Lee custom 8mm Maximum - first cast

[Dutchman]

Recent MidSouth purchase of the Lee custom 8mm Maximum.

One cavity has a hang up at the gas check shank. I just did the Leementing using JB Bore Cleaner for 30-45 seconds on low speed using a drill motor. In the lathe I drilled and tapped 10-32 and left the tap in place as a driving shank. I haven't tried it again yet. I'm using 50:50 wheel weights/linotype.

Body diameter .326"
Nose diameter .320"

Took quite a while for the mold to start dropping good boolits. I clean molds using automotive starter fluid (ether spray) as it evaporates fast and does a good job. Then I smoke the cavities using a stick match. It still took quite a while but eventually it was sticking nice bullets (as opposed to dropping them). I hope the Leementing job cures the gas check shank sticking. Both cavities did it but the outside cavity was far worse.

Haven't weighed them yet.

I currently shoot:
1889 Swedish rolling block 8x58R Danish
Gewehr 1898 8x57
Yugo'fied K98k 8x57
Czech 98/22 8x57
Czech Persian 98/29 8x57

The Swedish rolling block originally shot a 236 grain bullet so this 8mm Maximum should do very well in the fast twist of the rolling block. My rifle is quite accurate so far. I hope it feeds ok in the Mausers.

I'll probably first try sizing to .325" in the Lyman 4500 first using BAC lube. I need to lap out a Lyman sizer from .323" to .324" before I can go further.

I'm currently casting the Lee 170 gr 8mm and Lyman 323470. I do have a quantity of purchased Lyman 323471 (215 gr) and the Czech Persian 98/29 really likes them. The Persian also really likes the RCBS .32 WCF 170 gr flat point sized .323". Just one of those rifles that likes what it likes.

I was a little concerned that maybe this 8mm Maximum mold would drop grossly oversize boolits like the Swede cruise missile and be a 2nd useless mold but it doesn't look that way so far. I like the bullet as it is but I haven't shot it yet.


Dutch

[excess650]

Dutch,
I purchased one of those back in the spring. Mine cast with dimensions similar to yours, and dropped pretty easily despite their length. I had cleaned my mold like I do all of them using dishwashing liquid, hot water, and an old toothbrush. I did not smoke mine, and prefer to cast without any smoke or mold prep. I do recommend Bullplate for the sprue cutter and alignment pins.

My 1944 K Kale Turk does OK with this bullet despite a worn bore than seems to have a less than uniform diameter. When seated out to just kiss the rifling, the bullet is pretty deeply seated, but still feeds only singly from the magazine.

[Moonie]

My Karibiner seems to hang exactly the same way and needs a few taps to get it out. I do need to lap it out. I have lapped my handgun molds however I am worried about lapping enlarging the gas check shank.

Anyone have any suggestions or thoughts on this?

[excess650]

Don't get carried away with the lapping. Use JB Bore cleaner, toothpaste, or scouring powder like Comet or Bon Ami. It may only take a few turns of the boolit in each direction to get rid of the burrs.

BTW, my 8mm Maximum weighs in at 250gr with GC and lube.

[skeet1]

Dutch,
Some of the starter fluids contains some lubricant with the either to make the use of it not so hard on engines and that may have been why it took a while for the mold to start throwing good bullets. I use acetone as a mold cleaner and it works very well. Others use disk brake cleaner and carburetor cleaner but I have no experience with these.

I have wondered how this bullet will work in a model 98 Yugo please let us know when you try it out.

Skeet1

[Dutchman]

My Karibiner seems to hang exactly the same way and needs a few taps to get it out. I do need to lap it out. I have lapped my handgun molds however I am worried about lapping enlarging the gas check shank.

Anyone have any suggestions or thoughts on this?

I'm going to do some more casting this afternoon so I'll report back here if the Leementing solved this issue. Technically, the Leementing process using JB Bore Cleaner isn't lapping, per se. It's several degrees shy of actual lapping but with Lee and Lyman molds the JB does a fine job at whatever it does to make the bullets drop easier and to clean out the cavity. So far it's all I've used.

I wasn't tapping.. I was BEATING the handle hinge to get that 2nd slug out. I use an ancient leather mallet for casting.

Dutch

[Dutchman]

Dutch,
Some of the starter fluids contains some lubricant with the either to make the use of it not so hard on engines and that may have been why it took a while for the mold to start throwing good bullets. I use acetone as a mold cleaner and it works very well. Others use disk brake cleaner and carburetor cleaner but I have no experience with these.

I have wondered how this bullet will work in a model 98 Yugo please let us know when you try it out.

Skeet1

Duhhhh... Yeah, I was sitting there looking at the bullets as they dropped/stuck and said to myself, "self, sure looks like some residue in the cavity". I did burn off some but apparently there was some oil as you say left. It did go away eventually. I think I may do the detergent/toothbrush treatment mentioned. I did 3 more Lee molds last night with the JB as they were all new and one Lyman 314299 as it seems to have needed it but the real problem was the alignment pin holes need to be chamfered.

Dutch

[Dutchman]

The one on the right is the worse of the two.

http://images109.fotki.com/v146/photos/4/28344/9430776/DSCF2845bc-vi.jpg

Easy to see why. The mold blocks are uneven.

I Leemented last night and just finished casting some more. It's much better but that one is still sticking though not nearly as much. I may do it again and I may ponder putting it in the mill and skimming the top of both blocks just enough to even them out. Probably .005" or so. There seems to be enough gas check shank for that.

http://images54.fotki.com/v452/photos/4/28344/9430776/DSCF2859bc-vi.jpg

http://images56.fotki.com/v127/photos/4/28344/9430776/DSCF2862bc-vi.jpg

http://images12.fotki.com/v254/photos/4/28344/9430776/DSCF2844bc-vi.jpg

[mpmarty]

My Karibiner seems to hang exactly the same way and needs a few taps to get it out. I do need to lap it out. I have lapped my handgun molds however I am worried about lapping enlarging the gas check shank.

Anyone have any suggestions or thoughts on this?

Open the sprue plate and pour lead into the cavity until it almost reached the gas check ledge. Use that for lapping and the gas check area doesn't change.

[excess650]

The problem doesn't appear to be the cavities themselves, but rather, the blocks aren't aligning vertically as they should. The steel pins inserted horizontally and their mating recesses may need to be deburred. Likewise, deburr the bottom and side mating surfaces of the blocks. You CAN do the top split line provided that you don't go all the way to the cavities, otherwise, you'll end up with long whiskers on the bases.

Deburr and CLEAN with dishwashing liquid, hot water and a toothbrush. Don't smoke it, and use something for lube on the aligning surfaces. I recommend Bullplate because that's what I've been using. Two-cycle mix oil for aircooled engines should work, preferably full synthetic. It only takes a little....works well for the sprue plate screw and on the tops of the blocks and underside of the sprue plate. Apply with a Q-tip.