Ok, I see, your trying to load to max specs? If 2.56 works then nothing should be wrong with teh gun. But I would load down to 2.55".

Like I said, I got a 7mm-08 that if you load to 2.8" you would never get the bullet in there. In fact, longest I can load is 2.73". Very short cut chamber. Which is fine with me.

As long as you have some cannalure on the bullet to crimp, your fine.

Sounds to me like you're trying to shoot an incompatable bullet in your gun. I wouldn't rule out a short chamber, although I doubt thats what you'll find.I don't shoot a 444 but I do shoot a 45-70 and I'm aware of the types of problems you can have with strait wall cartriges. For example I ordered some 440 grn lbt solids from cabela's and when loaded to the crimping groove they wouldn't chamber. This is a marlin 1895 by the way,.I used my rcbs lathe type case trimmer and shortened some cases .060 " and then reduced my load slighty and they were awsome. Since you didn't say what factory load gave you the problem it's really hard to help you pinpoint the cause. as was mentioned above, too much case mouth expansion followed by a heavy crimp can also make for difficult chambering. Inspect your chamber carefully before fireing with any ammo.

Why not measure your chamber for the Max OAL for your particular bullet? The way I measure the Max OAL of a bullet choice is to close the action ,insert a cleaning rod down the bore until it bottoms out on the bolt, mark the rod. Open action and insert the bullet you want to load(bullet only not a cartridge) hold the bullet against the rifling with a pencil or something, re-insert the rod until it touches the bullet tip, mark rod again. the difference between the marks is your max OAL for that bullet. Note it can change with a different bullet weight/shape.
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