a while back my father gave me a rifle he had had built in 22 CHeeta MKI (40 deg) i haven't played with it any yet but would like to start. i have 20 rounds of formed brass and 3 more boxes of the BR 308 cases with the small primer pocket. if any of you guys have any experience with the cheeta please share it with me. loading data, stories, performance. the smith who built it worked out some loads with 50-55 grn bullets and IMR 4350 powder but i'd like to hear what other are useing. also any case forming tips(actually, the whole process) would be welcome since i didn't form the cases i have(i DO have the dies)

thanks in advance

The 22 Cheetas (1 and 2) are interesting cartridges but not real practicable. If you keep the chamber pressure down at the parent cartridge level (50,673 psi) it’s no more than a 22-250. If you step up the pressure by 10,500 psi, it’s almost a 220 Swift. To get the “hyped, legionary” velocities, you need to step up that pressure even more. It wouldn't be a bad cartridge at the lower velocities though.

thanks for the reply. i'm not really concrened with getting max velocity. i don't push anything to the maximum. but the rifle was given to me by my father, it's real nice looking, unusual, and i'm hoping for good accuracy and some fun shooting. i would be satisfied with 22-250 speed but a little more would be good also. i'm just interested in what experience others have had with it AND hoping somebody will go over their case forming process for me.

good hunting

Have fun with it.

I did some load work with a Cheeta years ago I believe it was the Mk1 it had a shoulder like my AIs. A guy I worked with had one built. If I remember on top of fireforming the shoulder we also had to turn the necks.

What we found was that if we tried to honor the parent case pressure limit we simply burned more powder to almost reach my 22-250. So we ignored it. Trying to really push light bullets we had many never reach the target. I think they later tried 1:16" twists on the cheeta.

As Mick said at 308BR pressures it is almost a 22-250 at 60,000 it is a 220 swift using more powder.

I think we were using 50gr Nosler I believe and H414. But I have slept a lot of times since I fooled with one.

Mick,

I lead a sheltered life out here in Idaho. Tell me why a significantly larger case (interior volume) at the same pressure does not provide more velocity.
With your logic, a 22 Hornet at 53,xxx PSI should match the Swift.
I've always believed a bigger case was the direction to go when you want more velocity...

Have things changed since I left PS?

Rich

I have no experience with the Cheetah.

That being said, it is simply an overbore. I have good experience with those in 7mm RUM and .264 Win Mag. VERY SLOW powders are the name o' the game there.

Why wouldn't this be the case with the Cheetah to obtain max velocity?

The biggest problem, that I encountered with the Cheetah, was eratic ignition of slow powders and small primers in cold weather. I had better luck with cases made from 243 brass.

according to the smith who made this rifle and worked up the only load data i have for it, ignition problems due to sm primers are why he went with 4350 instead of something slower. i'm going to give his load a try but as soon as the neck turning mandrel gets here i'm also going to make some cases with lrg primer pockets and try some slower powders. it's going to be interesting but if i can make a nosler 60 grn part shoot good enough i may see what they do on these 80 pound does we have here. any load data anyone? another thing, the barrel has a 15 inch twist....what is the heaviest bullet that might work....i hope the 60 grn part is not too long.

quote:

but if i can make a nosler 60 grn part shoot good enough i may see what they do on these 80 pound does

If it were mine I would scrap the 308BR brass. Shilen says a 15 could be used with a 55gr at 4100. A 60 Part is the same length as many 55gr.A Part sure isn't needed for an 80# doe. Either way you are going to need velocity. Trouble igniting as well as brass designed for lower pressure don't fit with that. I like your idea of 243 brass.

For your info QL gives max velocity with nothing really slower than Norma MRP, 7828 etc. Even in a 26" barrel.

Rich the Cheeta has simply reached the point that more powder isn't better. If more powder always meant more velocity there would be a lot of wildcats for 224s with cpacity far greater. The 06 based cases, the 284s etc when you get down to 224 simply burn powder and barrels with not much if any gain over something like the swift.

i hadn't thought of the BR brass being for lower pressures. i have a pillow case full of once fired 243 brass so i'll pick and choose 50-100 good cases and, when the neck turning mandrel gets here, i'll form them up and turn the necks to get clearance in the chamber neck(neck of the reamer measures .252)

with all this case building to do, shooting is still a ways down the road but i'm still wanting actual load data if anyone has any. i have a fair variety of powder...RL22, RL25, H4831SC....nad don't mind buying another powder specifcally for this cartridge.

thanks again for everything so far and whatever else you guys can help me with.

quote:

hadn't thought of the BR brass being for lower pressures

Don't put major $$ on this I was under the impression that the Cheeta was loaded to around 51,000 because of the brass. Then again the 22BR and 6mmBR are loaded to around 58-59,000. So I could be all wet. I do know we had some pressure issues but without a way to measure it heck maybe we were way high. I still think a large primer would help getting a full case of slow powder started.

As I said QL gives max velocity to MRP which should be real close to your RL22.

Data for the 224TTH and 224 Clark should be close.

For deer you could also try the lighter weight tsx's 45grn and 53grn.

quote:

Originally posted by Idaho Sharpshooter:
Mick,

I lead a sheltered life out here in Idaho. Tell me why a significantly larger case (interior volume) at the same pressure does not provide more velocity.
With your logic, a 22 Hornet at 53,xxx PSI should match the Swift.
I've always believed a bigger case was the direction to go when you want more velocity...

Have things changed since I left PS?

Rich

Rich - From our days at PS, I seem to recall you having about as much actual field experience with the Cheetah as anyone... Why don't you post some of the data you used, and maybe refer to an article some can dig out & read, if you wrote any specifically on that chambering?

And, yes, I agree a larger case burning more of a slower burning powder (and thereby maintaining the SAME pressure as a .22-250 for a longer pressure dwell time) should produce higher velocities (and shorter barrel life, due to the longer exposure to 3,000 degree temps in the throat).

If that takes large primers, well that's why we develop loads....to find out what works best in our rifle and chamber.



"Work is the curse of the drinking class" - AC

Hey Rich & AC. What was the pressure limit you guys were using on the Cheeta or 308BR case? I did find some of our data. For some reason the guy that owned it was told to load to around 51,000 with the BR brass. At that pressure we we were using around 44gr of H414 a 55gr Nosler and getting around 3620 from a 24" my 22-250 MKX would send a 55gr downstream at close to 3700. We took H414 to just over 47gr got right at 3850 with the 55 but were having brass issues. A swift should get close to that. A 35% increase in powder was gettng us 4% in velocity.

Maybe todays lighter bullets can handle 4000 plus. For my $$ if I was going to build a larger capacity 22cal I'd go with a fast twist and shoot heavier bullets like they do in the 225TTH.

Please educate this old fart. Other than the 30BR how was the Cheeta's different than the various 22-243 of the day?

Paul - I am not the .22 Cheetah guru. I seem to recall Rich as having been one of them from about 20-25 years ago, though that could be a memory phart on my part.

I still have a bunch of varmint rigs, but haven't found anything they won't do if I take the right one. So, I have pretty much discarded most of my wildcats of any parentage in that realm. Used to have a lot of wildcats, but that was then....

(Currently in varmint rifles I have .17 K-Hornet, .17 Rem, .22 LR, .22 WMR, .22 Hornet, .22 K-Hornet, .222, .223, .22 PPC, .22 BR, .225 Win, .219 Don Wasp, .22 Sav HP, .22-250, .220 Swift, .243 Win, .244 Rem, 6 PPC, 6 BR, .250 Sav, .25-06, .257 Wby...and that's just off the top of my head. Would have to go look in the gun vault to provide a full list.)

I don't think there's any varmint task that can't be done with at least one of them....other than Ele, Buff, or Rhino in the garden, which is not a for-real problem here in Cave Creek, AZ.)

Best wishes,

AC

“Tell me why a significantly larger case (interior volume) at the same pressure does not provide more velocity”.

Interesting question Rich.

Cheetah Mk 1, volume 54.0 grains water. 50,763 psi P max.

22-250 Remington, volume 43.5 grains water. 58,740 psi P max.

For the Cheetah and a 22-250 to be compared we need to use a powder that works in the 22-250 and the Cheetah. In no way is IMR 4064 an ideal powder for the Cheetah but I’m using it because it works will in the 22-250 at a 100% fill rate and doesn’t exceed its P max. Right from the get-go the Cheetah has to exceed its P max to achieve the same pressure as the 22-250 (which is all I was talking about in the first place).

Cheetah Mk 1, 57,288 psi, 3794 fps.

22-250 Rem, 57,657 psi, 3693 fps.

Looks like you're right, the Cheetah beats the 22-250 by 101 fps. Interesting. 100 fps doesn’t add up to much.

Going the other way, stepping down the 22-250 pressures to the Cheetah.

Cheetah Mk1, 50,592 psi, 3654 fps.

22-250 Rem, 50,585 psi, 3549 fps.

You’re right again. There are no standards for the overbore Cheetahs. 50+ K may not be a reasonable pressure but that is what I used.

quote:

Originally posted by MickinColo:

For the Cheetah and a 22-250 to be compared we need to use a powder that works in the 22-250 and the Cheetah. .

Mick - I appreciate your two posts comparing the .22-250 and the Cheetah. Very infornmative.

Just out of curiosity, how do they compare when you DON'T use the same powder in both?

Supposedly, one of the advantages of the Cheetah is that a shooter can use EVEN MORE of a SLOWER BURNING POWDER, thus maintaining the same pressure for an even longer time than if he just uses a slightly heavier charge of the same powder.

Does QuickLoad confirm that?

AC,

I really haven’t thought much about the Cheetahs until Budiceale posted this thread. The first thing that struck me was how low its maximum pressure was set. 50,763 psi is pretty low compared to other large volume 22 cases. The Swift is set at 62,366 psi (47 grains water volume). Even the incredibly overbore 220 Howell (basically a necked down 270 Win) has a P max of 58,000 psi (62 grains water).

I’ll run some numbers using a 52 grain Sierra MK Hp at P max.

The numbers are case fill %, charge in grains, fps.

Norma MRP 101.0, 50.7, 3870

Alliant Reloder-25 108.6, 51.9, 3864

Somchem S365 97.1, 46.4, 3845

Hodgdon Retumbo 115.3, 55.7, 3836

Alliant Reloder-22 102.8, 50.0, 3829

Alliant Reloder-17 87.3, 44.0, 3829

These are powders from QL’s top 10 picks. Very respectable velocities but no more than a Swift can produce without going all the way to its P max and without a compressed load. (I don’t think 55 grains of Retumbo will fit in a Cheetah Case but I threw it in the mix anyway)

The Cheetah has a reputation of being a 4,000 fps round.

The numbers are case fill %, charge weight, fps, psi

IMR 4198 88.3, 38.1, 4000, 71,274

Somchem S385 105.8, 51.4, 4000, 63,157

Hodgdon H322 87.1, 40.6, 4000, 65,031

Alliant Reloder-22 106.8, 51.9, 4000, 58,316

Norma MRP 103.9, 52.1, 4000, 56,337

The Cheetah can’t get to 4000 fps without exceeding it’s P max.

On a slightly different note if u wanna get those big necks down fast with no other case changes make yourself up one of these-- the late great Blaine Eddy's neck reducing plate. Chuck the case up in a shellholder and run it into a drill press--add baby oil and voila--

I have been shooting a 224TTH(little more case capacity than yours) for about 10 years. I shoot 69Gr MK with RL19 at 3575fps and a 70gr Barnes X for deer at 3740fps. My gun is a 26"brl with 1/9 twist. A buddy shoots a 224TTH with 53gr SMK using 50.2gr of RL19 and gets in the low 3900fps range. His gun is a 1-14 twist 26".

I THINK that the newest hornady reloading manual might have some data in it for your gun. It is the first manual that had info for the 224TTH that is published by a large ammunition company. It has a 68gr load with RL19 and I am within this range of their manual. WHen we started loading the 224TTH there was NO data published by either powder OR bullet manufacturers. We just used 220swift data and worked up and watched for high pressure signs.

later
224TTH

Bet the new Hornady 53 V-Max oughtta' give some good downrange peformance as well claiming a BC of ~.3.

There was a good article in "The Varmint Hunter" on the CHeeta.
I'll look and see if I can find it. It almost seems like the Nov/2010 issue.

The auther realy got his to preform with some of the newer powder.

Hal

I deleted a couple of my above posts with graphics to make room for this post.

Hal,

I believe the man got good performance out of the Cheetah. When I said “interesting cartridges but not real practicable” (practical if you like ) I refer to the fact that the original Cheetahs are based on the 308 BR case. The original 308 BR not only has a small primer pocket but it’s also thin skinned.

Quickload has a sister program called Quickdesign. It’s a cartridge / chamber design program. I asked QD to transform a standard 308 Winchester case down to the Cheetah MK1 dimensions so QL could import the information and analyze it. The new cartridge performs well and with a number of common powders.

Here is one example from QL.

I forgot to change the barrel length from 23” to 26”. At 26” velocity is 4050 fps.

I have never had a Cheetah, but I do have a bit of experience with a 22/243 Middlested. That said, there is enough "gain" between it and the 22/250 to make a significant difference in the field- add at least 50 yards to the dead on hold with the same bullet. The heavier the bullet, the more the gain. 45-46grs of 760win & a 50-55gr usually yields between 3950-4100 from a 14 twist, 26" barrel. I have brass that has been fired 18 times with 45gr and a 52gr Sierra HPBT. Speed up the twist rate to a 9 or 10 and a 69gr Sierra will exit from 3650- 3750 from a 26" tube. We have gone faster, but brass life becomes short, which means of course the load is too hot. It is one of the best rounds for the pursuit of coyotes a shooter can own. Barrel life is a couple of thousand rounds, depending on the brand. However, without some self control, a high rate of fire and not allowing the barrel to cool, a new barrel can be pretty used up less than a thousand. Load your Cheetah with 60gr Noslers, soot a few deer every year and the barrel will last your lifetime.

Just how would the .22Cheeta hold out against the .22-250Ackley Imp?.

quote:

Originally posted by jens poulsen:
Just how would the .22Cheeta hold out against the .22-250Ackley Imp?.

Quickload is a program that gives hypothetical predictions. As I’ve said many times over the years it’s not gods gift to reloading. It gives an experienced reloader ideas but no tested answers. Some predictions can be dangerous.

With that said, let us see what QL predicts. What bullet make/weight, and powder would you like to test?

PS, the Cheetah wins with case volume alone. Not by much but it's the winner just the same.

Loaded to equal pressure the Cheeta will probably give you about 50fps more than the 22-250AI. A 224Clark or 224TTH will give another 50 or so. With say a 52gr as you use heavier bullets the larger capacity cases will pull further ahead. If I was going to make a life of 70-=80gr bullets I'd look to the 7x57(6mm) based case and a longer action to seat the bullet out. I seriously doubt that anything or any distance you would normally shoot any of these 4 you wouldn't be able to tell the difference.

Guys.
Jim Carmichel & Fred Huntington designed the Cheetah MK1 back in the late 70 using the small primer Remington brass because it was thought to be a little more accurate then using the large primer. It was designed around 50-55 grain bullets using 4064 & 4350 powder at 4100-4200 ft per second. Mainly to be a replacement for the 220 Swift with a slightly heaver bullet. All the Swift high speeds were based on the old 48 gr bullets. It was a real barrel burner. Then the Mk11 came in using the regular 243 case. Neither were designed to shoot the heavy wt bullets. The 224 Clark was designed from the start using the 75-80 grain bullets in a necked down 275 Roberts case.

Even though the 22-250 AI had been developed it was not very popular at that time. With todays powders and bullets there is very little need for either the 22 Cheath or the 224 Clark. All can be done with custom barrels and current calibers. I've played around with all these old 22 wildcats since the mid 60's. Want to try something new go back 40 years or more try the 220 Swift Improved or 220 Weatherby Rocket. Just bring lots of money for more barrels...

Aaron