It's a fun cartridge. Magic kinda...in goes a slope shouldered thutty thutty case, out comes a racing full bodied, short necked 'correct' looking case.
I did it to my Handi Rifle about 15 years ago [don't remember really]. I would recommend doing it in a lathe if you can although it can be done by hand as well if careful [taking care to blow out chips with each small amount of cutting].
I've built several Ackley Improved rifles as well as switch barrel bolt rifles. Your question is one that comes up a lot. I would say yes it's worth it..because: you want to 'try it'. It's not a bad modification to an inexpensive rifle, and if done right it is an enjoyable round. I shot several deer with my Handi in 30/30AI as well as other barrels I had NEF fit to it. My 30/30AI barrel would touch the first 3 shots at 100 yards, and start slinging the 4th and 5th shots 3" and 7" out in the same pattern for every 5 shot group I shot if I shot with the same cadence between shots. This is totally acceptable as the barrel fit was tight. A tightly fitted Handi barrel has no where 'to go' if it heats up and expands when shot so it was not a suprise to me to see 4th and next shots fly out of the group. First 3 under an inch is TOTALLY acceptable, might say DESIRABLE for a deer hunter. A 10 minute cool down after a group was fired would bring it's capability back to 'first 3 touching'. Actually this had nothing to do with it being an Ackley, it did the same when it was a standard chamber.....it's just a quirk of a tightly fitted Handi barrel, and not a bad thing.
I think one reason to do your 30/30AI is because you are curious, and 'not' doing it may always leave you wondering. Actual advantages to do the AI is longer case life for one, but who wears out 30/30 brass anyway? If your a gun range scrounger, you probably can find and pickup all the once fired 30/30 cases you will EVER need if you visit the range the 2 weeks before gun season opener in your area.
Dies? Now you can buy inexpensive LEE dies in 30/30AI. When I did mine the AI dies were a bit high. I used a .308 Winchester full length die to NECK size my 30/30AI cases, usually just a caliber's length down the neck. I used the standard 30/30 Win seater die to seat bullets. I did FL size my pickup cases in the standard 30/30 Win FL die to start with. After several loadings I still did not need to FL size my 30/30 Ackley fired cases. I had so many once fired 30/30 Win cases that if I did find some AI cases needing to be full length sized I could just start over with once fired 30/30 cases that had been run through a standard 30/30 FL die. I do have a 30/30 Ack Imp die set now but aquired them only recently when I had a Contender barrel in 30/30AI for a while.
When and if you cut your chamber to AI, be SURE to give FULL ATTENTION to the rim recess. The 30/30AI reamer I use will cut a tad larger diameter than the factory barrel rim recess in the barrels I have AI'd. This allows you to see the cutting progress so as to not deepen your barrel's rim recess AT ALL. If you do it will increase the headspace the same amount and most factory barrels in 30/30 are already sloppy and about max in dimension. You or your smith do NOT want to cut it any deeper! The rim recess in the barrel is used for only the first firing as headspace control. All reloads after the first fireforming will be headspaced on the shoulder, or should be. You can 'depend' on the rim to hold the case but a chamber shoulder is the best way to 'hold' the case in place. It will allow longer case life. I neck size only - you don't want to push the shoulder back at all. If you get fired cases that don't want to 'easily' rechamber then you probably are loading to too high a pressure - not a good or safe practise.
I have to agree with the posts that say if you want a 'hot' 30/30, AI or standard, it can be done fairly easily......by buying a .308 Win! Ha!
Just yesterday I gave a box of .375 Win brass away to a friend with a Marlin .375 Win. I had necked them down to 30/30 to fireform for my [long ago sold] 30/30AI Handi rifle. I was thinking a 50,000 psi design case would allow me to 'bump up' some pressures and velocity. I reconsidered and decided the 30/30 should still be a 30/30 and does not need any spinach [as in Popeye] to boost it up.
I've gotten to like the 30/30 Winchester in standard form. You can load it to almost what you could with it it in Ackley Improved form. Longer case life would be nice with an Ackley Improved, buy hey!....we walk all over fired left behind 30/30 Win cases at the ranges anyway!
So..hmmmm...what you gonna do?!
