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Marlin Junky
02-21-2009, 09:13 PM
I'm patching RCBS 30-180FN that are .308" in diameter and 1.045" in length. I figured the patch width at 1.96" but not real sure how long to make them. I want to have enough material to make a nice tail and cover the forward driving band but I'm not sure how far up the nose the leading edge of the patch should be. The noses, which measure .3000"-.3005", are not too snug in the '06's bore and I'll be final sizing the patched bullet of 10.5 BHN alloy with two wraps of .002" tracing paper first in a .3115" Lee PT and then in a .309" PT die.

MJ

docone31
02-21-2009, 10:13 PM
I gave you the dimensions.
I will give them again. These are for patching over .308.
Cut the strips 1".
Make the patch 2 3/16" with 45* at each end.
There is a little overlap with this size. I have not found it to be an issue.
I took a piece of vynl Venetian blind the cats cracked off the window. I use this as a template.
I lay the strip in the template, and with scissors cut.
I make about 200 at a time, and spend the evening wrapping.

pdawg_shooter
02-23-2009, 09:23 AM
Take the diameter of the bullet times 3.124159 and multiply by the number of wraps. This will be a good place to start. Adjust from there.

docone31
02-24-2009, 10:53 AM
Marlin, how you coming with the patching?
We be waiting to hear.

Marlin Junky
02-24-2009, 03:11 PM
Marlin, how you coming with the patching?
We be waiting to hear.

I'm still getting my tools and paper together. I made a patching board ala Paul Matthews and I'm waiting for the varnish to dry. I noticed that the paper I selected pretty much disappears on the board when it's wet and takes a little effort to line up so the patch is rolled on square. I was wondering if it's an OK idea to put a couple drops of green or blue food color in the patching solution so the patch is more opaque and therefore easier to handle. As far as paper is concerned the only thing I've been able to find is two brands of 25# tracing paper at the local art supply stores. They both mike about .002 or a tiny bit under (I've only checked the thickness on my digital caliper that reads .0005" at best). I also need to pick up a straight edge and some Xacto knife blades so I can cut the patches. It all sounds like a bit of effort but once I'm geared up things should go just as smoothly as working with grooved boolits and there's probably no need for heat treating with the patched boolits. I just hope the paper I've found will work satisfactorily.

MJ

docone31
02-24-2009, 03:16 PM
I got a paper cutter, and I use a Venetian blind piece for a template.
I like the KISS approach.
You, however, will have more versatility with doing it the traditional way.
I do not think food dye will have any effect on your patches. Might help the paper bond better, who knows?
I am looking forward to hearing your final results, whether successful or not quite.
They walked me through it.

scrapcan
02-24-2009, 03:49 PM
circumfrence of a circle (length around the circle) = pi * diameter = 3.14159 * diameter

pdawg did what I do alot and let the fingers get you an extra character when typing.

Marlin Junky
02-24-2009, 04:22 PM
circumfrence of a circle (length around the circle) = pi * diameter = 3.14159 * diameter

I usually use the first fifteen digits: 3.14159265358979. :mrgreen:

MJ

Marlin Junky
02-24-2009, 04:24 PM
I do not think food dye will have any effect on your patches. Might help the paper bond better, who knows?


I'll ask the guy that wrote Paper 101.

MJ

scrapcan
02-24-2009, 06:31 PM
MJ,

Me too for the normal calculations (actual to 19, but who cares). I think we could use 3 SD based on our measurement method of eights and sixtenths in this thread.

and keep up the humor.

rhead
02-24-2009, 06:39 PM
:-D I thought that pdawg had figured out how much shorter the paper needed to be to allow for the stretch. [smilie=1:Splain it to them Pdawg.

Marlin Junky
02-25-2009, 06:56 AM
Update:

All the tracing papers I have tried are too weak after wetting to hold up to twisting a tail. I'm going to look for 25% cotton content paper (I guess that would be onion skin) on the internet and in the mean time, keep shooting grooved/lubed boolits until I can find better suited paper.

MJ

pdawg_shooter
02-25-2009, 09:22 AM
Diameter times 3.14159 is a starting place, not a finish size. Because there is 2 wraps, the second being longer then the first, you will be real close. Adjust up or down as needed. If you change paper you will have to adjust again, but you will have a good starting place.

docone31
02-25-2009, 10:35 AM
MJ, there are several factors that make twisting the tail a potential tear off.
First, sharp edges on the base of the casting. I routinely take my fingernail and smooth the bottom.
Second, TOO MUCH twist pressure. I ran into that several times. I finally went with a gentle twist, almost smoothing the tail as I went.
Try notebook paper. It sizes just as easily.
Remember, we are dealing with wet paper here. Tender touch!
I suspect, my use of the cigarette roller has made patching these rounds simple. The down side, if I ever are in a position to need to roll without one, I just might be out of ammo.
When I twist my tails, I almost massage them into a twist.
Hang in there, you will get there!

Marlin Junky
02-25-2009, 03:32 PM
docone31,

I was able to get a decent patched bullet by not actually twisting the tail while wet but by more or less crimping the tail in place and waiting for the patch to dry before twisting. Now I'm trying to decide how much of the tail to clip off.

Somewhere along the road I heard (I think is was from V. Smith) that a good patching solution incorporated about 10% Elmer's Glue in water. Have you ever tried this?

MJ

docone31
02-25-2009, 04:49 PM
I read on those formulas also.
Nix on the glue, eggwhites. You really do not need it, and if it sticks to the casting after being fired, you will wish you did not.
Tight wraps, let dry.
I am not sure tails matter a great deal, as long as the paper is over the base. When I size my patches, the base of the patch gets real flat on the base of the casting.

Marlin Junky
02-25-2009, 08:00 PM
Nix on the glue, eggwhites.

How much eggwhite? For example, one eggwhite in a pint of tap water, well shaken, or something like that?

MJ

docone31
02-25-2009, 08:27 PM
MJ, just plain old water, or new water from an R/O filter. You can even combine hydrogen, and oxygen.
Nothing, nada, zip on additives.
It works well enough.

Marlin Junky
02-25-2009, 09:36 PM
docone31,

So you're saying no Elmer's or eggwhites? I thought you meant use an eggwhite instead of Elmer's. That's why I asked how much eggwhite per volume of water.

If I wanted to try eggwhites, would one eggwhite per pint of water be about right?

MJ

docone31
02-25-2009, 09:49 PM
I really have no clue how much eggwhite might work. Trust me, I use plain water. It works beyond my wildest expectations.
The real trick, make sure you start with the wrap on the nose, not base like my first 100 were.
They could be picked apart.
The nose start could not be picked apart under ordinary circumstances.
I doubt, you will ever need eggwhites wrapping those loads.

montana_charlie
02-26-2009, 12:13 PM
If I wanted to try eggwhites, would one eggwhite per pint of water be about right?
If you insist on using egg on your patches, you are required to use bacon drippin's in your grease cookie.

Then, when others smell your smoke...thay all come to your bench for some breakfast.
CM

Marlin Junky
02-26-2009, 06:57 PM
If you insist on using egg on your patches, you are required to use bacon drippin's in your grease cookie.

Then, when others smell your smoke...thay all come to your bench for some breakfast.
CM

How 'bout I use doughnut crumbs for case filler? :-D

MJ

Marlin Junky
02-26-2009, 07:13 PM
Docone31,

When the patched round is chambered, should I feel a little resistance on the bolt handle? I shot the old 336 in 30-30 today but I also brought my M70 '06 and one round of PP'd ammo to the range because I wanted to see what would happen before I take the time to load a batch of '06 PP ammo for next week. The '06 went off and the round clocked 2194fps (somewhat faster than it's grooved/greased counterpart) and it actually printed on the target at 100 yards, a mere 3.375" from the aiming point. I pulled the bolt, looked at the case neck and chamber and all seemed copacetic. :)

BTW, for lube I used a light coat of JPW just before running the bullet through my .311 push-through die and also just before running through the .309". This process actually created a patched bullet nearly .310" as measures on my 1" micrometer so I lightly lubed the bullet again with JPW and ran it through the .309" die a second time which yielded a bullet nearer .3095".

MJ

docone31
02-26-2009, 07:19 PM
You might try bumping up the load a bit. Patched loads are capable of much more speed.
Feels good though, doesn't it?
Glad I could help, even the little bit I did. I got helped here.
Made it possible.
You have just touched the possibilities.
I don't feel any resistance in my bolts. I do not have them out that far.

Marlin Junky
02-26-2009, 09:48 PM
You might try bumping up the load a bit. Patched loads are capable of much more speed.

That's why I'm gearing up for PP bullets. I just wanted to try the powder charge where accuracy stopped with the RCBS 30-180FN in grooved/lubed form. The same round loaded with grooved RCBS 30-180FN at 195 grains (bare weight) clocks 2150* fps and accuracy lasts about 10 rounds even with the best lubes.


Feels good though, doesn't it? Glad I could help, even the little bit I did.
Yes, thank you. Next Thursday is group shooting day.


I don't feel any resistance in my bolts. I do not have them out that far.

I lapped the paper over the leading band of RCBS 30-180FN a hair or two and seated the bullet .015" deeper than I would have normally seated a grooved 30-180FN. Should I continue to lap the leading edge of the paper over the first driving band or just bring the patch up to the edge of the first driving band?

MJ

Note to above *: In all fairness, the 40 fps gain may be due to the elimination of the 4.3 grain gas check.

docone31
02-26-2009, 10:07 PM
I go pretty far up the nose with my patches. I try to not go past where the ogive starts to get smaller in diameter though.
I played around with that.
It was just harder to set the patch over the crimp groove on my castings than just set the casting on the patch and roll it up.
I have not found a difference in performance between low patching, or high patching. Just convience.
Essentially, I set the boolitt to where it shows on the case diagram. I like to have meat in the neck. You never know when you have to move around quickly and only have patches handy.
I use the Lee FCD die. I do not crimp the case, but run it to tighten on the patch so it has resistance.

pdawg_shooter
02-27-2009, 06:23 PM
That's why I'm gearing up for PP bullets. I just wanted to try the powder charge where accuracy stopped with the RCBS 30-180FN in grooved/lubed form. The same round loaded with grooved RCBS 30-180FN at 195 grains (bare weight) clocks 2150* fps and accuracy lasts about 10 rounds even with the best lubes.


Yes, thank you. Next Thursday is group shooting day.



I lapped the paper over the leading band of RCBS 30-180FN a hair or two and seated the bullet .015" deeper than I would have normally seated a grooved 30-180FN. Should I continue to lap the leading edge of the paper over the first driving band or just bring the patch up to the edge of the first driving band?

MJ

Note to above *: In all fairness, the 40 fps gain may be due to the elimination of the 4.3 grain gas check.

For best accuracy seat the bullets OUT till your paper engraves the rifling. Patch with heavy enough paper to fill the throat if possible. I load my 06 in unsized brass.