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jeff423
03-07-2009, 07:12 PM
I just cast a bunch of .44 225gr GC bullets from an RCBS mould. I have a lee .430 sizing die and Hornady .44 cal GC's.
My problem is seating the checks on the bullet. It takes a couple of taps with a plastic mallet to get them bottomed out. Fortunately it is a flat nosed bullet. The Lee does a nice job of crimping them on, after they are seated, but won't seat them.

Is this normal or am I missing something?
Do lubrisizers like RCBS, Lyman, Star, Saeco do this differently?
Is the base of my bullet too big?

TIA,

Jeff

mpmarty
03-07-2009, 07:24 PM
What is the as cast diameter of your boolit?
Is there any finning at the parting line?
Most gas checks will seat with only hand pressure and the Lee sizer works OK but the Lyman et al are able to exert pressure at the end of the stroke that can't be done on a Lee.

jeff423
03-07-2009, 07:35 PM
What is the as cast diameter of your boolit?
Is there any finning at the parting line?
Most gas checks will seat with only hand pressure and the Lee sizer works OK but the Lyman et al are able to exert pressure at the end of the stroke that can't be done on a Lee.

As cast is about .431. There is a little finning at the parting line. I'm also using a hard alloy.

Jeff

Wayne Smith
03-08-2009, 05:53 PM
Finning at the parting line is your problem. That and the hard alloy, the check is catching on the fins and is hard to move the alloy to get it fit.

Tom W.
03-08-2009, 06:15 PM
You can try a few upside down and see if that works. It did for me with a Lee bullet that just would not seat the checks correctly. I contacted Lee and they sent me a "nose profile die" which is a die that isn't drilled all the way through and has , well, the same nose profile as my bullet. I can now seat my checks with that device, then run them through the Lee sizer.. and it works!

mag_01
03-08-2009, 08:14 PM
Jeff --- If I have trouble seating gas checks I chuck the boolit up in a drill (very lose) and file the edge of the base then checks slip on easily.

Leftoverdj
03-08-2009, 08:51 PM
It's not uncommon and nothing to worry about. The mallet works fine as long as a couple of light taps are enough. The push through sizers are the best at seating checks, but your bullets are not offering enough resistance for that to work. The base first sizers are the worst because once the GC is crimped, it ain't going nowhere. If it's crooked, it'll stay crooked.

The problem is that old devil Tolerances. Bullet shanks can very several thous. So can GCs. When a fat shank meets a tight GC, it does not want to go in. Extremely sharp bases can add to the problem.

We've talked about this many a time, and got about as many answers as posters. The simple approach is to set those GC's aside for use with a mould that casts smaller shanks and try another batch of GCs.

That finning is a big part of the problem. Try running your alloy at a lower temperature. If the finning is due to a warped mould, replacing the mould is the only solution I know, but that's rare.

jeff423
03-08-2009, 11:47 PM
It's not uncommon and nothing to worry about. The mallet works fine as long as a couple of light taps are enough. The push through sizers are the best at seating checks, but your bullets are not offering enough resistance for that to work. The base first sizers are the worst because once the GC is crimped, it ain't going nowhere. If it's crooked, it'll stay crooked.

The problem is that old devil Tolerances. Bullet shanks can very several thous. So can GCs. When a fat shank meets a tight GC, it does not want to go in. Extremely sharp bases can add to the problem.

We've talked about this many a time, and got about as many answers as posters. The simple approach is to set those GC's aside for use with a mould that casts smaller shanks and try another batch of GCs.

That finning is a big part of the problem. Try running your alloy at a lower temperature. If the finning is due to a warped mould, replacing the mould is the only solution I know, but that's rare.

Thanks very much. I'll turn the heat down.
I also found with the lee sizer that if I seated one check on a bullet with a mallet and then started it in the sizer to the point that there was significant resistance I could then use the sizer to seat the next check. Each bullet and check then took two half strokes instead of one full stroke.

Jeff

shotman
03-09-2009, 02:00 AM
take your check and put it on base set on the punch and start boolit in die till it sticks. Then tap handle like you are driving the boolit into the die. about 2 or 3 sharp taps and it will seat tight.

Bret4207
03-09-2009, 07:06 AM
You can also try annealing the checks, it softens them and makes them easier to seat. Simply get a nice hot melt going and dump you checks in the pot. The checks will stay on top and gradually smoke, hiss, and turn blackish. Let them heat for a couple minutes, scoop them out and let cool or dump in some water. That's all there is to it. Sometimes just running your thumb nail along the edge of the boolit will break the edge enough for them to fit right, or you can use an outside case chamferer to do it if you have one minus the center spud.