I switched does from a lee fl sizing to a forster bench rest fl die honed to .336 for lapua brass. Now the problem is the some of the brass won't hold the bullet. It just falls in. It isn't all of the brass though, just about 50% of them. I've made adjustments but it won't compress the neck any. Suggestions??
- Thread starter HawkDriver
- Start date
Try annealing your cases. Maybe the ones that aren't holding the bullet are work hardened and are springing back too much.
I annealed all of them. The lee die brings the neck size down but the forster does nothing.
I think .336 may be a bit too much but when I put a case from the lee die in the forster, it doesn't expand it at all.
Do you have an expander ball in the Forster? If you have the die neck honed to .336 you shouldn't need the expander ball.Try sizing them naked (without the ball.)
Neck honed to .336 yields approx. .3365"-.3375" OD neck depending on brass thickness.
lapua .308 brass necks avg .0145"
Avg OD neck .3370" - (.0145x2) = .308" which depending on your bullet may or may not be enough neck tension to hold your bullet. Coupled with some properly annealed brass and some not annealed quite enough, differeing brass neck thickness, you will see some bullets dropping through the neck.
Your lee die is made to size smaller and then the expander ball will open the neck up so the neck isn't too small but enough to maintain about .001" neck tension per the factory.
My guess is your neck is probably honed out a little too much. I'd try for a .334-.335" honed neck depending on whether or not your turning brass and what your brass neck thickness is.
lapua .308 brass necks avg .0145"
Avg OD neck .3370" - (.0145x2) = .308" which depending on your bullet may or may not be enough neck tension to hold your bullet. Coupled with some properly annealed brass and some not annealed quite enough, differeing brass neck thickness, you will see some bullets dropping through the neck.
Your lee die is made to size smaller and then the expander ball will open the neck up so the neck isn't too small but enough to maintain about .001" neck tension per the factory.
My guess is your neck is probably honed out a little too much. I'd try for a .334-.335" honed neck depending on whether or not your turning brass and what your brass neck thickness is.
0.336 is a little large for a neck bore or bushing. Brass necks will always vary in thickness due to the drawing process. The brass will be thinner in the areas that lie in the direction of the metal grain and thicker in the areas across the grain. The thickness will only vary about a half thou. around the neck. The only way to uniform this is to neck turn. 0.336 would take a neck thickness of 0.015 after turning which is thicker than most Lapua necks. The couple of batches I've measured was about 0.014 with areas of 0.0135. Lapua has very consistent neck thickness but the only way to ensure true uniformity is to turn the necks. This would result in a neck of about 0.013 but everybody I know that turns 308 necks set it up for 0.012. This way the thinner Win and RP and Fed brass will size like the Lapua in the same die. Also, when a neck bushing in a type "S" die is labeled 0.336 it means the bushing will produce brass with an OD of 0.336 so the actual bushing bore is about 0.0015 smaller in diameter. You probably need a 0.334 bushing or a honed neck of about 0.332. I wouldn't go out and start neck turning I'd just get a smaller neck bushing.
I turn my necks to .014-.0142" on my lapua brass. I use a .3330" honed neck for a finished neck of .334-.3350 depending on the firing cycle of the brass. This leaves me with about .001-.002" neck tension on a .308" bullet.
HawkDriver ......
You now have a die that's only good for cases with one specific neck thickness. That's why Redding (and a few others) make bushing type dies. They have the advantage of not needing an expander ball, and you can full length resize your cases with brass of any neck thickness - just select the appropriate bushing.
You now have a die that's only good for cases with one specific neck thickness. That's why Redding (and a few others) make bushing type dies. They have the advantage of not needing an expander ball, and you can full length resize your cases with brass of any neck thickness - just select the appropriate bushing.
