How do YOU fire form Ackley Cartridges?

[MontanaJack]

My first and only Ackley Improved firearm is a 22-250AI. After using several "gunsmiths" that turned out to be hacks, I got established with Young's Gunsmithing located near Great Falls, MT. Dave Young has done incredible work for me, cleaning up messes made by the hacks. The 22-250AI was my first Build with Dave. He provided step by step guidance to help me through this experience. My 22-250AI shoots lights out with a load provided by Dave. At his direction, I fire-formed brass by using factory loaded ammunition. Hopefully, you have access to an experienced professional to guide you through the process. Blogs are great to learn of experiences from a broad field of practitioners. However, take what you read with a grain of salt, and take information gathered from blogs into conversation with your professional gunsmith.

I also have personal experience producing brass for 30 Herrett, 6.5 Gibbs, 270 Gibbs, 30 Gibbs, 8mm Gibbs, and 300 Blackout. The processes for making brass for each of these cartridges is unique and radically different from the process for Ackley Improved cartridges. For these cartridges, I was guided by reputable people with hands on experience.

The Gibbs wildcats produced by Rocky Gibbs 70 years ago utilized oil forming hydraulic dies supplied by Gibbs when he did the machining to modify the firearm. That hydraulic process was followed by fire-forming the hydraulically formed cased to produce the final case. I inherited the 270 Gibbs, the Gibbs dies, and the experience producing cases from my father who worked directly with Rocky Gibbs.

In my old age, my new build utilize SAAMI spec cartridges with commercially available brass. None of my heirs are into wildcats and all the extra work that goes into using them. So, my wildcats probably won't survive into the next generation. My current build, a 6.5 RPM, started out to be a 6.5-06AI. However, the 6.5 RPM is very similar and the grandson that will inherit the rifle will be able to buy commercially available ammunition.

Wildcatting is fun. I learned a lot by doing it. Good luck with your new AI.

 

[L.Sherm]

That's what shooting a factory loaded parent cartridge is. Again, do not over complicate it unnecessarily.

Unfortunately Feenix this is what happens, stuff gets lost in the weeds and over thinking.

 

[greenejc]

What chamber are you having Ackley improved? Kinda hard to give advice without knowing what cartridge you are planning on forming. You are dealing with an explosion 4" from your face so its not a "one size fits most" situation.

In a properly set up Ackley improved chamber your standard chamber go-gage becomes your no-go gage. An ackley improved chamber should be about .006" shorter than a standard chamber so regular factory ammo should have a bit of a "crush fit" of about .004" between the neck shoulder junction and the bolt face. If your chamber is too long to get a good stiff bolt close on factory ammo then I would neck up 2 caliber sizes then neck back down and use the false shoulder method. I fire form and hunt with the minimum starting load for standard 25-06 Rem in my 25-06AI chamber with new norma 270win brass as the parent case.

Forming 25-06AI for 25-06rem will leave you with short necks that will stay short after multiple firings. Most standard to Ackley conversions using the standard parent case will be this way.

I've used cheap coffee "smells better than burnt COW" and 12% fill of pistol powder in a 223ai before. But after learning how to do the false shoulder method I create an amazingly accurate fire forming load that is great on game out to 200yds. The only difference between the FF load and the fully formed load is the formed load holds more powder and is about 175fps faster.

Some guys jam bullets into the lands to get proper contact between the case head and bolt face but that method personally freaks me out.

@Coyote Shadow Tracker is right about this being discussed multiple times on here. Heck I started a thread not long ago myself.

Good luck and go slow!!

I use the .270 brass for my standard 25-06 and trim to length, but I do size it for a crush fit in my Ruger No.1. It gives me extremely accurate loads, and my brass is range pick-up brass, so its free. My gunsmith is William Trotter, who retired from the Whittington Center a few years ago and moved to Colorado, near my house. I know he could do an AI for me because he has made a number of them. I may get him to re-chamber a couple of 35 Whelens for me next year. He made one of the Whelens for me about two years ago using an ER Shaw 1 in 14 twist 26 inch barrel on a Remington action, and it shoots inside an inch at 100 yards with good handloads. He also matched the chamber dimensions on it to my factory Remington CDL in 35 Whelen, so I only have to neck size and the loads fit both rifles. But if I do one, I have to do both.

 

[greenejc]

My first and only Ackley Improved firearm is a 22-250AI. After using several "gunsmiths" that turned out to be hacks, I got established with Young's Gunsmithing located near Great Falls, MT. Dave Young has done incredible work for me, cleaning up messes made by the hacks. The 22-250AI was my first Build with Dave. He provided step by step guidance to help me through this experience. My 22-250AI shoots lights out with a load provided by Dave. At his direction, I fire-formed brass by using factory loaded ammunition. Hopefully, you have access to an experienced professional to guide you through the process. Blogs are great to learn of experiences from a broad field of practitioners. However, take what you read with a grain of salt, and take information gathered from blogs into conversation with your professional gunsmith.

I also have personal experience producing brass for 30 Herrett, 6.5 Gibbs, 270 Gibbs, 30 Gibbs, 8mm Gibbs, and 300 Blackout. The processes for making brass for each of these cartridges is unique and radically different from the process for Ackley Improved cartridges. For these cartridges, I was guided by reputable people with hands on experience.

The Gibbs wildcats produced by Rocky Gibbs 70 years ago utilized oil forming hydraulic dies supplied by Gibbs when he did the machining to modify the firearm. That hydraulic process was followed by fire-forming the hydraulically formed cased to produce the final case. I inherited the 270 Gibbs, the Gibbs dies, and the experience producing cases from my father who worked directly with Rocky Gibbs.

In my old age, my new build utilize SAAMI spec cartridges with commercially available brass. None of my heirs are into wildcats and all the extra work that goes into using them. So, my wildcats probably won't survive into the next generation. My current build, a 6.5 RPM, started out to be a 6.5-06AI. However, the 6.5 RPM is very similar and the grandson that will inherit the rifle will be able to buy commercially available ammunition.

Wildcatting is fun. I learned a lot by doing it. Good luck with your new AI.

I used to know a gentleman in Ralls Texas that shot a .270 Gibbs. I think he used the false Shoulder method for fire-forming his brass. That was back in 1969. He used a 26" barrel. It had lots of reach and was very accurate for the time. How close is the .30 Gibbs to the .308 Hawk/Scovill?

 

[DUCKMAN11]

I used to know a gentleman in Ralls Texas that shot a .270 Gibbs. I think he used the false Shoulder method for fire-forming his brass. That was back in 1969. He used a 26" barrel. It had lots of reach and was very accurate for the time. How close is the .30 Gibbs to the .308 Hawk/Scovill?

30 Gibbs is 30-06 based

 

[del2les]

I used to know a gentleman in Ralls Texas that shot a .270 Gibbs. I think he used the false Shoulder method for fire-forming his brass. That was back in 1969. He used a 26" barrel. It had lots of reach and was very accurate for the time. How close is the .30 Gibbs to the .308 Hawk/Scovill?

When I owned a 270 Gibbs, I used the false shoulder method as well. Either partial necked down a 280 case or often necked up 270 brass to 280 or 30 cal then partial neck sized back down for fire forming.

 

[greenejc]

I am assuming you are referring to your .270 AI project. Ackleys are designed to be fired with the parent case/cartridge. As I previously noted in my PM, I developed an accuracy load for .270 Win and .270 AI. I only have one AI, but I have some wildcats.

View attachment 451877
.270 Win with 150 NABs and .270 AI with 175 Matrix

I have pre-formed brass using the COW method (I use cotton balls) and hydraulic forming dies. The recipe might depend on the powder to use. On my .30 Gibbs, I used WST with roughly 15-20 percent of a full load. You might have to adjust accordingly. I only did the COW method because it is too much of a jump from the parent case to .30 Gibbs.


View attachment 451860
View attachment 451861
View attachment 451862
From L-R
1 - .35 Whelen virgin brass
2 - After running through .338 WM and .30-06 sizing dies to establish a false neck
3 - After running through .30 Gibbs sizing die
4 - After COW method with 11g of WST
5 - .30-06 Virgin brass

This is with my .338 Thor using hydraulic forming die.

From L-R
1 - .338 Norma Magnum virgin brass (Lapua)
2 - After running through the hydraulic forming die, and sizing die
3 - After fire-forming off the rifle's chamber with 250g bullet and 91.5g of Magpro

Pre-forming the brass depends highly on what type of work you are willing and able to do. In either case, it is best to do load development when the brass has been fire-formed off your rifle's chamber. Good luck

What velocities are you getting from your .30 Gibbs and from the .338? That's nice looking brass, and a nice demonstration of the fire-forming stages for each cartridge. How much are the forming dies and where do you get them?

 

[hankle]

Just read that your round will be a .270AI. You should get around 100fps increase with safe loads in it in a 24" barrel. Good luck. And the reason your 7mm Rem Mag stretches is that most all the rifle manufacturers headspace that round on the belt instead of the shoulder, and then they make the chamber too long. My 300WinMags are headspaced on the shoulder, which gives me about twice the brass life of the 7 mag.

I'm excited about the 270AI, the people that have it seem to love it. I bump my shoulders back .002 on the 7mm mag after firing.

 

[Ruger4570]

I load a medium load ,with any bullets . Drop in chamber close bolt pull trigger , instant case.

 

[greenejc]

30 Gibbs is 30-06 based

So is the Hawk, but after several minutes of searching, I finally found it, and I named it wrong. It is the .300 Hawk . Its pretty similar to the .30 Gibbs. All the Hawk and Scovill lines are based on the .280 Rem necked up or down with the shoulder moved forward. I think they also change the angle of the shoulder slightly and take some of the taper out of the case , but I'm not sure about that. I can't find the cartridge dimension data posted anywhere anymore. I know that Z-Hat custom used to chamber them.

 

[greenejc]

I load a medium load ,with any bullets . Drop in chamber close bolt pull trigger , instant case.

That's what I did with my 8mm-06 improved, except for necking it up to .323.

 

[greenejc]

I'm excited about the 270AI, the people that have it seem to love it. I bump my shoulders back .002 on the 7mm mag after firing.

For my 300 WM, I just size it to fit in both rifles, and check the sized brass for a tight fit by chambering it in the rifles. I don't worry about bumping the shoulder. If the brass chambers with just a slightly tight fit in both rifles then it is sized right. It might not fit someone else's 300WM, but if it fits both of mine, I'm good. You'll like the .270 AI. It'll give you about 100 to 150fps increase in velocities, depending on bullet weight and barrel length. Are you going with a 24" or a 26" barrel, and are you going with a fast twist rate for the heavier bullets, or the standard twist?

 

[hankle]

For my 300 WM, I just size it to fit in both rifles, and check the sized brass for a tight fit by chambering it in the rifles. I don't worry about bumping the shoulder. If the brass chambers with just a slightly tight fit in both rifles then it is sized right. It might not fit someone else's 300WM, but if it fits both of mine, I'm good. You'll like the .270 AI. It'll give you about 100 to 150fps increase in velocities, depending on bullet weight and barrel length. Are you going with a 24" or a 26" barrel, and are you going with a fast twist rate for the heavier bullets, or the standard twist?

Douglas 26" 1-8 twist. I'm planning to play around up to 170gr.

 

[milo-2]

How many guys do load development on new barrels?
What better time to form brass than to get rounds on a barrel, shoot some kind of varment with forming loads.

I do, I guess I put enough pcs of new brass in service that I need too. One rebarrels an action, you have an idea just where in the speed spectrum that you want to be at, so if you have a load in 30-40 rds, you should be able to figure out how much under your desired speed you need to be, and have the load hold. The barrels made these last 6-7 yrs are very predictable.
I also develop on new brass and honestly, I don't buy the myth that once fired brass is more accurate. Matter of fact on this subject, sometimes, it becomes almost impossible to duplicate the actual neck tension of some Lapua brand brass and the first firing may be the best it has to offer.