New problem, need expertise!

[BillR]

I've been using a .25-06 AI for a few years now and have never had this problem. I use LC .30-06 brass and neck it down in two stages. First .270 and then .25-06 and then trim to length. I have a tight neck chamber so I have to then turn the necks down to the right thickness and trim to length and then anneal it. I then load it with a load I use in my other .25-06's with a cheap bullet and fire it. Comes out right every time. I do end up with a slight bulge upon resizing from where the old .30-06 neck was just below the .25-06 neck and if I don't get this sized just right I cannot chamber the round. It might be that is the reason I'm not having the bulge problem. The slight bulge helps with the head spacing and keeps it tight against the bolt. The bolt also has a Sako style extractor so that might help also. One thing I did find to be critical though was to anneal the case again after fire forming. If I didn't I ended up with a neck that would not hold the bullet tight. I re-size the case to about .003 smaller than the chamber neck and it works great. Took me a lot of playing around to get everything just right but once I had it all right it shot like a dream with no case problems. Annealing was the secret with this gun. That and getting the case neck thickness just perfect. I have never tried it with .25-06 Factory brass as I have too many .25-06;s to feed to waste the brass on this project and had a ton of old LC once fired .30-06 brass that could be destroyed if it didn't work right. Usually after the second firing the cases once tumbled looked like brand new brass and from then on all I do is neck size them. Something else is that I trim the cases to standard .25-06 case length and I don't really see how with all this you could be off on head space. Great gun and cartridge if you like to tinker.

[Coyboy]

If an ackley chamber is headspaced properly seating bullets into the lands is completly unneccesary when fireforming.

Heres why, a standard 25-06 chamber is cut to the go gauge, or with-in a thou or two. This allows the bolt to close on new brass with no resistance.

An ackley chamber should be headspaced to about .004" bellow the standard 25-06 go gauge. This is so that when the bolt is closed on new brass, there IS RESISTANCE. That resistance is the leading edge of the case shoulder being crush fit into the chamber shoulder at the neck juncture.

When done this way the brass can not move forward from the plunger(although I like Chads Idea of removing it) or from the fireing pin strike. It is locked in place so only the shoulder and case walls are expanded, and the web does not stretch.

If at all possible when you have an akley built send the smith 20 pcs of brass from the same lot, that will feed the rifle for it's life. Then smith can modify the headspace to put a precise crush fit on the brass YOU will feed the gun. Now the whole web stretching issue is a nonissue.

This is also why a factory tube can not be acklied properly without setting the barrel back some to produce the crush fit.

Now the problem with your gun as I said earlier, UNDERSIZED brass at the web dia. (measure your webs and compare them to a saami spec for that chamber) did you try that yet? The other possibility is an oversized reamer created a chamber that is a touch too big. But my bet says it's a brass size issue, I seen it on a 280 ackley with rem brass that measured .464" at the web.

[Crane]

Measured the brass at the bulge and got .4755 Just got the gauge from Kevin in the mail moments ago, I'll try and call him later after the Alabama - LSU game...of course Penn State may be on then and he won"t answer. Just bought a bag of .270 brass, some Blue Dot and bullets. I'm gonna try Boss Hoss's and Chad's method compared to fire formed factory loads. This may be a silly question but is there any problem necking down a false shoulder on the .270 brass to .257 with bushing dies? Running a .281 for the Remington brass. I've heard a regular full length die may be preferable or even required. I can't thank everyone enough for sharing their knowledge. Hopefully I'll have a chance to pass this all on to the next guy.