Does any one have one of these and what is your opinion of it. Been thinking about building one with 8 or 9 twist to shoot 75 or 80 gr. Any comments?

I don't own one, but have goo friends who do, really helps for case life and reduces trimming. Just don't go overboard on trying to increase velocity.

I have one, it's my primary coyote rifle, originally a Swift, now on barrel no.3. It will pick up about 100-150 fps or so over the standard Swift, with better case life and a bunch less trimmming. Mine is a 1 in 12, so I don't shoot the ultra heavy bullets, although I imagine the 9-inch twist would work and shoot 55's very well also. I've not seen overstabilization of a shorter bullet be much of a problem. Mine is a custom 700 built many years ago by Ed Brown, and now has a Douglas barrel and will shoot .3 pretty much always, and has gone as low as .190 at 100 yards.

It sounds pretty much like the 5,6x57 RWS which i have , that can send a 50 grs bullet in 1200 ms! and a 75 grs bullet in 3410 fps.

Is there any published reloading data for it?

Look on SMALL CALIBERS Forum for a photo of mine. Use standard Swift data to start. You may not see much inprovement, depending on your brand of brass and it's capacity compared with the Swift.

Ray

quote:

Originally posted by mr rigby:
It sounds pretty much like the 5,6x57 RWS which i have , that can send a 50 grs bullet in 1200 ms! and a 75 grs bullet in 3410 fps.

Sorry, but no. The 5.6x57 is a 7x57 necked down and the 220 Swift is based on the 6mm Lee Navy. The LN case is .445 case diameter, as opposed to .470 for the 7x57.

quote:

Originally posted by sasquach:
Is there any published reloading data for it?

If you can't find it, try looking for data on the 220 Weatherby Rocket and 220 Wotkyns-Wilson Arrow.

The 220 W-W A can be found the book Wildcat Cartridges volume 2

jstevens, How long did your barrels last?

They will last at least 4-5000 rounds. I think the last one had 4000 or so and would still shoot 3/4 inch groups although the first three inches of the bore looked like snake skin. It was a solid .5 rifle in its prime. The current barrel is a Douglas, as was the 2nd, the others were Shilen barrels. The others were standard twist, this is 1 in 12 and is the best shooting one of the bunch. I load 47 grains of H414 with a 55 Sierra for right at 4000 fps. 43.5 grains was always the limit with the standard .220 and would go 3850 fps in most rifles.