Chambered too tight on 280 AI?

[GaCop]

I'm experiencing a dilemma in regards to my sized 280AI brass, I'm loading Nosler brand. It's been loaded approximately four times now with the brass being neck sized in a Lee collet die with a polished mandrel.

Shooting at the range yesterday I realized the rounds were chambering pretty hard. Accuracy was not up to par on any of the loads fired even though they shot well the last time out. Some brass was hard to extract with a hard bolt lift even thought the loads were well below maximum.

I decided to re-size the brass using my Redding bump die. It didn't do one bit of good as the sized brass was still chambering hard. I trimmed all the sized brass to the length of the shortest case which was 2.517" thinking maybe my brass was too long....still no change in the effort to close the bolt.

Plan B - I then utilized the Redding f/l die adjusted for camover at the top of the ram stroke when the die contacted the shell holder on my RCBS Rockchucker Junior and the results was the same? The bolt closes a little easier now but there's still resistance when I close the bolt on a full length sized case as if the bump die and f/l die are not sizing the case shoulder enough. Could I have set the headspace too tight when I installed the barrel? Bad Lee or Redding size dies?

[trappst]

Screw the FL or body die down in small increments until they chamber freely. If you run/have run out of room, call Redding and see what they say.

I had to send a 223AI FL die back to them once for a similar situation. They ended up taking a few thou off the bottom of the die.

[Elkbane]

Tom,
You gotta check and see where the contact is, otherwise you're shooting in the dark. Draw 4 parralel lines on the case with a magic marker from extractor groove to the case mouth. Then chamber the case and lift/drop the bolt several times. Could be as simple as the shoulder has gotten work hardened and is not "accepting" the bump you're trying to put on it from the dies. Annealing will fix that, but until you know where the contact is, it'll be devilish to fix. Redding's comp shellholders are good for this - the have graduated heights for more/less bump so you don't have to keep resetting your dies......
Elkbane

[trappst]

Elkbane has a very good point! Find out what's going on in that die......I did the same thing with my 223AI but I just smoked the upper half of the case with a candle.

Remember to clean your chamber when done.

[Blue Avenger]

measure the bottom of the case, about 3/8" from the bottom and check it against factory spec.

[sharpshooter]

That is a typical dilemma when using collet dies. After about 4 firings the brass work hardens to the point is cannot be bumped even with a full length die.
My advice......nix the collet die and FL every time. You'd be better off starting with new brass too.

[mytwo60]

I don't get why folks neck size only. I've tried that and my groups opens up to almost an inch and when I FL I shoot in the .3s and .4s.

I always anneal my brass after the 3rd firing. If I don't I'll get hard bolt lift and flyers.

[GaCop]

Many good points brought up. I didn't know the Lee collet dies was a bad idea! I'll smoke the case to see whats going on.

[GaCop]

280AI problem is currently on the back burner since my Shilen 1/8tw 223 Wylde chamber barrel arrived from Northlander, back to playing with the 223 cartridge.