PDA

View Full Version : How much tolerance in boolit core for paper patching?



rockydoc
03-07-2019, 04:28 PM
It has been stated that the boolit core to paper patch should be .001" to .0015" over BORE diameter. What would happen if it were as much as .002" to .0025"? That is still less than groove diameter, the lands should be able to cut through the paper. Would this cause leading? Not leave enough room for paper?
Using a boolit .002" over bore might mean the difference in being able to use the same mold that I already have for lubed boolits rather than having to buy a dedicated mold for paper patching only.

I am obviously new to paper patching. I am having a hard time sizing a .285 boolit down to .278". Lee molds are certainly cheap enough, I have ordered a C277-135RF but if it does indeed cast .277 it will be SMALLER than bore. I assume that wouldn't work because it wouldn't cut the paper into shreds at the muzzle. I am aware this mold could be beagled, but still, that is a lot more work to do.

I have other calibers I will want to paper patch and I am not happy at the prospect of having to buy a new stable of molds. And a lot of beagling to do.

John McCorkle
03-07-2019, 04:48 PM
May not allow you to size or have a final bullet diameter (after wrap) to fit in throat of chamber or in brass neck. Guess it depends on paper thickness and final sizing diameter to fit the throat.

Sent from my Moto G Play using Tapatalk

barrabruce
03-11-2019, 10:37 AM
Have a go and see what happens.
The thou over bore is a rule of thumb.
If you rap and are a few thou I’ve groove and size back down to a thou over groove.
In wrap check your core diameter.
Some times the paper will be that tight it I’ll size core down smaller.

Try everything and see what your gun likes.
Sized /unsized cases.
Groove to what ever size your fired case will take and you can seat in the neck still.
A few thou oversized could be just the ticket after the throat wear a bit.

edwin41
03-11-2019, 01:21 PM
I stopped sizing my cores for the 6.5x55 mm cartridge long time ago..
My cores Come out the mold like. 264, then i wrap them twice and then i run them through my
.264 lubrizer.
The paperpatch is real thight now!

bmortell
03-11-2019, 01:57 PM
ive never sized down any cores. in my 30-06 and 300 I cast at 308 diameter then I either wrap with tracing paper, dry, wipe LLA, or shake powder coat and gas check. then I run them both through same sizer at approx .3097, both shoot equally well, about as good as id expect for the load, speed, and 10 twist. and I find bits of paper in front of muzzle as if its working good.