Cast lead lube grooves and ballistics with powdercoating

[Medic]

Hey All,
Quick question, I am interested in casting and polymer coating, I have already sussed out how I would copper coat, but would really like to powder coat and see the differences in how fast I can push rifle projectiles before leading. HOWEVER.

The only 243 moulds for cast lead have a number of lube grooves, which makes me wonder 2 things.
1:Aerodynamics, how much does it disrupt boundry layers and create inaccuracy.
2: Leading, yes it helps catch any blow by and make it usable energy, but could it lead to excess leading?
3: What advantages other than "Holding lube" can you think of, particularly when you are only holding lube which we don't need anymore.

Anyway would be interested in hearing what people have to say. I am really interested in casting some things.

[Wm.Traynor]

Had a look at http://castboolits.gunloads.com ?

[Medic]

Yeah but I feel when I look at the forum I've been smashed in the face with information, almost like I don't know where to begin. Thats ok though, I'll do some research but I'm procrastinating whilst trying to finish assignments atm... blarghg

[Gamerancher]

In my experience, and I shoot thousands of cast bullets a year in my lever guns, even coated bullets shoot better with lube.

There is an argument in black powder circles as to whether paper-patch bullets, which have no lube grooves, shoot better than grooved bullets. I shoot lubed, grooved bullets and can get sub- minute groups at 500m with them. I only know a couple of fella's personally that shoot paper-patch and have spotted for them shooting and they don't seem to be able to get better results with their non-grooved bullets.
Pic: 5 shots @ 500m with 410gr grease grooved bullets.

[Medic]

Thanks for the heads up man, I"ll start with Cast Bullet Engineering molds and then play on my mill, make modifications as I go etc. Gotta start somewhere i suppose

This may interest you..

http://www.geoffrey-kolbe.com/cgi-bin/drag_working.cgi?unit_length=inches&weight_unit=grains&bullet_name=Custom+bullet&re_calculate=yes&diameter=.243&length=.95&nose=.5&meplat=.02&drive_band=.246&base_diameter=.2&angle=15&boat_tail=.2&secant_radius=&weight=94&density=11.4

[Gamerancher]

I've cast for 7mm and .303, I shoot them at velocities around 2000 f/s with gas-checks. Both bullets have only 1 lube groove. I have a CBE mold for .38/55, they do make good molds.
Any lead that runs on the barrel can cause leading, hence the commercial ones tend to be coated. It also hides a multitude of faults. Lead bullets need some type of lube, think .22 rimfire. The coatings are supposed to negate the need to lube but as I have said, I get better results lubing even those.
There are a number of things that will cause leading. How smooth the bore is. Hardness of lead. Speed of bullet. Bullet fit in barrel. Inadequate lube/coating. Bullet design. Finding what works in your own circumstances can be a bit of trial and error, there is no "magic" formula. But that just means you get to shoot more.

[RDobber]

Yeah but I feel when I look at the forum I've been smashed in the face with information, almost like I don't know where to begin.

Ha ha.

It can be like that.

To reload ammunition... Do these 90 things perfectly first time

[Xerox]

Pic: 5 shots @ 500m with 410gr grease grooved bullets.

Is that with our without patching?

(And good shooting )

[Gamerancher]

When you say patching, do you mean cleaning between shots? Answer is no, used blow-tube.