Throw out the rule book, again!

[geargnasher]

For all those who might think I'm just being a smart aleck when I say "shoot them and see" when asking about particulars with PP, here's an excellent example of why it's all speculation and educated (or wild) guesses until the trigger is pulled. When I first started trying PP boolits, I had a lot of questions and got some very good, and mostly valid answers, but the more I shoot the more questions I have that can only be answered by Mr. Rifle and Professor Target.

I've said more than once that I never had good luck with "slicks" in small caliber, high-velocity, smokeless powder applications (and I haven't), but today I did.

Another member, who may or may not wish to remain nameless :grin: was kind enough to loan me a special hollow-base .30 caliber spire point he made from scratch to try out, so I cast some up a little more than a week ago and patched them last night with my usual two wraps of 100% cotton vellum paper, sized them .311" in a warm sizer with a little lube pressure to saturate the patch with Felix lube (my standard MO with most of my PP endeavors, the patches get sized, lubed, and the patch bases crimped in one operation).

After a couple of step-up foulers to check pressures, I shot five in the .30-'06 with 55 grains of RX22 behind them and NO FILLER. The group was 3/8" at 50 yards and 2724 fps average with an SD of 11.

http://castboolits.gunloads.com/imagehosting/thum_89094f36dc69b1d42.jpg (http://castboolits.gunloads.com/vbimghost.php?do=displayimg&imgid=3910)

Pretty neat boolits, eh?

I'm going to load a bunch more and see if this was a fluke or not. Spire point, smooth-sided, 13 bhn alloy at over 2700 fps, all things that usually don't work.

These boolits have a slight taper and fit my gun's throat PERFECTLY. I think that has a lot to do with it, and I won't say the noses didn't set back some judging by the depth of the slits on the confetti. I know you can't tell much from a single, five-shot group at short range, but this gun has never fired a group this small with ANY load or boolit at 50 yards, so I'm pumped to try some more!

Gear

[6.5 mike]

Looks like the fit the throat thingy is working very well for you. What caliber & rifle ?

[Nobade]

Hmmm...hollow base boolit didn't need filler. Expanded and sealed the throat all on its own perhaps. And it looks like that nose is about perfect - reasonably slippery through the air but not so long to slump when launched.

[Longwood]

Gear;
You are not being a "Smart Aleck" at all.
You are educating people. Or I should say, teaching us to educate ourselves.
Thanks for doing the test and sharing that.

I don't think it was a fluke.
It is really hard to "Miss" in the same spot five times running.
I bet a little grin kept getting bigger as those rounds made that group.

As soon as my Clavicle heals I am going to test some paper patched 30 Caliber bullets.
I made some 45-70 bullet molds with no base cup, but I plan on machining the bases on some using a collet and round endmill. I see now that I will be doing the same with some 30 caliber bullets also.

[303Guy]

That's great! It's great too because it means the 'tapered to fit the throat snugly' principle has merit. But the hollow base may be the key or perhaps its a combination. Perhaps it's an ideal shaped throat for paper pat as well as cast.

I've long wondered about a hollow base and how it might behave under fairly high pressure (what I would call moderate).

It's rather difficult to capture a boolit with that kind of muzzle velocity but it would be interesting to see what it looks like after firing.

Anyway, I'm eager to hear how those do at longer ranges.


What caliber & rifle ?30-06. I've been hearing about the accuracy achieved with the 30-06 and cast for years. It has a wonderful long neck and although the case seems big for cast, the evidence seems to suggest it's about perfect.

[geargnasher]

I don't have any idea whether the HB had any effect on the early success of this load or not, but I figure it didn't hurt. I've never had issues with obturation using the guidelines everyone gave me regarding final sizing (a bit over groove diameter, patch to fit the throat), but the combination of the HB, taper to fit the throat like a glove, and slick sides sure does show promise.

303Guy, I wish I could recover these and look at the bases to see how they did with large-kernel stick powder, no base wad (other than the patch knot tucked into the base cup), and no filler. As far as the .30-'06 being a near-perfect CB cartridge, my take on it is it's a good one for sure, but not "perfect" for 1-in-10" twist 30 caliber unless you paper-patch, in which case you can really zing some heavy, hunting-grade lead downrange accurately. The way I see it, it isn't ideal if the best you can get with medium-weight GG boolits is 5-600 fps less than it's powder capacity potential. I maintain that the .30-30 Winchester is the best common .30 caliber for regular GG boolits in a ten-twist gun because of it's match of case capacity, accurate velocity potential, common twist rates, and that wonderful long neck. Likewise, I see no point in paper-patching for the .30-30 when you can max out the cartridge within the reasonable means of wheel-weight alloy. From what everyone is saying about it, a 1-in-14" twist 35 Whelen is probably the best thing going for the '06-sized case with GG, PP, or those (shudder!) J-word thingies, since the case capacity, payload, and accurate velocity window tend to match well with all those projectiles.

After reading through the ever-growing mould thread on the BP forum, Buckshot has just about convinced me that I can no longer live without at least a hobby-grade lathe! I could do a lot more experimenting if I had one of those and bought a stockpile of Lee two-cavity .285 moulds and ground a few cutters to make different .30 caliber cavities.

Gear

[x101airborne]

Well, heck yeah you are a smart alek!!!:kidding:

you need to bring those with you in March. If you have the mold, I would like to try out a handful and have you give me a lesson in paper patching. Sounds like just the thing for my 06 adventures. Good Job!!!!

[Nrut]

Gear,
Are those bullets casted or swaged?
Do you know the alloy and hardness?
How thick is your 100% cotton Velum?
Thanks!

[geargnasher]

Nrut, most of that is in the first post. except the exact alloy is a wheel weight alloy of unknown composition with about 1.5% tin added and it fully ages to about 14-15 bhn air cooled, these weren't quite there yet. They are cast, not swaged. It's a really neat nose-pour three-cavity mould with a HB block that has plugs in it. I think I forgot to put the core diameter, it's .3045" and parallel on the part that goes in the case, tapering to .301" at the break in the ogive. The paper adds a shade over ten thousandths to the boolit when dried, I think it's about .0028" measured dry with a mic.

Gear

[Nrut]

Thanks Gear,
I read your OP at least three times and don't know how I missed the BHN info below the picture..:shock::veryconfu
The reason I asked about your Velum thickness is that mine is .003' thick and only shines in my 9.3X74R..
Not so much in my .35's or 8X57..
regards..

[Haggway]

That looks like science graph paper. What brand is it?

[CJR]

but this gun has never fired a group this small with ANY load or boolit at 50 yards

This statement about PPCB accuracy is exactly what I have found. It is the very reason why all the "blood,sweat, and tears" is worthwhile. Any time you can surpass jacketed match bullet accuracy/velocity with inexpensive PPCB, it's a great day!

Congrats on your effort! Hope springs eternal!

Best regards,

CJR

[nanuk]

[QUOTE=geargnasher;1586983.... It's a really neat nose-pour three-cavity mould with a HB block that has plugs in it. I think I forgot to put the core diameter, it's .3045" and parallel on the part that goes in the case, tapering to .301" at the break in the ogive.
Gear[/QUOTE]



I guess GoodSteel's mould that he showed pics of on another thread.

do I win a prize?

[geargnasher]

Your pink "Hello Kitty" beanie and puffy sticker set is on it's way to you, Nanuk!

Gear

[geargnasher]

That looks like science graph paper. What brand is it?

I forgot! It's the same brand as all the graph and grid papers are in the drafting isle of Office Max. They're proud of it, too, it's like $15 for 60 sheets. If you really want to know, I can go down to the gun room and dig out the pad.

Gear