Does powder coating mean no lube grooves?

[Jamtrails]

I'm looking to have a custom mould built for subsonic hunting rifle hunting bullets.

If I powder coat will that mean there is no need for lube grooves?

[Walter Laich]

yes,

I've got both and like the ones without the grooves. the bullets seem to come out of the mold better

[oley55]

lube grooves do not hurt powder coating. someday you may want to play with lubes and you won’t have the option. think lubed as dual purpose…

[white eagle]

Some of the high end mono metal cooper bullet makers cut grooves into their bullets
so pick a design you like and you can be sure that the lube grooves will not hurt the
powder coating or performance of your loads

[slim1836]

Just thinking, wouldn't a slick sided boolit, having more surface area, provide more surface area to the rifling, thus leading to better accuracy?

Slim

[mehavey]

Some (most all) of the world cast records are set w/ lubed/grooved bullets.
I would offer that grooves -- or lack of them -- offer no offset one way or the other.

My take?
Grooves give continuous spaces to move material (lead or PC) into as the bullets' are sized.
. . . and the base edges are left effectively pristine.

[oley55]

I'm looking to have a custom mould built for subsonic hunting rifle hunting bullets.

If I powder coat will that mean there is no need for lube grooves?

I’m on a phone so my linking/pasting options are limited. I you go the the “mold, designs” subforum a few sections below this and do an advanced search for “smooth” in the title only. you will get a few good hits to previous discussions with a lot of well thought out opinions.

[Driver man]

Some (most all) of the world cast records are set w/ lubed/grooved bullets.
I would offer that grooves -- or lack of them -- offer no offset one way or the other.

My take?
Grooves give continuous spaces to move material (lead or PC) into as the bullets' are sized.
. . . and the base edges are left effectively pristine.

Where do you find these records. Would be good to see what can be achieved.

[fredj338]

Just thinking, wouldn't a slick sided boolit, having more surface area, provide more surface area to the rifling, thus leading to better accuracy?

Slim
Maybe but i dont see it in my own testing. Granted its my pc grooved bullet v a comm one but accuracy is pretty much the same.

[mehavey]

Wander through
https://forum.castbulletassoc.org/ for latest info/contests/results/discussion
https://castbulletassoc.org/10%20shot%20New%20National%20Records%2006-14-2022.pdf

[Winger Ed.]

Call the folks making the mold. They have years of experience with these things.
I can't imagine they wouldn't give you sound advice or recommend anything that wouldn't do well.
Tell 'em what caliber and what you want it to do, and go with that.

[stubshaft]

I too have both types and the plain sided bullets just jump out of the mold. Just think of it in terms of PC being the equivalent of a paper patched bullet. For accuracy's sake I believe that the winners at the Quigley matches shot mostly PP bullets without grooves. This does NOT mean that I'm going to throw away my grooved molds, but I believe that plain sided bullets will consistently be more accurate to a degree (with all things being equal).

[Mal Paso]

If you remove the grooves you have changed bullet design. Better or worse it's not the same bullet.

Grooves absorb some of the lead displaced by the lands for less distortion of the base.

[Super Sneaky Steve]

The sectional density has also been changed, for better or worse. I can't say one is better than the other but it's not the same.

Recently I've turned my focus to black powder shooting so those groves have come in handy holding lube. If components get any harder to find BP shooting will be the only kind of shooting left.

[mehavey]

FWIW: I also shoot both PP and Grooved/Lubed/(PC'd)
IMHO: - PP/smooth-sided cast bullets are for (1) ease of paper jacket application and (2) minimal "edge" stress
. . . . . . .on the paper when fired -- no other particular ballistic/accuracy effect.
. . . . . .- Powder-coated has neither of those challenges. :popcorn:

[wv109323]

For the same weight boolit, a smooth boolit will be shorter in oal than a grooved boolit. Shorter boolit may mean a slower twist will work. Like splitting frog hair.

[JSnover]

Some of the high end mono metal cooper bullet makers cut grooves into their bullets
so pick a design you like and you can be sure that the lube grooves will not hurt the
powder coating or performance of your loads
They do. It reduces friction by reducing surface contact, since the mono-solid bullet is so much tougher than cast or jacketed. The length of the bearing surface is the same but pressure doesn't spike as high as it might with a smooth-sided copper bullet, all other dimensions being the same.

[bangerjim]

If you got ton of money and time, go out and buy all new NLG molds!!!!!! Waste of time and money.

I have both in many cals & designs, and I feel the NLG design gains nothing at all. Stick with standard grooved molds. That way you can sell them easily to standard non-PC coaters if needed.

Now I have a lot of duplicate designs & cal molds. I have never seen any difference in the accuracy or performance of NLG boolits. And I have been doing this PC thing since 2013.

banger

[charlie b]

I have always liked many smaller grooves rather than one or two larger grooves, and shallow better than deep. When I converted to PC they also have done really well when coated.

The biggest factor for me is gas check or not. For most of my pistols it is no GC. Most rifle bullets are GC (except for my one plinker bullet).