Paper Jacket

[justindad]

So I’m calling it a jacket, because it is not a patch in the normal sense. I am trying to cover the lube on a .357SIG, because a part of the lube groove rests inside the case, touching powder. I’m not covering the entire lube groove, in case the paper does not come off when fired. Ideally, the barrel throat would rip the paper off. This boolit is sized for typical groove diameter, and the paper is a single layer of cigarette paper that adds 0.0015” to the diameter.
Any thoughts or recommendations before I go too far?
292205

[Winger Ed.]

Experimenting around is good, and evolves the sport and industry.
However:
If you're using a rather hard lube, I think you have a solution for a problem that doesn't really exist.

Check out the cast rifle boolits in .30 cal. Nothing special about .30, it's just super common and well developed.
Almost all of the boolits loaded for them will have a few lube grooves down inside the case past the neck, and it isn't an issue.

[GregLaROCHE]

If you are going to do that, why not consider a complete paper patch and forget about the lube?

[justindad]

I’m just trying to make do with what I have. I’m using a soft & wet Felix lube, and I don’t have a way to get my boolits down to bore diameter. My ultimate plan for the SIG boolits is polymer coating, but I’m really dragging my feet on bringing plastic into the game.

[Nobade]

Most likely that patch will tear off when the bullet engages the rifling and the accuracy will be rather poor.

[country gent]

I can see feeding and functioning issues as that paper jacket is likely to leave a paper ring in the throat when fired.

I use cigarette papers as shims and for cleaning measuring faces on mikes and a for setting cutter clearances. most measure in the .0012-.0015 range for thickness so one wrap would be double that added to dia of the bullet. As an example O PP a 443 45 caliber rifle bullet with 2 wraps of seth cole paper at roughly .0017 thickness. This is a tight wrap. bullets are a final dia of .450 -.451 ( bore riding)

Lees liquid alox or water soluble sizing wax applied in a light coat should dry and make a light shell to contain the soft lube. Or possibly a light dusting of motor mica after sizing.

[GregLaROCHE]

I’m just trying to make do with what I have. I’m using a soft & wet Felix lube, and I don’t have a way to get my boolits down to bore diameter. My ultimate plan for the SIG boolits is polymer coating, but I’m really dragging my feet on bringing plastic into the game.

Don’t hesitate. Start powder coating. You'll be glad you did. It works really well.

[Alferd Packer]

So I’m calling it a jacket, because it is not a patch in the normal sense. I am trying to cover the lube on a .357SIG, because a part of the lube groove rests inside the case, touching powder. I’m not covering the entire lube groove, in case the paper does not come off when fired. Ideally, the barrel throat would rip the paper off. This boolit is sized for typical groove diameter, and the paper is a single layer of cigarette paper that adds 0.0015” to the diameter.
Any thoughts or recommendations before I go too far?
292205
Another way to squeeze down a bullet is to get a Hornady bullet puller handle and the right size collet to fit your bullet.
When you use this device to pull bullet, it put the squeeze on to grip the bullet .
If you are not careful, too much squeeze reduces the size of the bullet quite a bit.

I have used this to reduce the size of.229 bullets to .224.
Also some .450 case necks
to .430.
I have squeezed others over the years from 8mm to .308.
.33 to .30 caliber.
You will need more than one collet to overlap sizes.
You can do the same with a set of collects from a machine shop, but a little pricey.
You can squeeze the slugs with the paper wrapping on them and go from there.
It's all experimental anyway.
Maybe you will add a new wrinkle to this ongoing loading and shooting thing.
Good Luck
.