case resizing boolits??

[LKTTU]

my boolits measure .452 after casting and sizing, then I load them up, if I pull a boolit after loading it, it measures .450-.451. I think this may be causing my leading problem. What can be done to solve this? Maybe a harder alloy?

[Mal Paso]

Get a .450" or larger expander die, try again. The RCBS Cowboy Expander is .452". Then try a Harder Alloy.

[R.M.]

Back off on the crimp.

[mdi]

Yep, tight cases can swage a lead bullet. Mal paso's post is best advise I know (he beat me to it), and definately stay away from Lee's FCD...

[918v]

I recently tested this: I seated .358" BHN 12 bullets into a WCC 9mm case that was flared only by the use of a universal flare only die (doesn't have a plug that goes inside the case to expand the walls). The bullets were swaged down by .0002" at the base.

This is the most extreme scenario one might encounter, i.e. a military 9mm case with thick and hard case walls, minimum internal diameter, and a soft oversized boolit. Aaaaaand practically no swaging!

This is a non issue.

[462]

I've experienced two causes of boolit swaging:
An expander plug that is too small in diameter and too short in length. I prefer a plug that is .002" less in diameter and the same length as the boolit.
Lee seating dies.

Another possible cause:
Seating and crimping at the same time. Seat in one step and crimp in another.

I've no experience with it (and never will) but many members find much fault with Lee's handgun factory crimp die.

[oldandslow]

lkttu, 9/10/12

I had the same problems resulting in much leading in my barrels. I was unable to find a larger expander die so the simple solution was to quit sizing my boolits. My molds drop the boolits 2-3 thousandths larger than the pistol bore and when loaded into the brass the swaging by the brass dropped the bullet diameter to 1-2 thousandths over the bore diameter, thus no leading. Maybe give it a try and load un-sized boolits and then pull a few and mic their size. Good luck.


best wishes- oldandslow

[geargnasher]

Most expander dies are too small for cast boolits because they're designed to provide good grip on projectiles that are both smaller and harder than cast. Either a larger expander or harder boolit will help, and as has been mentioned, make sure you aren't over-crimping or using the dreaded Lee factory crimp die for pistols with the carbide post-sizing sleeve. That die is meant for copper-jacketed dimensions, many times it will swage down our larger cast boolits when post-sizing the case.

If you're using a Lee expander, a little trick that works well is to heat the tip of the expander spud red hot and air-cool it, then expand the tip SLIGHTLY with a tapered punch, which will make it expand the brass more. But BE CAREFUL here, you can easily split the tip of the spud, and you can also expand your brass too much, which will cause insufficient boolit tension which can lead to telescoping of the boolits under recoil forces in the magazine, and if you chamber and fire a telescoped boolit, it can overpressure the case.

Much of the time .45 ACP brass is soft enough to expand to accomodate even moderately soft cast boolits when the factory expander is used. If you're experiencing swaged boolits in that caliber, I suspect your alloy is way too soft or you're killing it with crimp. 9mm and .40 S&W typically need a super-hard alloy or custom expanders that are longer and larger than any factory ones to keep the boolits from being squished when seated, but that's due to the MUCH thicker, tougher, and harder brass of those little magnum-pressure calibers. .45 ACP is a cream-puff.

Gear

[Seth_AZ]

I recently tested this: I seated .358" BHN 12 bullets into a WCC 9mm case that was flared only by the use of a universal flare only die (doesn't have a plug that goes inside the case to expand the walls). The bullets were swaged down by .0002" at the base.

This is the most extreme scenario one might encounter, i.e. a military 9mm case with thick and hard case walls, minimum internal diameter, and a soft oversized boolit. Aaaaaand practically no swaging!

This is a non issue.
It was a non-issue to you. I have just been dealing with this last week on my end, and with my alloy (WW with around 10% added lino and a little tin, air cooled). I definitely saw a reduction of .002-003" or so along both driving bands, and even more at the very *** end of the bullet, where a little mini-boattail was swaged into the sharp corner of the bullet.

Here's a link (http://www.leigh.org/seth/pulled_bullet_web_0029.jpg) to the final image I posted in my 9mm range report thread. That boattail reduced the diameter of the already-reduced rear (main) driving band by nearly 50% of its length. Hardly a non-issue.

That bullet was seated into a 9mm case that had been expanded with the standard Dillon 9mm powder funnel.

[Forrest r]

The lyman m-die works wonders with cast boolits. They cost around $17 & save a lot of hair pulling head scratching & time.