Wildcat question

[midwesthunter]

OK i know i ask a bunch of questions but how you going to learn right? OK i have read and read threads on here. I am a speed freak but have to be accurate. I was wondering if some one has taken a 7mm RUM and necked it down to a .22 cal? would that push the too fast to get any acuracy out of it? My grandfather was a big wildcater back in the day. But back then it was cheap to do macien work and he had access to a lot of matterials

 

[steve smith]

I doubt that to many have attempted that combination. A 22cal with 100+grains of powder would be way into the area of diminishing returns. In fact It would probably be to far, I'm guessing that it would probably only get something like 200-300 rounds down the tube before rebarreling. Something along the lines of a 22-06 (a 30-06 neck to 22) would probably be as far as you would want to go with a 22 cal. Even that will have a very short barrel life.

 

[BountyHunter]

That is so overbore, I am not sure your barrel would last thru the load development. I would be surprised if you got 400 rounds out of the barrel before it was toast.

PO Ackley in his Vol 2 book talks about a 22/378 Weatherby shooting 105 grains of powder and max velocity was 4600 fps.

In order to keep bullets together at that velocity you would have to go to a 1-14 or 15 twist at least also.

Lot of effort and expense for such a little gain.

BH

 

[jwp475]

The 2 post above nailed it IMHO

 

[midwesthunter]

Thanks guys i should have been a little more spesific. I was wanting to push the heavier .22 bullets over or arounf 4000 fps. Bullets in the 70 grain range. What about necking down to a .243 caliber?

 

[steve smith]

The smallest I've seen the Rum case taken down to is a 25x300RUM, and it's still a real barrel burner. I have a 270x300Rum and only got about 1100 rounds through the barrel before it really lost it's accuracy potential, a 6x7mmRum is probably not going to last 1000 rounds. The 6mm-06 or it's shorter twin the 6mm-284win, is probably as far as someone who's just starting into wildcatting should go. One thing you should remember and keep in mind is that the larger the bore diameter is with respect to the case capacity, the longer it will last. Small calibers with larger case capacities are hot rods, but they don't last that long.

I understand the speed freak thing, I was there once. Just try to remember that being the fastest isn't everything.

Personaly, I'd suggest that you think about a 22cal based off of a 243win case, or maybe an improved version. something like this would allow you to push the heavier bullets whilst prolonging the bore life for a while longer than anything off of the RUM case.

 

[Derek M.]

Thanks guys i should have been a little more spesific. I was wanting to push the heavier .22 bullets over or arounf 4000 fps. Bullets in the 70 grain range. What about necking down to a .243 caliber?

Forget the 243. What you are looking for is the 22-6mm Remington. Get a 27" bbl. You'll be pushing fast but stick to the accuracy department line of thinking. If you're bullets are going faster than 4000fps but you can't hit the target, then what's the point?

Plus, I can't think of ANYTHING wrong with THREE THOUSAND SIX HUNDRED FEET PER SECOND. Can you? You'll save case life, throat life and your accuracy may surprise you.

I love speed too but not at the sake of accuracy. That's why we have better designed bullets with high BCs. I'll take accuracy and known trajectory ANY DAY over velocity, period.

 

[Varmint Hunter]

In my 22-243 AI I would shoot the 75gr A-max @ 3,670 ft/sec. This load was extremely accurate in my heavy varmint rig. Best group was .625" @ 600 yards. (lasered & witnessed)

You could easily exceed 5,000 ft sec if you reduced bullet wight to 30gr. I never bothered with light-weight .224 bullets because the BC was so low.

Plenty of good 75gr - 90gr .224 bullets for the 22-6mm, 22-284, or 22-06 if you really want a longrange .224 based rifle. I'm guessing that there would be no practical advantage to a 22-7mm mag. If there were 120gr .224 bullets and barrels twisted accordingly then the extremely overbored 22-7mm might make a very interesting and entertaining cartridge. However, throat life would be rather limited.

 

[midwesthunter]

HEy Varmit hunter whats the advatntage of the 22-243 AI a 243 wsm? Not sure the balistics of the wsm but have to be close? I have a 6.5-243 haven't messed with it yet. I know a AI improved .223 can get about 150 fps more. I would love to have a gun that could push a 70-75 grain bullet around the upper three grand range and be a laser.

 

[J E Custom]

OK i know i ask a bunch of questions but how you going to learn right? OK i have read and read threads on here. I am a speed freak but have to be accurate. I was wondering if some one has taken a 7mm RUM and necked it down to a .22 cal? would that push the too fast to get any acuracy out of it? My grandfather was a big wildcater back in the day. But back then it was cheap to do macien work and he had access to a lot of matterials

I would recomend the .223 WSSM or the .243 WSSM. Because these are factory chamberings
and they are very fast.

I built a .223 WSSM a while back and did some testing and due to sholder surgery have not
completed all of my testing but hope to soon.

So far I have loaded the 62gr bullets to 3915 ft/sec with no pressure signs and a standard deviation of 0006 ft/sec.

My goal is to push the 40gr Blistic tip to over 4400ft/sec in a 1 in 15 twist 3 grove Lilja.

You can buy a rifle already chamberd in these rounds if you don't want a custom but you
probably cant reach these velocitys.

These days there are so many hot cartriges available a wild cat is not nessary unless you
just want one.

J E CUSTOM

 

[mike33]

In my 22-243 AI I would shoot the 75gr A-max @ 3,670 ft/sec. This load was extremely accurate in my heavy varmint rig. Best group was .625" @ 600 yards. (lasered & witnessed)

You could easily exceed 5,000 ft sec if you reduced bullet wight to 30gr. I never bothered with light-weight .224 bullets because the BC was so low.

Plenty of good 75gr - 90gr .224 bullets for the 22-6mm, 22-284, or 22-06 if you really want a longrange .224 based rifle. I'm guessing that there would be no practical advantage to a 22-7mm mag. If there were 120gr .224 bullets and barrels twisted accordingly then the extremely overbored 22-7mm might make a very interesting and entertaining cartridge. However, throat life would be rather limited.

Isnt the 243 necked to 22 called the Cheetah?
mike

 

[roughneck]

Yes, the 22 cheetah. I actually have one. It was made by my grandfather, and i'm sure it still shoots, but i won't use it. He used to shoot five shots in a 30 caliber hole with it. still have some of his targets.

TX