250AI (And others-Comparisons of increases vs. Std. round,etc.) good article

[savageboy]

http://shootersforum.com/showthread.htm?t=5813

Hey All, I found this article very interesting and informative. In fact, its the article that made me want a 250AI and 6.5x55 BJAI!

Bob

[outlawkyote]

There are a few nay-sayers but it sounds like they dont have a lot of experience with AI cases. One even went on to quote his opinion of physics but doesnt have the equiptment to prove what he's saying...LOL.

I love the AI cartridges

[dcloco]

Believe both 6.5x55 AI's that I built are from the article he wrote some time back.

With 140's, I am at 3000 fps, with a little room to go, but keep it there for temperature variance.

The 223 AI's are amazing little creatures. You can push 3600 with 55's (I have yet to try Viht powders). Run mine at 3550 with 55's, 3300 with 69's, and 3150 with 75 AMax's....while using a LOT less powder than a 22/250, therefore, less recoil and less heat in the barrel.

The 22/6mm AI's with 75 gr Amax's can go 3950+....and be accurate. Simply splendid splat factor on prairie dogs at extended ranges.

[GaCop]

This posting really has me pumped, can't wait to get my 280 AI barrel from Sinman!

[savageboy]

dcloco- I can post that 6.5x55BJ AI article if someone can tell me how to post a .pdf on this site.

[BillPa]

Here's another one, my 270-08 Improved. Not a true improved cartridge, but a improved version of the wildcat 270-08.

Here's is a chart of my initial load development a few years ago.



Varget, 130 bullets ( Nosler SBs, Sierra PHs)

Like the 250 Imp compared to the 25-06 this one equals the 270 Win performance, but burns roughly 10-15 grains less powder.

The rifle is a Mod 70 SA, 22" 12 Twist LWT barrel, .560" muzzle.

One thing you might notice are the double bars for the 44 and 45 grain loadings, the results of two different lots of Varget.

It's little brother , the 270-08 makes about 2900 +/- with a 130, just slightly less then the 270 Win performance with 43-44 grains of powder.

Not a big performance gain, but another example of less doing the same.

Bill

[dcloco]

dcloco- I can post that 6.5x55BJ AI article if someone can tell me how to post a .pdf on this site.

I don't know how Savage brother...maybe PM one of the admins???

[GaCop]

That was great reading. I'm glad I decided to go with an Ackley Improved 280 barrel for my long range build. I'll be shooting 150, 168 and 175 grain SMK's. Except for the heavy 175, I'm looking at between 150 and 200 fps gain over a standard 280 Rem. I don't have the barrel yet so all the data I'm looking at is for a 26" barrel. My barrel will be 28" so I should see a bit higher gain in velocity putting me even closer to 7mm mag pereformance at 1000 yards.

[outlawkyote]

Good choice, Ive said it all along that the 280 ackley will be ideal for long range. Im thinking about another one someday

[Eric in NC]

My only problem is the author saying the 25-35 and 30-40 aren't being chambered these days!!!

Uberti etc. will hook you up, as will the limited edition "Winchester" or "Browning" repros from those makers (or whoever owns the name now).

While there isn't really any need to do an AI on the Krag for any North American, non-dangerous game at open sight ranges, it certainly does pick up a lot of steam in the AI version (as do the various wildcats based on the 30-40 - 6mm-40, 25-40, etc.

I haven't played with the 25-35 AI but I have an old roller action that may be crying out for that now... Was thinking about a 224 version of the 22 Savage (or the Winchester version) but the 25 cal diameter might be better.