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20-tac
09-03-2010, 09:22 AM
HI my friend is wanting to build a fast twist 220 swift i was wondering if any of you guys have done this.He is going to shoot 75 to 90 grain bullets .I am wondering if he goes with a 1 in7 twist if the 90 grain sierra or 90 grain berger will come a part with the higher vel.of the swift thanks

Eric in NC
09-03-2010, 09:36 AM
Actually the world may come apart if you shoot heavy bullets out of a Swift. It just isn't done.

tammons
09-03-2010, 10:40 AM
1:7 is probably too fast and 1:8 might be too fast too, depending on what sort of FPS he will run.

Go to 6mmBR and do a search on 22x47 lapua.
There is one good thread there on a guy trying to max one out with 90 gr bullets but old, like 2-3 years.

From what I remember......and if correctly......

The guy started off with 1:7 twist and was blowing up 90 gr bullets on a regular basis.

Dropped to 1:8 and still was blowing up a few here and there.

In the end if I remember correctly he though 1:8.5 or 1:9 would be about ideal, but they were running
something like 3400-3600 ++ ??

Supposedly those bullets are so long that he figured they were actually twisting/deforming in the fast twist barrels.

tiny68
09-03-2010, 11:40 AM
A 220 Swift is pretty similar to a 22-250 AI in capacity. So much so that both Sierra and Berger told me to use the 220 Swift tables for my 22-250AI. With my 28" PacNor 1:8 22-250AI, I can shoot the 80 Berger VLD and the 80 SMK with great results. I can not stabilize the 90 SMK in my 1:8. If you thing you must shoot the 90 SMK then a 1:7 or a 1:7.5 is needed. However, a few people suggest that the jacket on the 80 and 90 SMK is too thin for the velocities (rpm) generated with a 220 Swift case capacity. I had never had a 80 SMK come apart and I have drove them to 3400 fps plus. But my PacNor is a button barrel. I do know that a 69 SMK shoots great in my 22-250AI and I drive them to almost 3700 fps. Coyotes don't fair well. It is not a load to save hides with, really big exit hole. Crows make a big puff.... ;D ;D

The reason I choose the 22-250AI over the Swift was brass. There are some premium brass available for the 22-250. Secondly, it was my first Ackley and it just sounded to cool. When I burn the throat of this 22-250AI out, it will be reborn as a 22-6mm (224TTH). Even more case capacity that the Swift. Lonnie Hummel (sp?) has convieced me into building one of these monsters.

Luck, Tim

Hammer
09-03-2010, 10:40 PM
.

The 220 Swift is used with 48 grain bullets which work well with the 14-inch twist.



Would recommend a necked-down 6mm Remington case for heavy 224 bullets.

Lonnie Hummel of Hornady has been playing with this wildcat for 40+ years.

I have for 30+ years.

.

kslefty
09-07-2010, 07:30 PM
I also chose the 22-250 AI over the swift, mine is 27" 8 twist and I shoot the 75gr a-max @ 3400 fps with great results. Brass is my second reason for the 22-250, the main reason is the swift is nearly impossible to make it feed as a repeater in a savage.

Blue Avenger
09-07-2010, 07:47 PM
the main reason is the swift is nearly impossible to make it feed as a repeater in a savage.


I must be a god!!!!!!!!! :)

the AI is faster, just not as classy

Eric in NC
09-07-2010, 08:19 PM
the main reason is the swift is nearly impossible to make it feed as a repeater in a savage.


No probs for me in a Savage or Ruger...