Question about Ackley Improved

[WItoOR6637]

Anyone looking to sell one of their 280ai's? I've got all the components piece mealed together and no one to dance with yet. Gonna have one built in a short while if I can't find what I'm after. Pm me if you have something.
Not trying highjacking in the least 280ai is a small group. Ton of questions answered above. Thank you for that.

 

[Hugnot]

RE: the .22 L-B-E-Splitten Boomer:

Only about 60 years olde, possibly they "antiqued" the paper to provide sort of a mellow appearance to encourage discussion & progression - like new propellants. Possibly an extra slow burning double base powder might get another 100-200 fps.

The shoulder needs to be sharpened up to 40*, looks like its only 30*, that and some H869 might get 75-150 fps more. COW FF would be messy.

Shooting a 55 gr. out of my 10 twist, 26", 6mm AI using RL 16, I can chrony real close to 4,000 and that is in line with Sierra published data. RL16, a new, double base extruded powder fills the case about 95% for that load. I would guess pressures are 62-63K psi. I don't use that load, preferring 87 VMax.
bullets.

The 6mm AI sort of looks, "badass" but it won't feed well in my FN Mauser rifle, real olde design like 122 years.

 

[GLTaylor]

On another note, the gentleman I bought my rig from, actually fire formed his brass in a separate barrel. When I got it,it only had three hundred actual bullets through the bore. My bore, and throat are in excellent condition. It really likes mono bullets, but shoots Fowler match bullets very nicely. Also likes Sierra Blitz Kings also. Groundhogs, not so much!

Agree. I had my 22-250 AI rebarreled. Kept the old barrel and had it rechambered to match the new barrel. It's a switchlug, so I screw the old bbl on for initial fireforming. Saves the new 1:8 barrel for more important things!

 

[hunter67wa]

P.O Ackley's book was written a long time ago, with the new powders available today this doesn't hold true anymore

Actually, I said that to show some of the differences with some more than others. IF things are to get better it will be across the board. Linear. Someone should test all of these calibers that are improved to see what we have gained.

 

[Lonewolf74]

Ok guy's this thread as well as quite a bit of research and reading has lead me to going with an improved version for my 338 Norma build.

The reamer I specked out for the 300 grain Berger's. The question I have is regarding bullets for fire forming, I was planning to buy some of the cheapest bullets I could find to form brass and do break in. What got me thinking is all the cheaper bullets are lighter and shorter design. Sooo is it necessary or recommended to use some "jam" while fire forming?

I have some Berger 250's that I played around with while making dummy rounds and if my calculations are correct the closest I'll get to the lands while still having enough bullet in the neck will be about .060 off the lands. I think that will mean anything like the 225 Hornady will be quite a ways from the lands.

The reamer and go gauge is specked -.004 which I believe is typical AI and should give me a little "crush" on the neck, shoulder junction but is it still recommended to have some "jam" on the bullet?

Thank you for any help/advice
Joshua

 

[FEENIX]

Ok guy's this thread as well as quite a bit of research and reading has lead me to going with an improved version for my 338 Norma build.

The reamer I specked out for the 300 grain Berger's. The question I have is regarding bullets for fire forming, I was planning to buy some of the cheapest bullets I could find to form brass and do break in. What got me thinking is all the cheaper bullets are lighter and shorter design. Sooo is it necessary or recommended to use some "jam" while fire forming?

I have some Berger 250's that I played around with while making dummy rounds and if my calculations are correct the closest I'll get to the lands while still having enough bullet in the neck will be about .060 off the lands. I think that will mean anything like the 225 Hornady will be quite a ways from the lands.

The reamer and go gauge is specked -.004 which I believe is typical AI and should give me a little "crush" on the neck, shoulder junction but is it still recommended to have some "jam" on the bullet?

Thank you for any help/advice
Joshua

With respect to the OP, you might want to consider starting your own thread, so responses are geared specifically towards your current goal/situation. There are a few .338 NMI owners here that can chime in and help you. Good luck!

 

[7stw]

Ok guy's this thread as well as quite a bit of research and reading has lead me to going with an improved version for my 338 Norma build.

The reamer I specked out for the 300 grain Berger's. The question I have is regarding bullets for fire forming, I was planning to buy some of the cheapest bullets I could find to form brass and do break in. What got me thinking is all the cheaper bullets are lighter and shorter design. Sooo is it necessary or recommended to use some "jam" while fire forming?

I have some Berger 250's that I played around with while making dummy rounds and if my calculations are correct the closest I'll get to the lands while still having enough bullet in the neck will be about .060 off the lands. I think that will mean anything like the 225 Hornady will be quite a ways from the lands.

The reamer and go gauge is specked -.004 which I believe is typical AI and should give me a little "crush" on the neck, shoulder junction but is it still recommended to have some "jam" on the bullet?

Thank you for any help/advice
Joshua

If, you are fireforming with a bullet, it's better, to be in the throat, but, if when you resize you brass, if you leave a little dimple at the base of the neck, it creates a false shoulder, and keeps the base firmly against bolt when firing. That's critical, otherwise you'll have excessive headspace. If you have a lot of free bore, that may be best option.

 

[Lonewolf74]

With respect to the OP, you might want to consider starting your own thread, so responses are geared specifically towards your current goal/situation. There are a few .338 NMI owners here that can chime in and help you. Good luck!

Your right Feenix I just thought this was well related to the thread but it is specific to my situation.

 

[FEENIX]

Your right Feenix I just thought this was well related to the thread but it is specific to my situation.

It is, but when people do a search/query later, whatever information shared here "might" not pop up because it is buried too deeply. As noted, it also maximizes responses specific to .338 NMI. When the post is titled accordingly, it will have more results, but that's just me.

 

[Saskquatch6]

What level of improved performance do you srr in the 6.5x55ai over the good ol' Swede?

Haven't got it from the smith yet. I really do an ackley for the brass and take whatever I get for gain.
My 223ai is pushing a 53gr vmax at 3394 fps out of a 17" tube, but no more trimming and stupid accurate also with FF loads also.

MooseChaos/hunter67wa - been on the road and just got back home to look up my records for 6.5x55 vs 6.5x55AI. Average grains of water increase (Lapua to Lapua fire-formed AI) was 5.0 gr which is an increase of about 8.5%. As a qualifier, I load for accuracy and fairly conservatively- my safe and proven 6.5x55 load with 130gr Sierra GameChanger or Nosler AB gives velocity of 2750 fps (23" bbl). I worked up my load for 6.5x55AI thinking the max equivalent AI load would be approximately 2750 +8.5% = 2984 fps (about +200 fps) with same bullets. I started with max standard 6.5x55 SE loads and worked up. I found an accuracy/velocity node at 2925 fps and stopped there with no indications of pressure. I've been shooting this load for about 15 years and it's performance has literally been outstanding. In a strong modern action I'm sure you could safely get these numbers or better with 140-145 gr bullets. I just haven't pushed the envelope as I use this rifle for coyote, antelope and deer. While I'm sure it would do the job on bigger game, elk/moose, I prefer my 300 WSM for that. These loads still use RL22 which was the powder of choice at the time I first started with this and I'm comfortable with the performance for my use. However, given some of the new powders esp RL26, I think you could get outstanding performance from this AI with some of the newer and heavier 6.5 bullets. JME - hope it's helpful.

 

[MooseChaos]

I like that! I have a partial build - 6.5 bore 26.5" barrel on a M98 action with an ultralight classic German pattern Schnabel stock. It's short-chambered 6.5x55 and I've been considering the A.I. version. I think I'll go ahead and finish it that way now! Thanks again!!!

 

[hunter67wa]

Just got my 250ai from smith yesterday!

 

[GauleyRidge]

Anyone looking to sell one of their 280ai's? I've got all the components piece mealed together and no one to dance with yet. Gonna have one built in a short while if I can't find what I'm after. Pm me if you have something.
Not trying highjacking in the least 280ai is a small group. Ton of questions answered above. Thank you for that.

PM sent...I have a Christensen Ridgeline I may be convinced to part with.

 

[7stw]

Guys, I just came in from fireforming Lapua 30.06 brass, into 25.06ai, using the Cow method as most of us know and have used.
On my first batch, I used a lesser charge of Unique, and occasionally, I came out with semi rounded lower shoulder angle. I merely , but incrementally, raised the charge, and all off this second batch has nice sharp shoulders. I set up my new Lee collet neck die, which I just received for Christmas, and now I'm ready to load some real stuff, and saved on firing 60 bullets down the barrel. A few years ago, I wouldn't even consider an Ackley. And now I find that it's no big deal at all.
The point I'm making is that during the COW , process, you may find the need to raise your charge, or to put more, or less filler in, etc. Its all good.