45ACP Key holing target

[wind power]

Hi Folks first time poster.
I'm having a dilemma with a 45acp round I have worked up.
The bullet is 200 grain (actually weighs in at 215 grains) and is a LEE double cavity # 90234. (It is flat nose style bullet) after casting the bullets mic consistently at .451-452 and I'm using surplus wheel weights which I melted down....(I kept the temps low so as not to have any zinc wheel weights introduced into the mix)

At 10 yards about 50% of the loads will key hole the target.
I’m firing them from a Bersa Compact pro about a 3.5 inch barrel which has polygonal rifling. I feel the pistol is ok because it will shoot 230 grain FMJ's like a house a fire easily keeping them inside a 4 inch circle at ten yards...however the cast bullets open up to an area of about 6 inches and begin to keyhole

I first thought it was from not flaring the case mouth....I had about three bullets shave some lead off out of about ten rounds which I first thought was the key holing suspect but it was more than 3 rounds which key holed.

So I loaded up another 14 rounds but this time I flared the case mouth to rid myself of a round or three shaving some lead and gave them an ever so slight taper crimp after seating the bullets (I’m aware of 45 ACP head spacing off the case mouth so I kept the taper crimp to a minimum.) However after loading these 14 rounds without any lead being shaved at the case mouth... it still Key holed!

Here are some more things:
The barrel is not lead fouled
I lube the bullets well with Lee Alox
A mix of various brass
5.6 grains of Red Dot is what I'm pushing them with
Any Ideas?

[Lee W]

You are way over max for lead boolits.

http://www.alliantpowder.com/reloade...id=62&bdid=180

[wind power]

Hi Lee,
Thanks for your reply....I see it is a hot load...too hot in fact...I ahve a Lyman manual which lists it a bit close to my 5.6 load of red dot, but it is at 5.3 grains max...I will reduce the load and see what happens...but I have a funny feeling it wont stop the key holing....I've never had any round before to ever key hole on me like this one does...been firing thousands of rounds since the mid 70's and never had this to happen???? However this is my first Polygonal Bore rifiling.....I'm wondering if the rifing is my culprit?

Back to that hot load..... I propblay wont find 5.6 grain load of Red dot in any manual after the 1970's.....ahhhh the good ol days when companies didnt have to deal with lawyers

[RobS]

5.6 of Red dot is a bit on the warm side however key holing isn't necessarily this issue. I suspect that the boolits are too small for the bore. Have you slugged your bore? Also have you pulled a loaded boolit to ensure it is coming out of the case at .451-.452; it could be swaged down (squeezed down) in the reloading process of seating/crimping. With polygonal rifling it also helps to have a harder boolit so it doesn't skid the rifling. Maybe water quench those WW boolits as something to try.

[Iron Mike Golf]

+1 on what Rob said. Check your barrel for leading. What's your lube? What's the air temp where you shoot? Boolits are wobbling, so I'd wonder if they are spinning fast enough to be stable or out of balance.

And work up from min charge, not down from max.

[wind power]

Hi Thanks for the info, I will drop the powder charge and pull a bullet to see what I have on the OD.
I will also slug the bore and check what the dimensions are there too.
I will water quench the bullets as they come out of the mold.
Thanks for the ideas! It gives me a good starting point!

[Bret4207]

Start at square one- do one thing at a time. See what size they come out of the case. Good chance they're being swaged down. Your barrel may require a fatter boolit. Don't go harder till you figure out the fit issue- FIT IS KING in cast. Start with fit and use Bhn as the tool it is. Harder won't fix fit issues.

[subsonic]

Member of the "harder (tougher) is better" club checking in here.

If the brass is sizing the boolits down because they are soft, the answer seems obvious. Also, you want some neck tension if you can possibly get it. You can't (shouldn't) roll crimp a rimless case, and a firm taper crimp will make things worse. So you don't want to expand the brass more to reduce the sizing, if you can avoid it.

[MtGun44]

Keyholing is almost always caused by inadequate spin, which is almost always (in pistols)
caused by undersized boolits. Might actually need a harder alloy (the rest the folks here
will note on their calendars the day that I suggested a harder alloy !! ) due to
the poly bore - never dealt with one before at all, let alone in .45 ACP although I have
loaded many hundreds of thousands of this cartridge over the last 3 decades +.

Poligonal bore needs to be slugged and then you need to verify (like Bret said) that you
are delivering a ~.001 larger than groove (if that is the correct term in a poly bore) diameter
boolit to the barrel, not resizing in the case.

Are you by any chance using a Lee Factory Crimp Die? If so - STOP IT, and try some without
this unit. We have had many situations where the Lee pistol FCD was the problem, sizing
down the boolit in the case. I am NOT a fan of this device.

You cannot taper crimp enough to cause any headspace issue, so remove the barrel and
set the LOA to keep the boolit shoulder from jamming into the rifling too much and the TC
to make the round drop freely into the chamber.

Try a more reasonable load, say 850 fps for that boolit and you may help things.

Bill

[wind power]

Ok I did a few things today.....
After slugging the clean barrel the slug measured .4505-.4510
I also used an inertia bullet puller (Hammer type) and mic a loaded crimped bullet, that bullet mic at .450

I drop the pweder charge down to five grains even of red dot and out of 7 rounds 1 key holed....eachy powder charge was individually weighed and was with a tenthy of a grain.

on the slugged polygonal barrel, it was.443 on the groove side

[subsonic]

There's your problem right there. Undersized boolits that are stripping the rifling, and not spinning up to stabilize properly.

[Forrest r]

I don’t know about your load being way over max. Hot, yes. Max no. I see people using reloading data for swc boolit instead of a RF bullet all the time. An RF boolit has more weight in the nose of the boolit than a swc boolit. That creates a small boolit shank on the RF boolit. A smaller shank =’s greater case capacity or more volume left in the case after the boolit is seated. A smaller shank =’s less resistance & less resistance =’s less pressure. Here’s a pic of a lee RF boolit next to a typical (452488) swc boolit.

[IMG][/IMG]

As you can see a typical swc boolit seats allot deeper than an RF boolit.

I’m on the other side of the fence on this one with you needing a harder boolit. Right now you’re using a water quenched boolit made from straight ww to make them even harder & are then driving/shooting those at a whopping 750 to 800fps in that short bbl’d pistol.

I’m more inclined to say use a softer boolit so it can obulate in the bbl to seal it & use a boolit the right dia for your bbl & your key holing problems will go away.

[462]

. . . the slug measured .4505-.4510.
. . . that bullet mic at .450.

Your boolits are being swaged down and are too skinny. Dies are manufactured to jacketed bullet dimensions. When loading cast boolits, we need to do things a bit differently.

My remedy would be to use a Lyman expander die (M-die) to properly expand the case to accept a .452" boolit (cull any that are skinnier). A typical expanding die only "flares" the mouth, which may allow the rest of the case to swage down the boolit. Also, apply a light taper crimp (just enough to chamber the round) using a conventional crimp die.

With a properly expanded case, there will be no need to water quench. However, I will defer to those with polygonal experience as to boolit hardness.

[Bret4207]

Member of the "harder (tougher) is better" club checking in here.

If the brass is sizing the boolits down because they are soft, the answer seems obvious. Also, you want some neck tension if you can possibly get it. You can't (shouldn't) roll crimp a rimless case, and a firm taper crimp will make things worse. So you don't want to expand the brass more to reduce the sizing, if you can avoid it.

With all due respect, if his seater is swaging the boolit down, the hardest alloy he can get will still get swaged down. Using the proper tool (M die, opened up seater, whatever) is the fix, not a different alloy. Hard or soft, FIT is still King.

[subsonic]

I don't think I agree that harder will swage down.

I can seat a .358" boolit cast of WDWW (20BNH on my LBT tester) in a .357 case that measures .350" ID and it comes out .358" when pulled.

Not wanting to argue, just sharing what I've done and seen.

[subsonic]

I also worry about boolits being seated deeper in an auto when they slam into the feed ramp, which can cause pressures to climb. We all agree that taper crimping can cause trouble, so all you have to depend on to fight this problem is case neck tension.

[MtGun44]

"We all agree that taper crimping can cause trouble"

No. IMO, the only trouble I have ever seen from taper crimping is a LOT of it
from inadequate taper crimp or no taper crimp.

Never, ever have seen a case of any problem from using a taper crimp.

Bill

[subsonic]

I guess we don't all agree.

[MtGun44]

we agree on a lot, just (apparently) not TC.

Doesn't mean we can't be friends!

Bill

[Bret4207]

I don't think I agree that harder will swage down.

I can seat a .358" boolit cast of WDWW (20BNH on my LBT tester) in a .357 case that measures .350" ID and it comes out .358" when pulled.

Not wanting to argue, just sharing what I've done and seen.

That can happen, yeah. But we've seen way too many people using rock hard boolits that still get swaged down. Done it myself with boolits that approach 30 Bhn. The guy on the handle of the press makes a big difference that no Bhn reading will fix. Heck, there are people out there swaging jacketed boolits in FCD's!