptors. I tested the 900 gr Solids from 1487 fps up to 2160 fps. The 825 Raptors from 1440 fps to 2201 fps.

I forget the exact weight of the Granite Mt Rifle, but it was at 13-14 lbs, with a 24 inch barrel.

In those days we were not really recoil shy, and I was used to shooting on average 10'000 rounds of Big Bore a year, several hundred each week doing load data, and bullet tech work. The last day shooting the 600 OK I had 22 rounds loaded up, and these happened to be the 2160-2200 fps loads. At the end of that test, I was very pleased I was finished I can tell you. Even I would not have wanted to shoot any at 2400.

At 1800-2000 fps it was not terribly punishing, it was like a big push, and of course there is a huge muzzle flip, or lift. You have to roll with it and let it do its thing, if you try hard to control the recoil and muzzle flip, it would get more punishing. And, recall, all the test work had to be done from the bench, there was no standing test work done, we had to have the closest precision possible to complete the mission, all from the bench.

We conducted other work with other bullets as well. I knew Robert at the time, and he sent several of his designs to be tested as well. If I were designing a bullet today for the 600s, I would go with something like a 700-750 gr Solid and a matching Raptor that would come in at 75 or so gr less. Run them at 2100 or so, and go about my business...........Although they are extremely effective at 1900-2000 fps, which is hi end velocity in 600 NE.

The same friend that sent his rifle down to me to be used in the test work also was a 600 NE fan, later used the bullets at great success for elephant and buffalo.

For me personally, rifles are way too big, too heavy, and I just would not carry that around. Yes, they are effective with the right design bullets, and yes, like everything else, totally useless with the wrong sort of bullet.

DSC08642-XL.jpg


DSC08659-L.jpg


DSC08617-XL.jpg


DSC08628-XL.jpg


DSC08630-XL.jpg
Just joined this site...look forward to all the ".600 Stuff" ! My favorite caliber now!
 
Screenshot_20200628-062744_Messages.jpg
614978960.jpg
Here is a .600 Overkill in the making..Bijou Creek..we doing 2..both Synthetics..One is Brown and other is TAN ..1 with 16" and other 20"..about 9 pds unscoped..Waiting on Barrels..
THEN THE FUN BEGINS!:A Bravo:
 
Considering a stopping caliber such as the .600's is a huge endeavor.
Not much the .600's are doing that the .500's aren't doing...and at a considerable cost savings.
Why a .600 and not one of the more popular stopping calibers like .470, .500 or .577?
Are the deer in Michigan really THAT big?
Huge endeavor for many...but not for all...I worked my way up to them over the years and hunts...then kept going to 700...8 Bore..7 Bore and then finally my 4 Bore Double the Mastodon! ...So will I get a 2 Bore? Hell no what ya think I'm crazy! Lol
(Actually my friends 2 Bore double (150 Caliber and 3500 grain bolders!) Is 47 pds and not practical for a long day of tracking buff or elephant!Pic shows my 700NE..4 Bore and King Kong Slayer 2 Bore!!
FB_IMG_1560645442333.jpg
 
I AGREE...they have a mission but if the rifle is to heavy it's no fun in Africa or Alaska...Heated long tracking jaunts or Mountain treks for
Screenshot_20200406-164439_Messages.jpg
Bears ! My latest rifles of the last 12 years are lighter and shorter...esp my Alaskan Rig in 500Jeff...6.5 pds and 36" long! 16" Barrel and Laminated stock slings 570s at 2150fps and has taken two Cape Buff and One Brown Bear...The latest 600s are under 9pds..add a Big 56mm Bender Scope for feeder hogs and it's about 10.5...but for Africa no scope or a 9 ounce Leup 2.5X
Shown is the Grizzinator 500Jeff mentioned here!
 
20181117_202120.jpg
Wow! I’m going to stick with my 505 Gibbs as the most gun I carry into the bush.
I like the 505 Gibbs ALOT! Great Cartridge with lots of potential! 600s at 2300fps did the trick over and over for me!! Wise choice!
That's my Frank Wells Custom on top and my Browning .458 below it in Tanzania!
 
Interesting rifles. It is sort of the choice between a broadsword and a rapier. I much prefer a rapier. I have fired a .600 (and a .577, 4 bore, etc, etc.) and they are unique hand held firearms. I just don't get the purpose of such a rifle for a client, and I have never seen the advantage in taking one hunting. Indeed, with respect to the hunting I have done, they would actually be a handicap. I hunt Africa with a tiny little .375. I do it not because I can't shoot bigger rounds (heck, I own several 40's), but because it is the best choice for me during a mixed bag safari that includes buffalo. Next April I'll be on the Kamchatka hunting the largest brown bears in the world. A .375 with a 300 gr bullet seems just about ideally lethal for an animal that may be at 25 or 250 yards when I take the shot.

All that said, that is my personal set of conclusions. None of that has anything to do with another's. And none of that has anything to do with the fascination the truly big bores enspire.
 
Last edited:

Forum statistics

Threads
58,031
Messages
1,245,828
Members
102,546
Latest member
MitziLohr4
 

 

 

Latest profile posts

Grz63 wrote on roklok's profile.
Hi Roklok
I read your post on Caprivi. Congratulations.
I plan to hunt there for buff in 2026 oct.
How was the land, very dry ? But à lot of buffs ?
Thank you / merci
Philippe
Fire Dog wrote on AfricaHunting.com's profile.
Chopped up the whole thing as I kept hitting the 240 character limit...
Found out the trigger word in the end... It was muzzle or velocity. dropped them and it posted.:)
Fire Dog wrote on AfricaHunting.com's profile.
2,822fps, ES 8.2
This compares favorably to 7 Rem Mag. with less powder & recoil.
Fire Dog wrote on AfricaHunting.com's profile.
*PLEASE NOTE THAT THIS IS FOR MY RIFLE, ALWAYS APPROACH A NEW LOAD CAUTIOUSLY!!*
Rifle is a Pierce long action, 32" 1:8.5 twist Swan{Au} barrel
{You will want a 1:8.5 to run the heavies but can get away with a 1:9}
Peterson .280AI brass, CCI 200 primers, 56.5gr of 4831SC, 184gr Berger Hybrid.
Fire Dog wrote on AfricaHunting.com's profile.
I know that this thread is more than a year old but as a new member I thought I would pass along my .280AI loading.
I am shooting F Open long range rather than hunting but here is what is working for me and I have managed a 198.14 at 800 meters.
That is for 20 shots. The 14 are X's which is a 5" circle.
 
Top