All this talk about 257roy then Jeremy's 6-06 AI have got me thinking about a hot-rod 6mm.

I have a 280AI rem 700 set up to shoot 160 class bullets it has a muzzlebreak 28" barrel ,thinking there is a little gap in my arsenal -no super velocity flat shooting barrel burner coyote zapper .
I want to make the 280ai a switch barrel -want to learn how to headspace a barrel on and so forth .I'm interested in shooting bullets from 65 to 95gr not the long high bc stuff ,the 87gr vmax looks good with its .400bc but see that many people like the 70gr nbt [dober].
So tell me what you know about these and how they work for you please .
Thanks for your time.
Mike

Love playin' with my 6-06. Built on a winny pushfeed. Runs the 85 TSX and the 87 V-Max same/same so the vmax makes a great practice bullet. Kills all outa proportion to the caliber. Just a sweet little round.

I've done the 6x.284 thing, sort of on the cheap and a little at a time. Started out with a short action 700 ADL, dropped in a 1-14" twist PacNor barrel with a custom contour. Later I switched stocks and BDL-ized it.

It never fed super smooth but it wasn't too bad.

I shot mostly 70 grain ballistic tips over 58 grains of RL19 in Norma 6.5x.284 brass I'd necked down. That was pretty much the limit, primer pockets were loose at 5-6 rounds. I shot some 65 grain VMAXes over the same charge. Wasn't quite as accurate but still at 300 yards my target was gonna die and the splat was more impressive.

If you're going with a long action, 6x'06 will be cheaper so far as the brass goes .. start with WW .25-'06 instead of expensive Normal 6.5x.284. It should feed smoother, too. It'll have a little more case capacity, in theory be a hair faster yet.

Tom

IMO the 6/06 is the way to go, and the 6/06 AI would be second.

I'm on my 2nd 6/06 barrel and I really like the round. While I don't know many that have had a AI version I'd say it'd be a very good one.

The non AI should feed a bit better for the most part.

The 6/284 is a good round but I'd not put one in a long action and if I was going short action I'd do a 243 AI instead.

To date, I've yet to see a rifle chambered for any 284 based round that fed to my satisfaction.

Dober

Kind of thought about something along the same lines 25-06 or maybe a 6mm AI would that gain anything over the 243 AI could go short or long action 700? I would just as soon have something that will reliably feed out of a box magazine.

I played with a 6/284 for deer for while and it worked good, but in my experience the 257 was a good leap up in the right direction. It is now my go to deer cartridge. If I was building on a short action a 6/284 would be my choice, but built by a gunsmith who had the time and knowhow to make it feed nicely.

6mm and 6AI would work fine in most short actions and would be good choices if one did not want to mess with a 6/284. Either would give a useable velocity increase over a 243.

I've been doing some research on the .284 case and it is stated on the web quite a bit that it doesn't feed real well.Seems most people think it's obviously the rebated case .
I went over to savage shooters forum -those guys do a lot trying/testing on different cartridges .Found info on of these cartridges and a lot of people like the plain 6-06 for its simplicity.

If you are going to build on a 30/06 length action and want speed, there is no reason not to just go 257WBY, IMO.

I am no expert on 6/284's having only built and had 2, but they fed well and were terrific short action fun cartridges.

Love my 6/284 and it feeds nicely. I on the other hand have always wanted a 6-06. My 6/284 has been so awesome i havent gone the 6-06 route yet.

When talking about the 6mm Hot Rods, I seldom hear talk about the 240 Gibbs. I have been shooting one for quite a few years and love it! Feeds good, fits in Mausers perfectly and I get 3600-3700 FPS with 85 gr. bullets! Case life is very good,(seems like forever), and it is kind of fun fire-forming! I suppose using 62 grs. of powder makes it not nearly as efficient as the other hot 6mm's! That being said, the 6-06 or AI version sound very interesting! How will they compare to the Gibbs?
Any input will be appreciated !
Thanks,
Ken

I looked at the 240gibbs on Steve's pages [cartridge dimensions] -pretty sure the gibbs takes the '06 cartridge as far as it can go.
Someone on longrange hunting had a gibbs -can't remember the caliber -but the short neck of the cartridge doesn't do to well with the long high bc bullets.
They checked a loaded round for bullet runout then ran one through the magazine and into the chamber -extracted the round and found a good bit of run out.Probably from the long bullet going up the feed ramp.
Single loaded the long rounds.
Probably wouldn't be a problem with shorter length bullets though.

Mark -i just sold a 25cal rockcreek barrel because i've decided to go w/a .264 bore size when my 25-06 barrel goes south.
That 257roy thread sure has me thinking -i didn't know you could get that kind of performance from the Roy.

Which ever hot rod 6mm i choose will be to learn the switch barrel stuff ,so i'll have to get a 6 or 6.5 -284 case and see how they cycle through my gun.
All the cartridges mentioned would make great coyote thumpers with plastic tip type bullets and the recoil should light also .
Thanks -Mike

The 243AI is a potent round. But the 6mmAI blows out quite a bit more and shows a considerably more increase in performance. With a good barrel and chamber 70's will be doing over 4100 without much trouble. That cartridge would be my pick. The.240 Gibbs is dynamite on rockchucks but I replaced mine with the 6AI barrel. Velocities are comparable and brass will be a whole lot easier.

IMO, if you've been running a 70 @ 4100 out of a 6AI and not had any trouble then the key word is yet. That is a crazy amount of smoke to stick behind that bullet in a 6 AI.

Really guyz, either your clocks are fubar or you're just beggin to be called old one eye...!

Dober

Actually no, you're wrong about that. But what they say about opinions is true.

Cool deal, let er buck buddy!

And yes there is one born every day...!

I once was the president of the red liners club so I think I see where you're coming from. Trust me it really aint worth it.

Dober

No "buddy", you ASSume but really don't know where I'm coming from.

Hot rod 6mms and no one has mentioned the 6mm STW...

Like I said, if it makes you happy then Powder River let er buck. Hint....wear safety glasses.

By the way, not wanting to assume anything here, why don't you tell us what your burning behind that 70 to get it to 4100? Also what length barrel?

I've run enough 6/06 barrels to know that 4100 out of a case that's smaller isn't normally gonna get one to 4100.



Dober

Now ya done it Dober...grin...

Probably the end of this thread...grin...

Yeah G, we should talk about something funner like Swifts and deer and now they don't work..

Enough "BG", ballistic gack eh...

Dober

A lot of armchair quarterbacks around here.

That rifle belonged to a good friend. There's more, but the basics are..... 26" Shilen, 14" twist. Fireform load was 50.5/760/70BT@4050. Formed load 51.5/760/70BT@4150. Oehler chrono. No overpressure with either load. The guy who now owns that gun is shooting 80's @ 3800 with RL19 powder. My barrel is 30" Krieger 12" twist, same reamer.

Hey I'm happy for you, sounds like you know what you're doing

Dober

Ask him what a 223AI will do with 40's(grin)

Man I have to get me a Oehler...........

You think you're being cute.

40gr BT - AA2015 powder

27.6 - 3957
27.9 - 3977
28.2 - No reading, forgot to reset
28.5 - 4096
29.0 - 4192

All loads pretty much the same accuracy.
25" Schneider 14" twist - chamber length 1.765", .250"nk, 0 freebore - IMI brass, 7-1/2BR, bullets have thin film Lee Lube.

The velocities are more sedate than I recall. Good on ya.

I'm not doubting your word, not trying to start a fight, but I am doubting your chronograph's accuracy. You're claiming 200 fps faster with a smaller case and I was at a pressure level where I was only getting 4-5 loadings per case before new primers wouldn't stay in the pockets. Have you verified those readings with another chronograph?

Tom

I always wanted a 6mm Rem AI, so I had a reamer ground by Pacific Precision, non turn neck, zero freebore, 0.2435 throat, with 1 1/2* leade angle.

My first rifle was on a Win Model 70 Stainless action, with a 26" Max heavy varmint contour in a 14 twist.

I had previously had a flock of 243AI's with 12 twists, so I just added 3.0g more 760 to the fire forming loads in Win brass with Fed 210's.

4 rounds to sight in, then shot a 3 shot cluster fireforming in the high 3's with the 70g Ballistic tips at 4050 fps, zero pressure.

On the formed loads, I added 1.0g more powder, and got 4150 fps, still no pressure, neck sized the cases for 5 firings, then full length size...primer pockets still tight. Obviously this is a "fast" barrel. Accuracy was in the high 2's and low 3's for three shot groups.

On my next barrel, I got a steal on a Douglas stainless match, Max Heavy varmint contour, in a 1-10 twist, chambered it using the same reamer, 26" finished length.

Took off to the range with the same lot # of brass, same lot of 760, same lot# of primers, new brass to fire form. First round out of the barrel, and I darn near had to beat the bolt open on the side of the bench using the same fireforming load as the other rifle. Backed way off on the powder charge. The accuracy load ended up at 3850 fps(vs 4150 in the other barrel), but there is a fly in the ointment...cases need full length sizing & after 2nd firing, and pirmer pockets were getting on the loose side. The accuracy node was at 3850, but with wrecked brass. I had to back it down to about 3750 which was 5/8" accuracy.

I am not slamming Douglas barrels, this is just an example of how a different brand or a different barrel with a different twist rate can mix pressures and accuracy up a LOT!

In my experience, it is not prudent to judge a caliber based on one barrel's experience.

I use an Ohler 35P that has two chronographs to check against each other. I also have a Pact Professional.

It is very easy to get 3800 out of the 75g V Max in a 6AI, depending on the barrel.

I have a buddy in Kansas that is shooting the 80g Sierra Blitz in a Shilen 26" 6mmAI, cut with my reamer, in a 14 twist that is shooting 3800 fps with R#19 (he's a dog shooter).

TOM, my loads in a 27", 1-12 twist 223AI loaded with the 40's with N133, 7 1/2's, IMI brass, zero freebore chamber with .2245 throat mimic Ackman's. I'm getting 4150 out of the Naked 40g NOslers, shooting very tiny groups. No other powder other than N133 will get these kinds of speeds with extreme accuracy. Benchmark, H322 is about 150 fps slower. Since N133 is hard to find(and costs more), most folks will never see these kinds of velocities in their guns.

I get 3800+ and 3700+(N133 ONLY) out of the 50's in the 27" and the 23" respectively, 27" is a 12 twist and the 23" is a 14 twist.


Hope this helps

Keith,

you've quoted some pretty high velocities in a number of different cartridges which seem to exceed what is reported by others shooting the same cartridge. You have said several times that you aren't exceeding pressures. Are you using a strain guage or something similar to check pressure?

It may seem that I am getting much higher velocities than others, but I am sure that I am not talking apples to apples. For instance, a change in twist rate increases/decreases pressure (while many, many people say that it does not, I know from hands on exprerience that it does), barrel length, Chamber design is of major importance, and not the least the use of specific powder/brass/primer combo's.

Brass is the weak link in any cartridge, just watch for pressure signs. I have found that Federal and Rem brass are a little softer than Winchester, hence Win will take more pressure (I'm talkiing loads where you only have to neck size the cases). I won't shoot Norma brass because it is Soft.

Most of what you read is in factory rifles with huge sloppy chambers or in rifles. Comparing a factory rifle to a rifle with minimum spec chamber, custom barrel, is not comparing apples to apples, they are different animals. Of course I do shoot a lot of factory rifles.

I have also found that three groove barrels seem to be faster than their 5 and 6 groove when cut with the same reamer, using the same lot # of powder, etc.

My first real eye opener on differences in barrels was when I had a Rem 223 Sporter barrel opened up to a 22/250AI when it was a brand new barrel. I could not even come close to the velocities that I got with a Hart Stainless, same reamer was used. Next FUBAR was with a Rem 243 Sporter, that I had 1/2" cut off the breach end, then chambered with my 243 AI reamer. The factory barrel was slow compared to the Hart Stainless versions of the same type.

There is no solid evidence that I know of to leade one to think that the inside Bore Dia.(+*-.0002-.0003) height of lands, design of lands might make a monumental difference in speed and pressures, but I do know that these minute details may mean a lot.

When you read of some guy that gets fantastic accuracy with speed, it is a good idea to get him to elaborate on how he does what he does. I learned the techniques from gunsmiths and other shooters a long time ago, nothing new...we all learn from each other. All the guys that I shoot with that duplicate my results with their rifles would not dare post their results on the internet...too many guys that have no experience with wild cats that are closed minded and are experts because of what they have read...that is human nature.

The way that I and most people that work with wild cats judge safe pressure is when we can neck size the cases several times(or just bump the shoulder back .002 and get 12+ firings on a case) on your accuracy load. Our Remington's and custom actions don't blow up. I have some Rem 700's that are on their 5th and 8th barrels, with many on their 2nd and 3rd barrels.

If a guy were considering putting a custom wild cat on a flimsy action, break open of any kind, or a falling block, that person would have another entire set of pressure rules that would apply to him. I like strong actions for obvious reasons.

Hope this helps....

WHY DO YOU ALWAYS BUT IN ON A POST THAT YOU KNOW NOTHING ABOUT AND HAVE NEVER DONE ANYTHING CLOSE TO WHAT WE ARE TALKING ABOUT AND PUT IN IN YOUR STUPID OPINIONS
I HAVE A VERY GOOD SUGESSTION FOR EVERY ONE ON THIS SITE IS TO BLOCK ANY OF HIS POST JUST MAYBE HE WILL LEARN TO KEEP HIS NOSE OUT OF EVERYONE ELSES BUSINESS.
IGNORE IS THE BEST THING TO DO WITH HIM.
NEVER REPLY TO ANY POST HE DOES OR NEVER AKNOWEGE HE IS HERE.
I REALLY THINK THE NAME SHOULD BE DUMBER NOT DOBER.
HE MUST REALLY LIKE SUCKING ON HIS TOES BECAUSE HE STICKS HIS FOOT IN HIS MOUTH WITH EVERY POST HE MAKES

You may or may not be right, but he does error on the side of safety. I'd not condemn what he says or what you are doing until the loads in question come with proven pressure figures.

Ummm...

Right...

A suggestion? Proof reading? It means you read before you submit...

My first post on forum!
One of my first wildcats was a .243-06, built not long after the .243 Win arrived on scene. I love the .243 for its lightning strike killing power on whitetails and smaller game, but it fizzles out quickly over 300 yds. Around 1960, I reground a 06 AI reamer to what my brothers called the .243-06 Brewer Bastard. Almost full 06 length but shorter neck and shoulder moved forward to exactly .243 dimensions.
First rifle, Douglas barrel 26" light weight sporter on new surplus $18.99, 1909 Peruvian. This gun still is about as accurate as any I own. after 50 years and (guessing 2000+) 100 gr. Hornady bullets, I use it to take deer, coyotes, armadillos and other varmints in the pastures around the house up to about 400 yds.
Last time I benched it, had some dime size groups. Hornady 100 gr. over xx.x grs. IMR4831 in fire-formed Win. brass give vel about 3400. This load is stiff, but brass life is good with silk smooth extraction, and after 50 years the old Mauser action is very tight.

forming brass for it is more complicated than 6mm-06 since the body is about 1/8 longer. Similar I would guess to the 240 Gibbs. I designed it to reload in standard .243 dies since way back custom dies cost a month's pay.
If you need a reach out to 400+ get um gun, a 6mm x 06 should be high on your list. When I learn how, I'll post photos.
Thanks for helping an old, almost blind, guy reminisce.
ancient rifle smith
"Old enough to be your Granddad but young enough to be a friend."

Ancientriflesmith ,

WELCOME TO THE FIRE !!

" Shortly before the 243 came out " -this ain't your first rodeo in other words .
Glad to have you -jump in anytime .
Mike

Yepper welcome to the Fire Ancientriflesmith!

Dober

My hot 6mm is a custom 240 WBY
It is-
Rem 700 stainless action (was originally a 30/06)
Lilja barrel, 26"
McMillian stock, Rem hunter
Topped with a Leupy 4-12 AO

I have shot half a dozen antelope with 90 and 95 grain bullets. Most of them ran 50 or so yard after the shot.
And I have shot three coyotes with 70 gr ballistic tips.
They were instant death.

Brass is over $1 a piece, other than that, it's a great cartridge, in my view.

Dale the main reason I first built my 6/06 was for yotes. I had a long action and I was gonna go Swift when a mentor of mine slapped me around and told me to go with a 6.

I've used the 70 NBT quite a bit on chucks/yotes/lopes/deer and a few other critters. It is an absolute hammer!

Dober

Pardon me if I said before the .243 came out...... I should have have not long after the .243 was available. Any way yep it ain't my first rodeo but my be towards my last.
I started hunting back in the 40s and for several years kept meat on the table with a Model 68 Win Single shot 22LR. Done my first bullet casting and loading with Winchester molds and reloading sets for 25-20 and 32-20 in 1949. Started building custom rifles about 1960 and continued till last year. My eyes got bad so I had the latest eye surgery and now am all but blind.
My brother "Arky Jack" on some forums- passed away a year ago some of you likely corresponded with him. Probably was not a more experienced handloader around. We lived and talked guns and ammo our whole life. really lonely without him and nobody to call everytime I mess with some new gun or cartridge design.
I don't play on this infernal machine much but I do like to read about some of the things you youngens are playing with.
I'm not the expert some of you are, but have built a few hundred guns in almost every caliber of any importance. I'd be happy to offer my two cents worth to anyone with a question.
My favorites are 30 and 35 Rem. 300sav, 284 win, 45-70, 338-06 AI for pigs at distance, 35 Whelen AI for elk and bear in Bob Marshall Wilderness (Griz country). Never seen much need for belted brass that blows your shoes off every shot. But a 6mm in one form or another is what I manage critters around the house with. In fact two are in reach of where I'm sitting a H-R Handy Rifle 243 and the Bastard .243-06
Guess I need to start keeping these short or they'll run of space on the pages.
ancient rifle man

When was the last time you hunted the Bob and where did you go in?

Thx
Dober