Well I got around to loading and shooting some fireformed brass for my 223 Ackley "Walk Around Varminter" (www.rvbprecision.com in the photo album). Here are some observations. First off, the gun shoots increadibly well during fireforming. No groups were over 3/4" and this was with bulk Remington bullets. Loading the fireformed brass with a 50grain Nosler Ballistic Tip bullet and 27 grains of Vit133 the bolt lift is hard and the primers are slightly cratered. This is with Remington nickle plated brass. What is interesting is if I use Winchester headstamped military brass I get extremely hard bolt lift. Why this is interesting is that the Winchester brass has more internal volume than the Remington (Rem brass holds 30.5 grains of water and the Win brass holds 31.8) You would think the Rem brass would show much more pressure. Comments?

While I was fooling around with internal volume, I measured some other cartridges for comparison.
222 Mag = 31.6 grains of water
223 Ackley = 31
223 = 30
22 PPC = 31.1
22BR = 37.9

As you can see, there is very little "improvement" from the standard 223 to the Ackley. It would appear to me that the 222 Mag would be the idea cartridge. You could simply run a 222 Mag Ackley Reamer into any 223 chambered rifle without setting the barrel back and I'm guessing the "improvement" would be about 12%. I have a 223 Contender barrel that Mike Belm rechambered for me in 222 Mag Ackley, but I've never shot it. Guess I'll have to do this and see how it works out. I see an order for a 222 Mag Ackley reamer in my future....

My load development is going as follows. So far I've only used 40 and 50 grain Noslers. I always use moly in varmint (high rate of fire) guns. With any load I've tried the gun is shooting under a half inch. (love those Pac Nor barrels!)

My best groups so far are with 40 gr bullets and 27.5 of vit 133 for a speed of 3700 fps and a SD of 6. Groups averaged in the 3s. Although this is great. I expected to be approaching the 3900 fps mark. I can get 3700 with a 40 grain moly bullet out of my standard 223s.

I found 50 grain bullets work much better with the slower Vit 135. 27grains of Vit 135 under a 50g NBT gives me 3400 fps. The average group is in the high 4s. Again, not bad, but not worth the extra work of the Ackley fireforming and rechambering.

So where does this leave me. Trying more bullets and a few more powders to see if I can edge the velocity up a bit without pressure issues.
Any comments?

RVB.....unless you have a typo on the capacities listed I don't see where 12% comes from...all you list is a change from 31.0 to 31.6 for volume looks like not quite 2% to me. This would mean a load that was getting 3500 fps would now do 3520 fps.

Why don't you ask Genghis, he thinks this round is the greatest thing since poptops.

So do I,so do I...............

My guess on the hard bolt lift with Rem nickle brass verse Win Mil brass with extremly hard bolt lift is that nickle is harder and smother then bare brass. Nickle should not stick the the chamber as hard as bare brass. Try some other brands of nickle and standard brass. Get some non-nickle Rem brass to try verses the Rem nickle brass.

Kristofer