Hi
I am about to take delivery of a .220 swift AI built on a savage action custom stock and heavy 30inch barrel with a 1 in 8 twist. Does anyone have experience of loading for this caliber. I don't want to "push" this rather have an accurate load with 55grns and 69/75 grns. I thought of the Hornady 75grn A-MAX bullet at around 3000fps, any help would be useful.

Many thanks

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Jim Wilson

I've been using a 26" AR-15 in .223 AI for several years tactically on coyotes `out to around 500 yds., and of the 3 bullets i've tried-- 75 A-Max, 69 Nosler Comp, and 70 JLK VLD, i've found the 69 gives the most reliable terminal ballistics out to that range (at that case's ability).

In 1986 I built up a rifle on a Rem 700 action, Douglas 25.25 stainless steel barrel with 1 in 12 twist, and chambered for the .220 Swift AI.

I tested and chronographed the 53, 55,60, 68, 69, and 74 grain bullets, and unfortunately discovered the 1 in 12 twist would not stabilise the 68 grain Hornady HPBT or the 69 grain Sierra HPBT, which had just been released in Australia.

It is important to note that there are numerous "Improved Swifts" with varying chamber dimensions, so for that reason you should not use data from other rifles. However, for the record, and to give you some comparison with your cases, the dimensions of my fireformed Winchester .220 AI cases were: Head .4420, shoulder .4346, neck .2610, shoulder angle 40 degrees, and the capacity was 55.5 grains after fireforming.

The case achieved 4,140 fps with the Sierra SPBT, 3,906 fps with the Nosler 60 grain SPBT, 3,650 fps with the Sierra 69 grain HPBT, and 3,542 fps with the RWS 74 grain Cone Point.

I believe that the case capacity of the 220 Swift AI, and 30 inch barrel with 1 in 8 twist that you are using, are most suitable for bullets in the 68 - 80 grain range.

Personally if I had your setup, I would initially concentrate on the 80 grain bullets (Sierra, Nosler, JLK, and Berger), as the 30 inch barrel with 1 in 8 twist will enable you to use the slower burning powders to get the best out of that bullet weight.

Assuming you case capacity is similar to mine, my experience with this case, the 22/284, and 224 Clark, suggests that powders such as Reloader 22, Vihtavouri N165, IMR 7828, and others of similar burning rate will be best with bullets of 68 - 70 grains. The 75 - 80 grain bullets will be best with Hodgdon 1000, Reloader 25, Vihtavouri N170, and others of similar burning rate. Good luck, and hope the above helps. Brian.