Ai

Mumptia

Mumptia

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LaCrete, Alberta
Been doing some head scracthing about this new round by Hornaday for the ..30.30.

Asked about it in the city and got weird looks so its not in our neck of the woods yet.

TodB put me onto the AI route which made me scratch deeper.:cool:

Is AIing your rifle as easy as taking to a smith to get re-chambered?

Because the brass gets stretched it shortens the length of the brass? I assume the re-chambering fits the brass when the bolt closes. Stupid question I know, but I'm trying to picture the brass changing shape after being shot in the new chambering.

Does strecthing the brass shorten the life of the brass? (I suppose its a moot point because .30.30 brass is dirt cheap)

Preciate some thoughts
 
Rechambering to an Ackley Improved chamber is a bit more complicated than simply running a reamer into the factory chamber. An Ackley Improved case has a slightly shorter length between the case head and the shoulder/neck junction. For the gunsmith, it involves setting back the barrel a thread so that the Ackley chamber with the shorter headspace can be reamed. You CAN NOT just run an Ackley reamer into a standard chamber, it MUST be set back for proper headspace.

The whole idea of an Ackley Improved case is that it is larger and therefore has more powder capacity than the standard case. When you initially fire the standard factory-dimension ammo in your improved chamber, the only parts of the case that will be in contact with the chamber are the case head in contact with the bolt face, and the shoulder/neck junction. These two contact points hold the case firmly in place, and the pressure from firing "blows out" or expands the case to conform to the shape of the chamber. The case is now larger, and when you reload it will hold more powder for increased velocity potential.

This does depend on a properly headspaced Ackley chamber, wherein the distance between these two points is actually a few thou (4 or 5 typically) closer together than in a standard case. This makes it a slight crush fit when the cartridge is chambered, holding the case firmly in place for the forming process. If this is properly done there is no need to seat the bullet into the lands as is sometimes recommended.

The overall length of the case is slightly shorter after fireforming, and after that the case stretches very little due to the sharp shoulder. Case life is typically longer with an improved case than with the standard factory tapered case like a 30-30. MUCH less case trimming required as a huge bonus.

Fireforming really IS as simple as firing standard factory loads, or reduced handloads in your rifle. Then you reload the larger case in subsequent firings. I haven’t personally worked with the 30-30 AI, but it would be one of the better cases to improve due to the large amount of case taper. I would expect velocity increases of at least 150 fps.
 
La Crete Alberta!!!!
I'll bet not many know where that is. But I do as I lived for awhile in Paddle Prairie Alberta in the early 80s. My wife taught at the school there and I drove a school bus from Paddle to High Level. I guess you are noticing the days getting a little longer up there by now. That was one of the things that impressed me up there, how little daylight in winter and how long the days were in summer. I shot more than a few geese up there and several big black bears.

I normally live now in Rocky Mtn. Hse. but am presently in Australia for a year.

Robin
 
30WCF AI Imp.

Rick F: But he's talking about a cartridge that headspaces on the rim. Different entirely from one that head spaces on the shoulder where the crush fit is desirable to make it work easily. With a cartridge like the 30 WCF it's more important to have a resize die that matches the improved chamber so you aren't over working the brass.
 
stocker said:
Rick F: But he's talking about a cartridge that headspaces on the rim. Different entirely from one that head spaces on the shoulder where the crush fit is desirable to make it work easily. With a cartridge like the 30 WCF it's more important to have a resize die that matches the improved chamber so you aren't over working the brass.
Click to expand...

Good point. But can't it do both, headspace with the rim and on the shoulder? For good case life, I think it has to.
 
Yes, and once it's fireformed in the chamber it does. After that, you partially resize or just neck size. A 30-30 AI is a fun cartridge, works quiet well (I used to shoot one in a Contender, and have another in the works). Ballistically it makes the old Winchester the rough equivelant of a 300 Savage, and that's not a bad place to be. - dan
 
Thanks Rick,

After that explanation, I'm going to start looking for a smith to help me out:) but not until I see this new .30.30 round by Hornaday;)

This sounds like a fairly cheap way to have a little more down range zap.

He,he, Paddle Praire? Hasn't changed since the eighties and La Crete is still 3hours north of the nearest traffic light.:D
 
dan belisle said:
. A 30-30 AI is a fun cartridge
Click to expand...

It is so. I shot a couple out of a guy's rifle at our club. He must have seen the #### eatin grin on my face and gave me a spent case for whatever reason. :confused: So there it sits on my reloading bench looking at me and taunting me every time I'm there. :D
 
I have had two of them, a Win 94 and a marlin 336. Both were rechambered by Paul Rogan, and both were a piece of cake to work with. Just chamber a standard case and fire.

Both would get over 2600 fps with 150 gr bullets. Surpisingly, the Winchester actually took hotter loads and got slightly more velocity than the Marlin, before extraction started getting sticky.

The problem with both of them was the reamer cut the chamber to the proper specifications, but all the 30-30 brass was way undersize so the fired cases had a very pronounced bulge ahead of the rim.

Ted
 
so the fired cases had a very pronounced bulge ahead of the rim.
Click to expand...

I hate that. Doesn't seem to be the case (pardon the pun) with the piece of brass I have Ted. I'm going to have to quiz the guy on how his rifle was done. If I remember right his father in law gave it to him, a little NEF single shot...
 
Mumptia,

I don't think Paul is doing much gunsmithing any more. IIRC, Boss Hogg had his done by David Henry down your way in Alberta.

No extraction problems with the bulge, but reduced case life and looks terrible. :rolleyes: :mad:

PM coming your way.

Ted
 
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