New to PPing and have a problem.

[JTknives]

well guys i have been here on the forum for a while and have not posted much as i spend most of my time in the chat room bugging ken. but some one mentioned this section of the forum so i had to come check it out. First off i have a WildCat i just finished, its a 50 RazorBack. the 50 Razor back is a 300 rem ultra mag cut off at the neck and loaded with .510 boolits. i have it on a savage 110 action and a K&P 50 bmg barrel.

Well sat was the first test firing. i loaded up 50 test rounds using the lee 500 S&W mould and PP them. being new to paper patching i tried a few different papers. first paper was phone book paper .0025 and then copy paper .0035 then last was some graph paper at .003 thick. the graph and copy paper wrapped the easiest as the phone book paper would rip very easy when wet. problem was that i really did not pay attention to how each shot at the range, i just had a good ol time blasting away lol. after getting home i checked the bore and noticed quite a bit of leading which surprised me. but here is the problem, i don't know if it was just one type of paper that caused the leading or if thy all did. the copy paper wrapped boolits where very large at around .514 - .515 and the graph paper was around .512 with the phone book coming in at about .510- .511.

I did not size any of them as i just figured that the bore would size them for me when fired. i did not find much about sizing when i did my Google search. i just figured that larger meant a tighter seal and less chance of the paper getting blown off. but something is wrong and i don't know where to start. i have gotten some advice to wrap the boolits and then size to .510 which i will try. i have a lee push through sizer that i will open up to .510 and try that. i was looking for the paper after firing but i have a muzzle break so i'm wondering if there would be any to be found. also the round the 50RB is head spaced off the mouth of the cartage like a pistol round. so i wrapped the edge of the paper to the crimp groove on the boolit. the nose ogive starts right at the crimp groove so i did not think the nose would touch the rifling but maybe i was wrong.

Any advice on paper type and a direction to proceed from here would be very appreciated, o and this round will be pushing 450gr plus boolits at over 2000 fps at up to 65,000 psi if that helps. the test loads i tried out where clocked at 1787 fps and should have been at around 30,000 psi. Thanks so much, JT


here are some videos of me shooting it
http://www.youtube.com/watch?v=1QFR7D0rLPQ&NR=1
http://www.youtube.com/watch?v=SpG30RIPKic&NR=1

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[303Guy]

Interesting thread. You have mastered the most important aspect - having fun!:mrgreen: You did things in their correct order. Load some up, try different papers and blast them off!:Fire:

A case that headspaces on the case mouth? That should work well.

I use the throat and bore to size my patched boolits too. The bigger the better, as long as they will chamber properly. I size my boolits (by that I mean I size and shape the molds) so as to produce a touching fit in the throat and a light press fit in an unsized case mouth. That works for large military type throats - I have no idea about other throat styles.

My tests have shown that for a given boolit hardness and a given paper ther is a powder charge that fully disintegrates the patch and below that level, does not.

http://i388.photobucket.com/albums/oo327/303Guy/th_MVC-605F.jpg?t=1304325406Not disintegrating properly but almost there.

Recovered base of patch.
http://i388.photobucket.com/albums/oo327/303Guy/th_MVC-060F.jpg?t=1304325403

Softer alloy and all that's left of the patch is the overhanging skirt.
http://i388.photobucket.com/albums/oo327/303Guy/th_BSAMpatchfragment.jpg?t=1304325401

[CJR]

Welcome to the wonderful world of PPCB! Everyone seems to be in agreement that the bare CB should be sized to bore diameter or 0.0015" greater than bore diameter. Then the PPCB should be sized to groove diameter or a size that just enters a fired case. And then there is the decision on what type paper to use. The paper selection process is almost like the lube selection process for regular cast bullets, i.e. it depends on who you talk to.

What paper I selected was based on what I wanted to achieve, i.e. consistent hi-vel PPCB (2200fps to 3000+ fps). Therefore, I decided to go with the strongest paper recommended by the NRA, i.e. 100% rag ( I use Vellum 100% cotton), to minimize paper failures during load development. I figured that once I got my best loads, I could play around with different papers such as 25% rag or greenbar, etc. My approach seems to be working for me. Before I standardized on Vellum I got lot's of paper failures and severe barrel leading.

Best regards,

CJR

[JTknives]

I got a huge pad of 100% rag cotton vellum today. wow that's some nice paper. I'm going to try and wrap it further down the ogive and push it a bit hotter. is there any use to lubing the paper with alox?

[bbqncigars]

My Sharps would say no to the lube, but that's just MHO. It likes untreated 100% cotton w/o any additives,

[pdawg_shooter]

I use Lee LLA or whatever solid lube I have around at the time. BAC works about perfect for me. I use it to reduce wear in the bore. When shooting to smooth out a rough bore I shoot dry. It cleans up a bore a little quicker that way.

[CJR]

I wet my 100% cotton Vellum PP with roughly a 50% mixture of wood glue + water (a tip Veral Smith gave to me), let dry, spray with dry Teflon spray (NRA recommendation), then coat with LBT Blue (about a match head amount), and then final size to groove diameter. The case is initially sized with no re-expander button in the size die, then a Lyman "M" style die is used to bell the case mouth slightly, and then the PPCB is seated for a nice tight neck. The OAL is adjusted so the PPCB is against the forcing cone. Initially, I just used standard OAL, listed in reloading manuals, and got mediocre groups. Then I discovered my 308Win had a surprising large free-bore, i.e. +0.25". Re-adjusting my OAL, to insure forcing cone fit, tightened my groups at about 2800 fps.

Best regards,

CJR

[JTknives]

Well the problem is solved, i used the new paper and wrapped it further up the ogive and twisted the tail. then when dry i cliped the tail off and loaded as long as i could. put an extra 15grs of powder in it to make it a total of 75grs of 4198. went to the range and got the 450gr boolit going 2300fps. and after about 35 rounds i checked out the bore and 100% lead free. man thats a great feeling to see that. and make is that a stomping round lol. one question is i can not find any paper at all. is it posabul that the paper is staying on the boolit? o and i sized the boolits to .501 and then wet wrapped with e 100 rag cotton vellum and when dry the measured .5105-.511 so perfect lol.

[pdawg_shooter]

If the paper was staying on the bullet you would be lucky to hit the backstop. Paper is cut by the rifling and flys off at the muzzle, at least it does for me. That is why I use pure water, no glue or sticky, when I wrap my bullets.

[CJR]

With all due respect. But in my view, if a hi-vel PP is cut by the rifling and we're talking something like a 308Win, the bullet RPM should be about 194,000 revs/min. Therefore, I find it very improbable that even a wood glued PP (low adhesion) can survive that incredible RPM/centrifugal force, particularly if its been cut by the rifling. The almost Mach 3 air flow over the cut PP sure doesn't help to keep the PP on during its flight over say a 100 yds. If I shot a PPCB into a bucket of sand, I would expect to see some PP adhering to the CB, but not at 100yds after a high RPM/high velocity flight. Low velocity, low RPM PPCB are another story.

Best regards,

CJR

[docone31]

I agree with the rpm theory, but the paper does make it to the backstop at 100yds.
It was at that point, I stopped useing any adhesive whatsoever and let the paper "harden" and then shrink down on the casting.
I actually found that one.

[bbqncigars]

I get confetti at the muzzle, and those boolits are going quite a bit slower (515 grains over 37 of Varget). This can make me a little unpopular with the nearby benches in certain wind conditions. :-)

[303Guy]

... I find it very improbable that even a wood glued PP (low adhesion) can survive that incredible RPM/centrifugal force, particularly if its been cut by the rifling.I'd suggest the RPM plays no role at all. It's the incredible blast of air that'll blow the cut or otherwise patch off! Wood or paper glue won't stick the patch to the boolit but it might make it 'rubbery' or tough. Stick boolit lube on the other hand is quite capable of 'gluing' the patch to the boolit. I've had cig paper survive the catch medium when soaked in molten stick lube. You'd be surprized what follows a boolit in its wake too.

The tail or skirt remnant followed this boolit in the mushroom wake into wet blanket!
http://i388.photobucket.com/albums/oo327/303Guy/PIGGUNintowetblanket.jpg

[CJR]

303 Guy,

Nice photo. Questions:

1. Range where PPCB recovered at?
2. Velocity estimate?
3. Dry/lubed/glued PP?

When I have not been happy with a dried PPCB, I simply remove/tear it with my finger nail. No effort what so ever. Anything spinning at almost 200,000 rpm generates a significant centrifugal force. Likewise, aerodynamic flow/drag/shock wave at almost Mach 3 are significant.

Best regards,

CJR

[303Guy]

Thank you.


Range where PPCB recovered at?
Ummm.... Inside this thing! The muzzle gets pushed down hard on the rubber mouth cone.
http://i388.photobucket.com/albums/oo327/303Guy/MVC-558F_edited-1.jpg My test tube.


Velocity estimate?It's supersonic. Possibly around 1500fps.


Dry/lubed/glued PP?There is a tiny bead of glue applied under the skirt of the second wrap. The patched boolit gets a roll on my case lube pad before seating then the loaded cartridge gets another roll on same pad before firing. So a very light application of STP on the paper. It's not visible to the naked eye but it does make a difference when chambering an oversize PPCB and when seating. It's supposed to leave a protective film in the bore which it seems to do.


Anything spinning at almost 200,000 rpm generates a significant centrifugal force.Yes it does. It's just my suspicion that the supersonic air blast/shock wave on the boolit is a great deal more significant. I've been wrong before, so ....

Just a thought, if air blast/shock wave really is so significant then perhaps a patch that extends forward of the ogive would be advantages simply because it will catch that shockwave and initiate the blowing off that much quicker? I don't know. I have been experimenting with tail-less patches and those seem to work but not sure if there is any advantage. They do look pretty though.

http://i388.photobucket.com/albums/oo327/303Guy/MVC-066F-1.jpg

Would you believe that this ever so slight overhang still followed the boolit into fine sand catch medium? It was still attached to the boolit base!
http://i388.photobucket.com/albums/oo327/303Guy/BSAMPATCH42GR.jpg

Having a test tube sure is fun!:mrgreen:

[CJR]

303 Guy,

Nice setup for testing! Talking about centrifugal force. A classic problem, solved in engineering schools, is to find the maximum rpm at which a flywheel pulls itself apart. Important problem to solve? You bet! That's why drag racers wrap their bell housings with protective blankets so a disintegrating flywheel, at 10,000 or 15,000rpm, does not cut their legs off at the ankles. Likewise, driving a frangible type 22 bullet at too high a velocity, causes the bullet to pull itself apart and never reach the target. Centrifugal force increases by the "square" of the angular rotation. So ROUGHLY speaking, a bullet moving at 3000 fps would have four times more centrifugal force than a bullet traveling at 1500 fps. Likewise, it takes some time after the bullet leaves the muzzle before it lets go or a PP strips off.

Back on the subject of hi-vel PPCB. Yesterday, my youngest son and I had a great range day! After checking my recently updated benchrest, we tried some hi-vl PPCB at 100 yds. My groups are steadily shrinking and I'm down to two promising loads for my 175g. Lyman #311291 PPCB bullet(1/2 gr. weighed lots, CB sized to 0.301", Vellum wrapped with 50% water/wood glue, dried, sprayed with dry film Teflon, LBT blue lubed slightly, and final sized to 0.308" ); 43 gr. of IMR 4064 and 50gr of W760 (NRA recommended powder for the 308W). Pressure appeared normal in my free-bored 308W based on extraction ease and primer look. I still need to mike the base expansions to be sure. Though we had 10 to 20 mph gusty winds to contend with, we got some 1" groups at 100 yds. with pairs of bullets touching in three groups. I've still got a ways to go in load refinements and chroning, but we're slowly getting there and very encouraged with our progress to date.

After shooting, I ran a dry brush down the bore, and the resistance felt the same from chamber to muzzle. Then a dry paper cleaning patch was run down the bore and the bore examined. The bore looked like a mirror! Life is good! What a way to save bore cleaning solvent! Now I've got to cast some more CB, 175 & 150 gr., and see if my load for a LBT 150gr. PPCB can reach/exceed 3000 fps. This art of PPCB is really amazing, and sometimes I find it hard to believe what I'm seeing in my spotting scope! There are no doubts in my mind that my final PPCB loads will equal or exceed the accuracy and velocity of my best match jacketed bullet loads! A truly amazing journey!

Best regards,

CJR

[pdawg_shooter]

Aint it great when it all comes together?

[CJR]

Pdawg Shooter,

Yes it is! From my first attempts that were on the paper, then to all shots on the berm and none on the target, then to shotgun patterns on the target, then to 4"to 6" groups on the target, then to now. My special thanks to you Pdawg, Docone, 303 Guy, etc. who all helped me on this journey. Its been a real blast! The key to successful PPCB is an open exchange/discussion of info/ideas and a steadfast PERSEVERANCE. Oh, and to those starting out in PPCB, if the snickers at the range bother you, keep your "Mickey Mouses"/ear protection on. You will get there one day! Hope springs eternal!

Best regards,

CJR

[pdawg_shooter]

They tend to quit snickering when you funny looking bullets shoot better than their factory rounds. Then you waste time telling them how to make these majic bullets.