Tail-less Patching

[303Guy]

I have tried before but the question arose again so I am going to try it again. It seemed to work before but It required either wet patching or a dab of glue inder the trailing edge corner which was right on the boolit shank. Well, this time I am applying a bead of glue under the trailing edge of the top wrap. Test tube tests show no issues. The patch disappears and there is no leading in the bore nor signs of patch failure on the boolit tail end.

http://i388.photobucket.com/albums/oo327/303Guy/TAILLESSPATCH005.jpg
http://i388.photobucket.com/albums/oo327/303Guy/shotskirttails.jpg
http://i388.photobucket.com/albums/oo327/303Guy/shotskirttails2.jpg

The boolit surface has that strange appearance with both tail and tail-less. It does look suspiciously like 'micro gas cutting' but it could also be from passing through a whole bunch of catch rags. I wouldn't expect any gas leak with this boolit. It is a tight fit.

The boolit gets sized in a push-through die and is quite firm to size. It gets knurled before patching and that patch does not move on the boolit. It is firm seating fit in the case mouth and if that does not slip the patch then nothing will.

The load is 33gr AR2208/Varget under a 205gr boolit fired in my pig gun which has a rough bore.

Range tests to follow.

[geargnasher]

DrB and I were discussing this too, probably the same conversation. One of my current projects is to try making a boat-tailed PPCB, with the jacket just being a band of paper around the midsection and tapering just over the ogive a bit on both ends.

I took one of my Accurate 30-160P boolits, chucked it in my vertical plunge mill (drill press!) gently and turned the base to a nice BT profile, then patched it with two wraps of 100% cotton vellum. I didn't get to shoot it tonight due to a long continuing-education class after work, maybe tomorrow. I'm going to use PSB as filler since it's been working so far, I think that filler is going to be key to sucess with BT designs, if they can be made to work at all. My principle concern was whether or not a flush patch would protect the boolit from gas-cutting or not at high pressure, your initial results are encouraging.

Gear

[303Guy]

There was an article on boat tail cast. It was found that a wax cup to support the tail did the trick. Without the protective cup the base got distorted. Along that same line, the PSB might just be the answer.

Another possibility would be to make the patch to end flush with the boolit base but let it hang free then pour molten wax into the gap to form the 'cup'.

(Yes, I have thought of boat tail PPCB's. [smilie=1: I think it's a great idea!)

[geargnasher]

Interesting thing about the wax, I guess if you have a good-fitting patch and no gas leakage the hydraulic pressure of the wax on the BT base would be uniform and preserve the shape. I was thinking about a two-cavity mould, one to cast boolits with that would have a flat nose and hollow point pin and a boat-tail base, and a cavity right next to it cut about .001" larger, with a plain base and nose cavity cut into it with a sprue hole leading to the nose. Once the boolits were cast, then they would be placed in the cool mould in the other cavity, where the base could be formed with a hot-glue gun and the ballistic tip injected with a glue gun at the same time. After removal from the mould, the whole thing would be patched as normal with the tail twisted and the leading edge of the patch going just past the ogive. The patch would prevent the hot-glue base cup from contacting the rifling and smearing.

Possible issues I can foresee with the design is the base trying to spread under pressure and venting the HP cavity in the nose while forming it might make it tough to get the glue down in the cavity completely. Just musing here....this might be totally impractical. The PSB might be all it takes to protect the base just by itself, and if it works would allow the BT part to be seated below the neck slightly, allowing heavier boolits to be used.

Gear

Gear

[Lead pot]

Been down that trail with this rebated boat tail hp bullet and found no benefit in it.
There is a better way to protect the base from getting deformed then wax.
http://i704.photobucket.com/albums/ww43/Kurtalt/IMG_0264_1.jpg
http://i704.photobucket.com/albums/ww43/Kurtalt/IMG_0265-1.jpg
http://i704.photobucket.com/albums/ww43/Kurtalt/IMG_0296-2.jpg

[303Guy]

Are you saying the hollow base balances the pressure applied and prevents deformation?

[Lead pot]

No, Wheat flour is the magic formula

[geargnasher]

That makes sense. Wheat flour will make one heck of a hard plug under high pressure.

Gear

[longbow]

You might want to read this:

http://www.public.iastate.edu/~jessie/PPB/PPB_files/Page1187.htm

I tried some 316299's without gas check over COW filler and recovered a boolit that looked more like a boattail boolit than a gas check shank. I think heat treating may be in order to avoid base distortion.

Lead Pot's boolit looks good so maybe the wheat flour packs up tight and hard minimizing distortion but COW certainly didn't for me. My alloy was ACWW so not real hard.

Slow burning smokeless powder may also help avoid distortion through gentler acceleration.

Longbow

[303Guy]

Thanks longbow. I think this may what I was thinking of. Similar anyway.
http://i388.photobucket.com/albums/oo327/303Guy/image1330.jpg

Lead pot
How do you load those? That's not a fast load or the boolit wouldn't be recoverable - I think.

It is an interesting boolit shape. With the idea of increasing boolit weight with a boat tail or rebated boat tail the rebated portion would need to protrude into the case and I'm scared of fillers that can compress and raise pressure. But in reality, flour is full of air so it should be able to flow and compact around the rebated boat tail. I've had flour lying around for years and it hasn't compacted or grown any silk moths or the like. Not like whole grain flour - the bugs love it! (Maybe why we should too:rolleyes:).

[pdawg_shooter]

I will stick to the twisted tail to protect the bullet base. Been working for me for over 40 years now. No filler needed. I choose a powder that gives me near as possible to 100% load density.

[Lead pot]

Using flour in a bottle neck case is not advisable if it gets below the heck into the shoulder. The chances would be to great for a pressure spike.
That bullet was shot using a straight walled case loaded with black powder at around 1260 fps. I dont mess with smokeless powder.
I had one card over the powder a 1/8" lube wad one card over the lube, two Lee 7CC powder dippers of flour under the bullet. The patch was just past the rebate. The alloy was 1/20 T/L bullet was patched .001 under bore diameter.

[geargnasher]

Well no wonder it was "no advantage" to you, Lead Pot, at barely supersonic BP velocities there isn't much to be gained from the effort. What I'm talking about is pushing near 3K fps with a medium-weight boolit in .30 caliber with slow-burning smokeless powder. I've also been doing a lot of work with compacting fillers lately, and if you keep your wits about you and experiment carefully, it works fine. Get stupid with compacting fillers and Darwin will get you.

Gear

[Lead pot]

Gear I never said that it didn't work, it shot good I just never seen any benefit going through all that work making and loading it with no gain in accuracy over the conventional bullets.

[303Guy]

That bullet was shot using a straight walled case ...That's what I was worried about!:mrgreen:

Still, the idea shall be remembered. One never knows when it might be applied.

I'm wondering what would happen if one were to patch over a thick wax or card or something wad for a flat base boolit and seat that protruding into the case? I guess I'll just have to try it and find out! I still like the idea of extending the boolit into the case for extra weight. But maybe 205gr at 1800 fps is actually enough already (assuming I can get that shorty barrel to achieve that. That's my aim anyway).

[303Guy]

So I decided to try a thick wad protruding into the case.

http://i388.photobucket.com/albums/oo327/303Guy/Protrudingcardwad002.jpg
After sizing.

http://i388.photobucket.com/albums/oo327/303Guy/Protrudingcardwad006.jpg

http://i388.photobucket.com/albums/oo327/303Guy/Protrudingcardwad003.jpg
The wad stayed attached.


http://i388.photobucket.com/albums/oo327/303Guy/Protrudingcardwad007.jpg
Nicely protected boolit base.

Actually, I couldn't get the patched wad section into the case without damage so I simply placed the wad (four card wads) into the neck then seated a tailless PPCB. I did use a polyester filler (I couldn't find the wool wads Jeff had sent me) to hold both powder and card wads in place.

[goofyoldfart]

303Guy: what was the weight and number of that bullet? was that one of your homemade ones or a store bought one? nice configuration by the way. God Bless to all and theirs'.


Goofy(oldfart)

[303Guy]

That's a home made boolit. I call it my XIX boolit. Weight is 205gr. Those shank striations turned out to be gas cutting from a rough bore.

[goofyoldfart]

Thanks for the info. It seems like of these old warhorses like and perform well with heavy for caliber boolits. God Bless to all.

Goofy.

[303Guy]

I needed a boolit for for my carbine for a back-up gun and found a few of these left over.

http://i388.photobucket.com/albums/oo327/303Guy/214grBSAMPIGGUN001.jpg
http://i388.photobucket.com/albums/oo327/303Guy/214grBSAM001.jpg

So I decided to try them with a H4227 load. The results are very encouraging so far.

http://i388.photobucket.com/albums/oo327/303Guy/22gr2205214IMP006-1.jpg

The load was 22gr AR2205/H4350 under that 214gr notepad paper patched boolit seated to base of neck with polyester filler. It has a massive hollow in the nose and feeds from the magazine.

It was fired into a finely ground rubber tyre stopper and stopped in about a foot (300mm). This boolit is expected to kill bush hogs before they can get me so I'm hoping the rubber catch medium is somewhat representative of real life performance.

Pressure seems mild.

http://i388.photobucket.com/albums/oo327/303Guy/22gr2205214IMP001.jpg 75% flattening.

Anyway, the point is that the tail-less patch performs just great in this combo as can be seen from the fired boolit photo. There is no base distortion and no flame erosion nor any evidence of paper slip on the boolit.

Range testing is the next step. I'll report back.

[DIRT Farmer]

303 guy are you still working with wheat bran? From you advise it was the only thing that showed promise in my #4. When I got the package bigg enough for the throat, the base was below the throat and too maney devoloped a thin waist great in women not good in castings.

[303Guy]

I've just recently switched to wheat germ. In some respects it's nicer stuff and so far hasn't shown the moth infestation problem. It's is a bit springier and a bit lighter and is oily. Only time and testing will tell which is better. At least I don't have to sieve it before use and so far no baking to kill bugs needed. It is very similar in many ways. It doesn't seem to remain compacted as much as wheat bran.

It's what caused (somehow) that patch to stay on intact.

[DIRT Farmer]

I did start to get results in that rifle when I got the .321 sizer using the Lee 324-175-1R GC and lubed. I have a place to start, Apperantly my PP was to small at some point however I did pull a few case mouths out of round with the load.

My plan till September is to chase the flint lock trade gun, there is a certin trophy I want to make a run at this year. I have came close a few times. I know the load, just need to work on operator error.

[x101airborne]

Question...... 303 Guy, what type of printing is that on your boolits? How can I do that? I would like to (eventually) try paper patching and really like the neatness of your wrap.

[303Guy]

101, I've drawn the patches on CAD and made up a printer page with a whole set of copies which I then print out. The idea of the extra lines to just to guide the wrapping and also the seating depth and while I was at it I put on the boolit information (lots of different molds and varying casting lengths with each and several 303 Brits). The are scissor cut so large volume patch making doesn't work so well. It's OK for developing boolits and loads and making a few hunting boolits. My patches are curved to suite the tapered boolits I cast.

http://i388.photobucket.com/albums/oo327/303Guy/PIGGUN011.jpg

[x101airborne]

Just when I thought you could not impress me any more........ There you go. That is too cool. Very well thought out. Very professional and tidy. I (for what it is worth) am impressed. Any chance of a copy of your printer page?

[303Guy]

Any chance of a copy of your printer page?Yes of course. And thank you for your kind words.:drinks:

Actually, if you like I can design a patch specific to your particular boolit. All I need is the diameter of the casting at the rear and again at the start of the patch and the distance from patch start to boolit base. Best for me if you can measure the diameters through a single wrap of your particular paper, otherwise the naked boolit measurements and the exact thickness of your paper.

PM me your email address to me and I'll send you a copy. What paper size do you use? (Mine are on A4 - I can change that easy enough). Some printers don't like thinner paper so much. My current one handles lined note-pad paper just fine.

I've tried to find a way of explaining my method of working out the shape and size but I just don't know how to.:-|