Mold modify

[Wireman134]

Hello, just wondering if anyone has modded a gas checked mold to a plain base? I'm thinking of doing this to my C452-300-RF Lee mold since I don't plan on using checks with this boolit.

[cbrick]

Yep, pretty common actually. I've had several done myself by Erik @ Hollow Point Mold Service (http://www.hollowpointmold.com/) and I highly recommend him.

Rick

[Slow Elk 45/70]

I have had this done with steel molds, haven't tried any aluminum, as stated check with Eric or Buckshot, they can help....

[Catshooter]

Yes, I've done three or four. Milled off the top of the mould until the gas check was gone. Worked wonderfully.

If you search for my threads, you'll see the results of some of them.


Cat

[Buckshot]

http://www.fototime.com/9343DBFA31116FB/standard.jpg

...........You can have the blocks flycut (as above) to remove bevel bases or GC shanks, which gives you a lighter boolit. Or they can have the mentioned features lathe bored to remove them and this gives you a slug of the same length but going slightly heavier.

.............Buckshot

[Lloyd Smale]

Ive done it to a few molds but theyve never been accurate bullets afterward. My suggestion is to either use gas checks or buy a mold with a bullet that was designed to be a plain base.

[RobS]

Another option is to simply not gas check that particular bullet. I've seen many people who have done it and I have too. At low to mild velocities and pressures this bullet shot well enough (2-3" at 35 yards) for my uses. I will tell you this though the bullet does like to be run hard for stabilization and to achieve really good accuracy. This is probably why it was designed with a GC so the velocities could be obtained with less efforts(extra attention given to alloy hardness, powder selection etc). Lloyd Smale has sound advise and it all depends on what will work for you.

[jmsj]

Hello,
I've got some questions for those that have modified this C452-300-F mold.
If you fly cut the gas check step out, what was the finished weight?

If you reamed the gas check step out, what was the finished weight?

Without a gas check, is the lube groove in this bullet large enough to push it hard enough to stabilize this large bullet without leading ?

[Edubya]

Hello, just wondering if anyone has modded a gas checked mold to a plain base? I'm thinking of doing this to my C452-300-RF Lee mold since I don't plan on using checks with this boolit.

I'm not replying from experience, but it seems to me that reaming would be the first thing to try. If that did not produce the results that I wanted, I could still flycut.
EW

[Wireman134]

Reaming or drilling the base of the mold is what I would do. I want to keep the weight of the boolit. If this mod is done my concern is the lack of a lube groove near the base, as removing the check shank leaves very little if any groove in that area. I've seen some were this done to a boolit and the last band is super long. If the Lee design started its groves closer to the nose and added a real grove near the base before the check shank, this modification would be a easier task that would retain a lube grove near the base. I've shot some of these without checks but haven't noticed any leading or accuracy issues, this will most likely determine my actions. Fly cutting is really not a option, I want a 300gr. boolit, but most molds are checked.

[dubber123]

The copy I had of that mould cast at 320+ grains. That would leave some leeway for the flycutting option. I don't know how much flycutting would remove, or if your mould casts as heavy as mine.

[Wayne Smith]

Couldn't you remove just part of the GC shank, leaving enough for a lube grove? Not very deep, but there would be some.

[Wireman134]

That's a possibility. But will leave only about a .060" band at the base with a shallow .040" lube grove. I'm thinking a step bit would work in 29/64" but tough to find. A standard 29/64" drill bit? Oh but wait, a 44 case is .456" dia., I have one of those and it measures .454". I did it, used a Lee case chamfer tool to start, then the 29/64ths drill bit by hand, followed by that 44 case I cut teeth in with my Dremel tool cutting wheel. Used a brass bushing as a pilot, dropped into the mold clamped in my vise. Affixed a screw as a shaft to chuck in my battery drill and used some Brasso as cutting fluid, the closest I have to a lapping compound. The brass case doesn't cut to aggressive but it does remove the aluminum gently. I think I can achieve a .060" base band while maintaining a shallow .040" lube grove. I casted a few, and sized to .452". I think I'll work on this a little more to get a wider band, looks good so far.:coffee:

Update: Used 44 case tool and widened last band to .065". Cast mix is approx. 97Pb/1.5Sn/1.5Sb, Bhn 15 after water dropped for 18 hours (lower pic). I think I'll pan lube then dip base in Xlox to fill lower lube grove.

[Rem700]

I recently had Buckshot remove the GC shank on a 430-310RF mold.
Casting straight WW the boolits drop at 268gr.
I am TL with 45/45/10 formula and have no leading issues at 1500fps useing a Marlin 1894 micro groove barrel. Accuracy has been good at 50yds, Sorry I havnt been able to do any testing at longer distances which will have to waite until spring.

[geargnasher]

Wireman: I have done exactly what you're doing with the same mould you have, it works great if you are VERY careful cutting the base out.

I too was concerned about the narrow base band, but, like 44man has mentioned, it doesn't really matter that much unless you're shooting it in a .454 Casull, and you'd be using a gascheck for that anyway.

The trick is use a 29/64" bit in a good drill press, mount the mould in a drill vise, square the deck, and turn the chuck by HAND. Just carve it out gently, you'll be fine, just get the bottom of your cut even with no bumps.

It is important to lap the base of the mould after doing this, it ensures concentricity and polishes any burrs/grooves left from cutting. It also brings the base up to size, as a 29/64ths hole is about .453" but makes for about a .4515" ase band with WW alloy.

These boolits shoot great, the only reason I chose to drill out the GC shank was to gain a lube groove and make the boolits cleaner to lube/size, no lube in the GC recess.

For the record, doing this added exactly five grains to the boolit weight, and the extra lube groove really isn't necessary, the boolit will work just fine with one, they are large enough on this design, even with rifles.

Hope this helps,

Gear

[Wireman134]

Thanks, geargnasher, for the encouragement. That 44 case I made a hole saw out of seems to do a fine job of lapping. I might be doing a little more with this tool to get the base band too full diameter at the grove transition. My base as cast is about .455"-.460" and sizes down to .452" just fine in the Lee sizer. I'd like that bottom band to be a little more square at the transition into the grove. Nice to no I got a bigger hammer now with that extra 5 grains. [smilie=w: If I might ask what did this boolit weight prior to the mod.