22-250 vs 22-250 ackley improved
Posted 01 January 2007 - 04:31 PM
Posted 01 January 2007 - 04:45 PM
Thers's not a huge advantage over the factory round as far as velocity goes. 100-200 fps, about like a 220Swift. Not enough for critters to notice. The case design does not stretch like the factory 22-250 and has less bolt thrust. So, less case trimming, longer bolt lug life. More powder, less barrel life.
IMO, there's no reason to go to the Ackley design over the 22-250 unless you were rebarreling anyway, then it's not a bad idea. And when comparing groups with your buddy remember that the Ackley was chambered in a custom barrel, not a factory tube. Another thing to consider is the Ackley may not feed reliably from a magazine.
WAIT!, You say your buddy had a barrel "rechambered"? Unless it was set back (shortened at the breech and rechambered), it's not a true Ackley chamber.
Edited by Red, 01 January 2007 - 04:47 PM.
Posted 01 January 2007 - 05:36 PM
33.5gr IMR 4895
55gr Sierra Blitzking
Fed match large rifle primer
I get 3/4" to 1/2" @ 100 yards. Me velocity is 3600 give or take. If your pushing 40's the Sierra book says 36.8 gr of IMR 4895 is max.
If your after more velocity I'd dump more powder in the case. If your looking for more accuracy you should look twards a new barrel.... ANY time you burn more powder the barrel wears faster.
If your looking for "minute of gopher" the factory tube should be OK. I'd wait untill you wear that barrel out and them look tward AI id your still interested. Just my 2 cents.
Posted 01 January 2007 - 08:56 PM
Posted 02 January 2007 - 05:37 AM
1st) I wanted a fast twist to stabalize heavy high BC bullets. So I needed a custom barrel anyway.
2nd) To see any real advantage to using the heavier bullet, it needed a little more umph to flatten trajectory for longer ranges and achieve 3400 fps at the muzzle with 69-75 grain bullets.
3rd) Trimming brass is no fun.
I've had a very high success rate in firforming brass. It's not a mild load either. 60 grainer @ 3400 fps forms the case the first time and has been quite accurate although they do not have the range the 75's do at the same velocity in the formed Ackley brass.
Posted 02 January 2007 - 12:25 PM
"I have no experience with the ackley improved but a friend just had a t/c encore barrel rechambered in 22-250 A.I."
Very difficult to rechamber an Encore barrel to an AI correctly. Requires a significant amount of work and for me would not be worth it. If I were buying a custom shop barrel and having one made from scratch that would be different....I'd do it. I like my AIs and particularly my 22-250AI. Not a big performance gain, maybe 100 fps but they look cool and like the others have said virtually eliminates case trimming, shoots factory standard ammo and no big deal to load accurately.
Edited by skb2706, 02 January 2007 - 12:27 PM.
Posted 02 January 2007 - 02:16 PM
Posted 02 January 2007 - 04:21 PM
Posted 02 January 2007 - 07:12 PM