I have just started reloading for my 300 WSM and have struck a problem with my Lee F/L sizing die. I wondered if anyone has had a similar problem and how they fixed it.

After f/l sizing once fired factory loads (in my rifle) and running these through the Lee f/l sizing die it has become clear that this die is not full length sizing all the way to the rim of the case.

As a result when I chamber an empty case in the action of my rifle, it goes in easy up to the point where I close the bolt. Its then real stiff to finally close the bolt during the camming action. However a factory loaded round is no problem at all.

These f/l sized cases are also hanging up in the last quarter inch when trying to seat a projectile using the bullet seating die.

The difference in width between a factory unfired case and a f/l sized case just forward of the rim is five thou.

It appears that the Lee f/l die is not resizing the case in the last quarter inch or so, forward of the rim and it can be seen visibly.

I have tried playing with the die set up to see if that would help, but no change. The last quarter inch of the case remains unsized.

I have Lee dies in other calibers and have been reloading them for years and have never struck this problem.

Any "pearls of wisdom" would be greatly appreciated!!

I have that same die w/o any problems. Most dies will not size a case back to the factory dimensions, close but, not exact.

It is noty common at all for a die not to size the entire length to the rim of the case infact, most don't. Have you tried to screw the die in at 1/2 turns and size a case? Any difference?

Sounds like you might have a real tight chamber.

Have you called Lee's customer service? If you got a bad one they should replace it.

Redding makes some nice full length dies if the Lee doesn't pan out.

Good Luck, I hope you get it ironed out.

Reloader

Have you tried just neck sizing the case?

My 300WSM seems to require a little 'extra' Fl sizing...i.e. polishing off a few thousandths from the shellholder (for my RCBS dies) to get the die down enough to just partial FL size...and thats with a firm camover at the end of the press stroke.

It seems to me that the high pressure coupled with the wide shoulder required a bit more to get the shoulder pushed back enough for easy chambering.

I highly doubt the resistance you are feeling during closing the bolt is the slight bulge at the casehead...much more likely the following:

1) during FL sizing, the first case to die contact is squeezing the sides of the case in. This causes the shoulder to move forward, much like squeezing a cylinder of play-do in your hand causes it to push out the sodes fo your fist.

2) now the shoulder is even farther forward than when fired, and requires more to 'bump' it back to where the cartridge can be easily chambered.

Try lowering the die another 1/4 turn and see if your problem goes away. Good luck!

Thanks for the suggestions guys. I have already covered most points that have been mentioned.

CDH

I will try a ground down shell holder tomorrow and see if that helps - thats a good idea. Failing that I now can get access set of second hand 300wsm dies (Redding) and see if they do a better job.

I doubt its a tight chamber on my rifle as factory Winchester ammo chambers with ease. I think the factory ammo is pretty hot and this is most of the problem.

MLG - I had the exact same problem with my newly acquired 25 WSSM and discovered I was using a "neck sizing die" instead of the full length resizing die I normally use. However I had the die adjusted 1/4 to 1/2 turn against the case which I discovered was not necessary and was I believe causing the problem. I backed off the die so it just barely touches the base of the cartridge case and it totally solved the problem. Hopefully you will find a solution.

+1 on shaving a shellholder down. I have an extra one sitting here that I took about .020" off of for this reason. The wsm is a really beefy case and can have alot of "springback" after sizing. I will bet a 12 pack that you will get the full sizing needed after doing up a shellholder. I get sick of all the "camming over" on alot of different cases and the shorter shellholder takes this action off the press.
ALSO- I think you said you were having trouble "seating" bullets. This most likely means your seating die is tightened down too far in the press and is beginning to crimp before you have the bullet fully seated. Back out the die another turn out two and then crank down your seater adjustment to make up for it.

A question
Do you put a bit of lube on the case mouth, something like motor mica?
I had a similar problem and found that as the case was withdrawn from the die the neck expander was pulling the case neck forward a bit, making chambering tight.
Jim

quote:

Originally posted by Roybean:
MLG - I had the exact same problem with my newly acquired 25 WSSM and discovered I was using a "neck sizing die" instead of the full length resizing die I normally use. However I had the die adjusted 1/4 to 1/2 turn against the case which I discovered was not necessary and was I believe causing the problem. I backed off the die so it just barely touches the base of the cartridge case and it totally solved the problem. Hopefully you will find a solution.

Welcome to AR....and a fine starting post indeed...thanks.