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Discussion Starter · #1 ·
Was the Swift a wildcat or original case design? For some reason I thought it was an '06 wildcat like the .270 and 25-06. Then I saw one, actually the fella gave me the round. He is getting out of his hobby of extreme long range shooting and PD hunting. The 220 round was next to his desk with a bunch of other unusual rounds....I snagged the 220 and asked him what was up with it. He said it was the 220 Swift Improved. You could tell it was an improved. He said 4700fps.


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The original 220 Swift was designed by Winchester in the mid 30's. It's based on the old semi-rimmed 6mm Lee-Navy case. There's probably more than a few "improved" versions-but I doubt they could reach 4,700fps with 40gr bullets. Maybe so with special ultralight projectiles.
 

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The first prototype was a necked down 250-3000 Savage case. But was based on the the Lee Navy case in the end. I agree 4700 sounds a bit high for an improved.
 

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Discussion Starter · #4 ·
He was most likely embellishing to put it nicely. I know the factory round can be loaded up to 4100 but I dont think the Ackley Improved goes that much higher.


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Perf -

Remember: in Ackley's day, 4831 was as about as slow of a powder as there was - and as such the extra capacity of the improved was labeled as over-bore and essentially was unusable... but with today's much slower more stable powders one can actually get a good couple-300 fps more from the larger improved.

The other note: in Ackley #1 he does list a 29gr jacketed 220 swift load: 42gr of i3031, at 4665 fps (but this is probably with a 28 or 30" barrel and at "please bring me the sledgehammer- I need to get the bolt open" pressures).

do shoot straight,
greg
www.gmdr.com

ps. the other point to always remember about ackley's data: most of it was taken with a ballistics pendulum, ie, a +/- 10% device, on a good day (only the very last data from the '60s was taken electronically).
 

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Discussion Starter · #6 ·
gmushial said:
Perf -

Remember: in Ackley's day, 4831 was as about as slow of a powder as there was - and as such the extra capacity of the improved was labeled as over-bore and essentially was unusable... but with today's much slower more stable powders one can actually get a good couple-300 fps more from the larger improved.

The other note: in Ackley #1 he does list a 29gr jacketed 220 swift load: 42gr of i3031, at 4665 fps (but this is probably with a 28 or 30" barrel and at "please bring me the sledgehammer- I need to get the bolt open" pressures).

do shoot straight,
greg
www.gmdr.com

ps. the other point to always remember about ackley's data: most of it was taken with a ballistics pendulum, ie, a +/- 10% device, on a good day (only the very last data from the '60s was taken electronically).


Good point Greg. I'm trying to stay on the learning curve with this. The 220swift might be my varmint rifle (will pick one up in the next year or so). Thanx for the info!


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Perf -

Hard to go wrong with a 220... it's probably (long distance) flipped more chucks than all the rest combined. We shot one for years; but have since move up to the 22-250 Improved (a little more capacity, and a lot less case stretch). Just make sure your 220 has the longest barrel on it you can handle - 26" is a minimum, 28 or even 30 is nicer (with more barrel one can spread the bullet accleration out over a greater distance and reduce the barrel wear (and throat wear) back to more normal levels (less pressure over a longer distance produces the same velocity as higher pressure over a shorter barrel/distance)... and besides: flipping three chucks in a row, at 700 yards, makes for a good day (or at least ear to ear smiles).

do shoot straight,
greg
www.gmdr.com
 

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Discussion Starter · #8 ·
Greg, nothing like doing a few woodchucks/hogs in this neck of the woods! Hey, while I've got you here you'd mentioned getting the longest barrel tolerable. I'd read somewhere that the studies done on long barrels with 1in9 twist (cant remember the bullet) produced excellent accuracy at long range with considerable winds blowing. It really bucked the wind well for a small caliber. Have you heard this? I guess the results were devastating on the PD's! :lol:


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Perf -

Sorry not noticing your follow up... so a month later: unfortunately, don't have any other than casual experience with fast-twist 220's - ours were 1:13 and 1:14's (which works very well with 35-50gr bullets)... though do know other shooters with 1:9's, and as long as they're shooting 65gr'er or heavier they're happy. W/re windbucking with 1:9's - I suspect that has to do with the heavier bullets they're going to be using and not the 1:9 itself. [heavier the bullet, less it's affected by wind; likewise, less time it's exposed to the wind less it'll be affected, ie, drive the light ones fast.]Personally, if I were to go with a 1:9 (and the heavier bullets), I'd put a 22-06 behind it and about 30" of barrel to get (nominal) 220ish velocities back [I expect my 4570 to generate rainbow trajectories, but not my 220]. I know everyone has their own tastes in terms of cartridges and bullet weights - but for us we tend to use 22 cals for 30gr mef's, 35 vmaxs thru maybe a 45gr'er (like that flat flat trajectory); if we want to push more bullet, then we go to the 25-06 or even a 6.5-06 or 264wm... though not to say that one can't be happy with 69 or 75gr'er from a 22 - it's just not our cup of tea (or, maybe we're just too old school).

do shoot straight (and who says 4400fps is too fast),
greg
www.gmdr.com

ps. you might connect up with john antonies of varmint hunter - he's an absolute expert on the topic - and with many 10's of thousands of rounds of experience, and with a very sharp mind to understand what he's seeing - he won't steer you wrong... and besides he's a good joe if there ever was one.
 

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Discussion Starter · #10 ·
Greg, thanx for the comeback (and not to late, just casual chat). The fella that shoots long distance gave me a collection of his wildcat rounds and there's some good ones in that bunch. He said that for the deer he shot at 1200yds there was a witness as was for the 1600 pd. He insists it's honest shooting. The deer shot was from a 300wby mag, 40lb stock, muzzlebrake and custom 35X leupold scope. He said that he minimizes barrel jump so he can still see at range. I guess I've not hung out with the REAL long range guys before so even if half of it's true I'm learning something.

Thanx for the recommendation of John Antonies. If I get tied up with the 220 I'll need help with it for sure. I'm told that the 22-250 is less finicky when working up accurate loads. We're moving out into some open country this summer and the varmint rifle will be fun since I can see out over 500yds.

Thanx, Greg.


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