Remove Lube Grooves and Gas Check Shanks

[FabMan]

Was wondering if anyone has a "best way" to remove these from
both steel and aluminum molds? Adjustable Reamers?
I have access to a lathe and Bridgeport mill with rotary table. Thanks

[gzig5]

Lathe would be my first choice though a BP with a boring head might be quicker to setup. In the lathe dial the hole in on the four-jaw chuck and use a stiff small boring bar to remove what you want. In the BP you would center on the hole and dial the boring head out iteratively to get to the diameter you want. Lathe is more flexible IMO because you can go up in and adjust band diameters individually. I don't think a rotary table brings anything to the party unless you don't have a boring head.

[upnorthwis]

Just out of curiosity, why do you want to remove them?

[jhunt1981]

I would agree with gzig5. A lathe, a 4 jaw, and a small boring bar is the way I would go. Assuming I was going to do it, that is.

[FabMan]

I’m trying to get away from gas checks and try just powder coating at higher velocities.
I would like to try on multiple cavity molds(6-8) and use a reamer for the aluminum molds.
If I could center it in a mill and bring it down in the cavity that might work.

[Irascible]

http://www.hollowpointmold.com Erik will modify your mold to your needs. Nice guy. Perfect work. Quick turn around.

[FabMan]

Thanks Irascible,
I have around nine 6-8 cavity molds to do and having it done for 100.00 per mold wont work.
I'm sure Erik does great work but I have the equipment to get this done. I'm just seeing if there is a shortcut
or someone has done this without indicating each cavity to mill it out.

[Dan Cash]

Less trouble and expense to order a new mould cut to your spec from Accurate.

[FabMan]

Got that right Dan! I’m going to play around with this on the mill.
If I come up with a short cut I will let you all know.

[jhunt1981]

If the cavity spacing is the same for each of the 6 cavity and each of the 8 cavity molds, you could whip up a jig with a few stops and just walk the mold down the jig to hit each cavity. Then at least you would only have to indicate it once.

[mdi]

Just my thinking, but it isn't necessary to remove lube grooves from a bullet for PCing. I have only been PCing for a few years and I have purchased "no groove" PCed bullets and I have seen no difference in performance. I have loaded them to the same velocities, and during experimentation velocities upwards near max powder charges. I have removed gas check shanks and bevel bases on a couple molds and it was easily done on a drill press using a drill...

[mehavey]

... it isn't necessary to remove lube grooves from a bullet for PCing.^^^^ THIS ^^^^
Just take off the GC protrusion in the cavity base(s).
Don't mess with anything further up the shank.

[white eagle]

manufactures go to great length's to cut grooves into monometal
bullets,similar to lube grooves,to reduce pressure and bearing surface
seems to me that by PCing the boolit you are accomplishing the same
unless you just want to play with a mill or lathe you may want to leave well enough alone

[JonB_in_Glencoe]

Just my thinking, but it isn't necessary to remove lube grooves from a bullet for PCing. I have only been PCing for a few years and I have purchased "no groove" PCed bullets and I have seen no difference in performance. I have loaded them to the same velocities, and during experimentation velocities upwards near max powder charges. I have removed gas check shanks and bevel bases on a couple molds and it was easily done on a drill press using a drill...

Adding my 2¢ about leaving the lube grooves alone.
A lube groove gives the alloy somewhere to go as a boolit is being squeezed down, while inside the barrel. If there is no lube grooves, the alloy will move toward the top or the bottom of the boolit. If it moves to the bottom, then the bottom will likely become less perfect (distorted) and you may see a decline in accuracy. This is especially true with Rifle boolits.
Now, if you are shooting pistol boolits at 7 rds, you'll be just fine with boolits without lube grooves ;)

[FabMan]

I’m not too worried about the lube grooves, it’s the gas check shank that supposedly affects rifle range accuracy. I could see how it could do that as my bases are not perfect by any stretch.
Stock Drill sizes are not going to work for me. And I don’t see how you can get a presentable finish without polishing or using a reamer.

[slide]

Powder coat will not replace a gas check at higher velocities.

[mehavey]

Powder coat will not replace a gas check at higher velocities.PC does, however, significantly raise the pressures & velocities that plain-based/soft-alloyed bullets will stand being pushed.

Again, note:http://castboolits.gunloads.com/showthread.php?409893-Pure-Lead-amp-PC&p=5001471&viewfull=1#post5001471

[garandsrus]

If you are modifying multiple cavities, the mill is the way to go. Indicate the part in for the first cavity and then just go down the line moving the X axis. The holes will have a consistent spacing, because that’s how the mold was made. The spacing is probably in MM.

[Charlie Horse]

I have removed gas check shanks and bevel bases on a couple molds and it was easily done on a drill press using a drill...

I have a single cavity, 170 grain Lee mold, 30 caliber that I'd like to try this on. The mold came in a trade and I've never used it. Got another. If I wreck it, no big deal. Going to use a Harbor Freight drill press no less.

Hold my beer.....

[charlie b]

I had a Lee mold I did that to. I had an old tapered reamer I modified to cut it. The base had a small flare to it but a trip through the sizer fixed it. Shot as well as it did with GC's at lower vel.

I agree with others that you keep the lube grooves. I also believe that the lead needs a place to go when it engraves the rifling.

[charlie b]

I had a Lee mold I did that to. Shot as well as it did with GC's at lower vel.

I agree with others that you keep the lube grooves. I also believe that the lead needs a place to go when it engraves the rifling.

[mehavey]

^^^^ this ^^^^

[Dusty Bannister]

With the belief that the plain based velocity limits will remain the same even with powder coating, it would seem that shooting a bullet cast in a gas check mold would serve the same as shooting a boat tailed bullet. The loss of value in modifying a multi-cavity mold should be compared with buying the mold you want and selling the original but undamaged mold. I just do not see the effort being worth the labor or risk of damage to a good mold. But, your dice, roll em and see what it costs you if it goes wrong.

[charlie b]

All depends on how accurate you want them to be.