.22-6 mm Ackley Improved, Half-Mile .22?

[TCTRAV]

Hey guys,

I just received my new American Rifleman magazine and read the article titled Half-Mile .22's.  I have a few questions about this cartridge if anyone can help.  I plan on building a Encore based rifle for long range shooting at prarie dogs and coyotes.  I would like to use a rimmed case if possible for this single shot.  My question is, can I buy and use 6.5x57R cases from RWS and neck these down using the same dies for forming and loading.  I don't think it would be a problem but am not sure.  Any help would be appreciated.

Thanks

Trav

[iiranger]

The best source for this sort of question is the die makers. Ch4d.com. Redding. Hornady. Huntington Die Specialties. (RCBS custom shop). They can tell you the possible and the costs... This is not for the faint of heart or thin of wallet....

The 6mm  (Remington probably) was necked down from a .257 Roberts (Remington) which was necked down from the 7x57 Mauser... AND, per Mr. Ackley, the .257 Ackley Imp has the exact same powder capacity as the .25 Krag Imp (full length). [And you might care to note the similarity of the .303 Brit Case to the Krag case... Mr. Epps worked much with the .303 in Canada improving it and offerring different calibers and I think his sons still run the gun shop, link thru at 303british.com]

As Mr. Ackley put it, the long heavy, arrow like bullets retain velocity well, but with that tiny base to push on, getting them up to speed is more of a problem, i.e. barrel wear. Wind resistance is a balance between ballisitic efficiency and time in flight...

What you propose, using the ??x57R cases, should work except you will need the "R" shell holder and want to consider the head space carefully. Not all shell holders match all dies close enough. BEWARE. No big deal if you manage it. HAPPY HOLIDAYS. LUCK. Happy trails.

[onesonek]

Hi Trav,
I like the 57R case a lot!!!!
The 22-6mm rem AI would be a good one.  What you want will work as far as brass is concerned. But you're necking down .040" and it's been my experience without a step in between, the 22-6mmAI sizer will wrinkle a lot of your cases. Take the 6.5R case down with a 6mm rem sizer die first, and you won't lose many with the 22 AI die. It's a little more expense at start up, but will save you in the long run. The sharper shoulder of the AI just don't flow as well when going down much more than .025-.030"
Hope this helped ya
Dave 

P.S.  sent you a PM Trav

[jedman]

I have some new RWS 7 x 57 R cases that I am necking down to .270 cal. and they have very thick necks .020 .
The RWS brass is very nice quality and I think the 6.5 version will work for you but you will have to trim ( thin ) the necks to get them to chamber and fire form to get the new shoulder angle.     Jedman

[onesonek]

This is true Jedman, chances are Trav will have to turn the necks. And likely have to anneal when going down to .22 caliber. He will get better case life. I use 7x57R Norma brass for the 6.5 -257Rob. AI rimmed.
They start out with a neck wall thickness avg. of .015", but thicken to .025". These I dont turn these, I leave the thickness situation to my gunsmith. Well I turn just just enough to make them consistant, I do that for alot of rounds. But on the 6x57R, the neck gets close to .035". Those I turn, otherwise they tend to split quicker and require more annealing.
It's good point brought up, which I neglected to mention. Thanks!


Dave

[TCTRAV]

Thanks for the responses guys.  I just thought it looked like a interesting cartridge.  I don't have any of the components yet but this one will definately be on my to do list.  I find getting funds together is always more difficult than the technical stuff anyway.  I'll post any progress. 

Thanks again

Trav

[TCTRAV]

Just one more quick question.  Why couldn't a person just use the German 5.6 x 57 or 5.6 x 57R and improve it?  RWS makes brass and loaded ammo.  I mean if a case already exists, wouldn't that simplify things a bunch?

Later

Trav

[onesonek]

That would certainly work if you have a source. I just never considered it, because I haven't found it available at my sources.

Dave

[IOWA DON]

Something you might want to think about - By your signature I am assuming you will be using a Thompson-Center, probably an Encore. I have some Thompson-Center TCR-87's, which also have break-over actions. They are strong, but flex more than bolt actions so reloading requires full-length resizing. I have no problem with barrel-burner wildcats for hunting. I like their flatter trajectories and shoot few enough rounds while hunting that barrel life is not a concern. However, wildcat case preparation can be a pain. I have barrels for the .220 Weatherby Rocket which is an improved .220 Swift, and for the 6mm-06, which is not an improved cartridge. The .220 Rocket is a super pain. The chamber has a tight neck so outside neck turning is required. Then because it is an improved cartridge one must fireform them. Luckily I found a fireforming load which has a point of impact nearly identical with the finished loads so that I can hunt with them. I would not want to burn out my barrel just to form cases. I go to this trouble and only can reload the cases about 3 times before I have to worry about case separation from case stretching because of the flexible single shot action. The 6mm-06 cases may also only last 3 reloads, but case preparation is easy. I just neck down .25-06 cases. Anyway, the .22-6mm wildcat holds a lot of powder and has real good balistics, and I doubt if the improved version is that much better. However, the work required to shoot the improved version may be a lot more. I seldom use my .220 Rocket anymore because it is so much work. The 6mm-06 ends up being my coyote gun instead. I also have a couple .17 Hornet barrels for TCR's. The fireforming is again a pain, but the Hornet cartridges are much smaller and don't seem to flex the TCR actions much, so the cases last a long time and the fireforming effort seems worthwhile. Also, barrel life is so much longer that I don't feel like I am burning up a valuble barrel just making cases. That's all.

[Catfish]

I`m shooting a .22-6mm, but not the AI. To neck down my brass I run the 6mm brass through the seating die and then the sizing die and do not use form dies. My guess is that going from 6.5 down to .22 cal. you would have to have forming dies, but in any case you should order your dies with the barrel so and they will still cost you $ 100 or alittle more. With a long barrel you should be able to push an 80 gn. Berger to 3,475 fps. and at that velocity your bullet will drop 11.3 in. from 875 to 900 yrds. In a 10 mph wind it will drift 51.2 in. at 900 yrds. and if it`s running 10 mph you will need to lead it 610 inches. To get past 400 yrds. with any consistency you will need a real good range finder and a wind speed indicator. You will also have to carry a drop chart so you know what to dial in.