The .220 Meteorite Rifle-Getting Started.

[Wolfram Malukker]

Getting started on building the rifle to match the cartridge I worked up with the help of a few internet friends.

https://i.imgur.com/B1jt8yzh.jpg

The bolt is 0.550" diameter, and the bolt raceway was cut with a wire EDM. I'll try to keep this updated as things get done on this-it's been about a year since I started on this.

[M-Tecs]

Very nice. What materials are you using? Is it pre-hard? If not who are you using to do the heat treat? What is a .220 Meteorite?

[swheeler]

Sounds interesting, .220 Meteorite, wonder how it compares to the 220 Weatherby Rocket?

[Petrol & Powder]

I hear the .220 Meteorite is out of this world... :wink:

[roverboy]

I hear the .220 Meteorite is out of this world... :wink:


Yep, absolutely.

[Wolfram Malukker]

I do my heat treating, as it isn't cost effective to send out single pieces. I built my own furnace and also have the use of the ones at work, as long as I am not bringing a legal firearm in. The material is 4140 steel, hardened to RC 34-35. The bolt is also 4140, but will be roughed out and then hardened to RC 38-40.

The .220 Meteorite is a .357 mag case run into a .221 Fireball die, that has been shortened 0.110" at the base, and the base polished out. I was going to Ackley the case, but would have had to find a set of .221 Ackley Fireball dies...too spendy.

The initial loading is 16.5gr of IMR4198 under a Speer 46gr jacketed flat point hornet bullet.

[roverboy]

What kind of velocities are you expecting with different bullet weights?

[Win94ae]

How cool!

[Wolfram Malukker]

55gr Hornady #2267B


16.5Gr N-120 , 100% density, 44,597 psi, 2655 fps-16" barrel

17.5gr N-120 , 106.8% density, 53,439 psi, 2794 fps-16" barrel 2910 fps 20" barrel

15.5gr IMR4198, 96.3% density, 38,316 psi, 2514 fps 16" barrel

17.5gr IMR4198, 108.7% density, 54,299 psi, 2818 fps 16" barrel.


46gr Speer #1024


17.5gr IMR4198, 104% density, 43,803 psi, 2853 fps 16" barrel.

18.5gr IMR4198, 104% density, 51,801 psi, 3012 fps, 16" barrel.

19.9gr N120, 110.9% density, 54,950 psi, 3074 fps, 16" barrel.

[firefly1957]

Never thought of doing that I have experimented with the .223 Remington run into .256 Winchester mag dies it seems to lose about 5 grains of water in capacity so you should pick up the same with your case.

AA 1680 should be a good powder choice for the 22 Meteor might even get away with H-110 if you are using high pressure loads.

Seems I did not like IMR 4198 under 45 grain bullets in my 10" XP-100 in .221 fireball but I did not make any notes on it?
I did make this note -Bullet Speer 52 gr H.P. powder IMR-4198 16.0 grs @ 2330 f/s 17.0 grs @ 2527 f/s (.221 fireball)

[357Mag]

Wolfram -

Howdy !

Have you thought about trying. “ Blue Dot “ ?


With regards,
357Mag

[Wolfram Malukker]

Haven't even shot the first cartridge yet. I am taking the chamber reamer to work tomorrow to cut the flutes in.

[adcoch1]

Very interested! I got a used custom die set the other day that is basically a 6mm 221 fireball. I ran a 357 case in there and the wheels started turning. Waiting to see yours now...

[Wolfram Malukker]

One of the original cases-the first 10 were 50 thou shorter than the rest, due to forming issues. After adding in a .256 winchester die to the mix, the neck length increased. That's the Hornady #2267B seated to the base of the neck. The revised case forming brings the case mouth up to the cannelure.

https://i.imgur.com/AgLmV2uh.jpg

And a case print:

https://i.imgur.com/1YM7gN5h.jpg

This is the spool for the magazine, although it will need some polishing to operate smoothly. As is, it hangs cases a bit due to the shoulder angle being hugged a bit too tightly. The case feeds fine, but the bolt is a bit stiff until the shoulder pops up out of the spool a bit.

https://i.imgur.com/5O6ADD0h.jpg

https://i.imgur.com/mV72ALZh.jpg

Found a chunk of 4140 for the bolt, it's not as easy as the round, already hardened bit I've got stashed, but it's *just* big enough. And it will sport a one-piece bolt handle, no brazed or threaded connection. I've got a few pieces like this one, so I can screw up once or twice if I have to.

https://i.imgur.com/yn1cIbwh.jpg

More after the truck gets fixed, the lathe tuned up again, and planting season going OK.

[roysha]

Sounds pretty much like a 22 Jet Improved.

[Wolfram Malukker]

It isn't far from it. By using the .221 dies, though, it has a 23* shoulder angle, and all I had to do was chop .110" off the bottom of the dies, and hone the base end of the die a bit to get it to stop shaving brass off the cases. Since I already had a set of .221 dies but no .221 rifle, the cost of creation was just a few hours.

[Wolfram Malukker]

Well, this took a minor setback. I got layed off work today.

Not a major issue on this front, but annoying. Heat treat will be a little slower because I only have the single furnace, so the draw will have to be done after the high-heat steps are done.

It *does* mean I have a lot more time to do things like this, but first I need to fix a few tools, put some time in on the truck, etc.