Nose-Patched 2-Diam. PPCBoos

[Zeek]

The idea of just flat patching it all, on a 2-diameter rifle-type CBoo (so that no lead is exposed), is very interesting idea. Sometimes, you can get only part-way there (see below), but it is still worth the try. I have all of the following ready to try tomorrow at the range.

Here is an L311041: no GC; 13 Bh WW alloy; 2x16# full-length patch; Rooster Jacket & wax lubes; for an H&R Topper 30-30 with a 0.5"-long 0.310"-cylinder-then-3degr-inclangle-leade-cone throating. So, the LOA on this baby is 2.7". At that LOA, the patched-nose is sitting against the leade cone and the patched front bands will be in a slip-fit into the long throat cylinder. When the round goes off, the nose should engrave (crush the patch then push some land-marks down into the nose cylinder).



This is the NEI 322-165 DD (cherry #90), which comes with a built-in "DD-band" (self-engraving nose-ring ~~~> gives a short section of bore-riding nose regardless of the barrel's bore diameter, within reason):

I just made up a batch and have yet to try one. Alloy is annealed WW (~13 Bh). I put a GC on for the heck of it, and pushed them thru a Lee (custom) 0.318" diameter push-thru die, using Lee Sizing Lube (electrician's wire-pull water/wax emulsion) to avoid leading the die. The cylindrical nose cases at 0.315. The 2x16# patch added 0.010" (bands/nose = 0.328/0.325), so the final push-thru Lee 0.325" sizer yielded a uniform 0.325" diameter exterior, but the nose part of the patch is not compressed. I had to forego patching the entire nose, due to LOA considerations ~~~> even this move-back of the PPatch front edge gives an LOA of only 2.8". NEI will be coming out with lots of neat DD-banded CBoos in the near future. This one has a K-BOWM point [see http://www.neihandtools.com/ & click on bullet picture at the bottom of the screen].

This is the RCBS 30-150, a plain-based design. It has a 2X20# patch sized to 0.310" for my H&R Handi-Rifle. Initial size-down (soft WW-alloy) was to 0.303 (custom Lee push-thru die).

The rifle's modern-type throating (short 0.310" diameter cylinder then the leade cone) gave LOA problems again, unless is moved the PPatch front back to expose part of the nose. However, because this CBoo has a 0.299" nose diameter, it won't touch the barrel's 0.304" diameter bore, so the short bit of PPatch extending forward of the drive bands will be needed to support the bare part ~~~> another way that a PPatch on the nose can solve a nose-ride problem. I HAD planned to patch it full-length, but the modern-type throating just would not allow it. The experimental throating described above (for the Topper) was, in part, to investigate a potential cure for this sort of problem. The only thing is that such a rifle then becomes rather a dedicated PPCBoo thing.

[longbow]

Looks very interesting ZEEK. I will be looking forward to your results.

I am particularly interested in the RCBS 30-150 "half jacket" paper patching. I have been wanting to try something like that myself but haven't gotten to it yet. If your results are good I will have to get off my butt!

Keep us posted please and thanks.

Longbow

[303Guy]

I'll be looking forward to your results too!

I like that real neat fold/crimp with a perfect circle hole.

I can't make out whether your patch ends just meet or have a slight overlap (or gap). They look good either way.

It sounds like your rifle is the perfect set up for PPCBoo's.

[barrabruce]

Please Keep us posted.
I to have a H&R 30-30.


I'm hoping that will work with a light coating of alox on the nose.
A full case of slow powder for no lead issues.


Just started to experiment along the same lines as well

Nice wraps too.

Bruce

[Zeek]

. . . I like that real neat fold/crimp with a perfect circle hole.

I can't make out whether your patch ends just meet or have a slight overlap (or gap). They look good either way.

I picked, for that image, the PPCBoo with the preeeetiest fold/crimp.

I calculate my patchlengths using a special deformula, then just cut and patch. Normally, they come out right on the money. I use a 30-degree angle (off of the straight-across cut), and compensate for that angle-cut's longer-than-straight-across length by multiplying the calculated paper-strip width (= 2 x pi x band-diam) by Cos 30 (i.e., multiply by 0.8660). It comes out perfect every time, usually.

The first try on the RCBS 30-150 PB (made into a PPCBoo for the 7.62x39 30-cal H&R Handi-Rifle barrel) did just okay on my first try, so I'll have to get back at it, probably after the June Shootists' Holiday, which I must now get ready for big time.
Regards, Zeek

[barrabruce]

Good to hear they showed promise.

[Zeek]

I had to cut off experimentation with my SMLE, as something in the bolt went haywire (clicked but failed to fire & would NOT re-open). Had to use a soft mallet to get it open (to avoid carrying it home charged!) & that did some bolt damage, so I'll be replacing it.

Therefore, am switching to other rifles, including my K98 8mm-Mauser. Like the SMLE, this chambering has long (very-shallow-angle) leade cone. I patched this standard 13 Bh (WW+Sn alloy, air cooled) 8mm CBoo full length with a 2X16# jacket, but then found that the leade-jammed LOA was only 2.8", so I cut off some of the front of the patch to expose some of the nose, which brought the LOA up to a more manageable 2.9+".

Well, it is still a band-and-nose-patched PPCBoo. As you can see, the standing bullet got wrapped just a bit more than 2X around, but most ended up right on the money, as shown on the recumbant PPCBoo. We'll have to see how it works on-target.

While making this one, and whimpering over the need to expose some of its nose, my NEI 318-170 mould came in. Casting some up with it showed a CBoo with 0.322" bands and a 0.310" diameter nose cylinder ~~~> the bands are a bit small (in diameter) for use, as-is, in my K98 & the nose is barely big enough and only at the muzzle. So, on this one, I decided to use a full-length 1X label patch, as shown here.

The left is the as-cast, then the full-length 1x adhesive label patch, then the finished PPCBoo, with its shortened patch (my M-Nagant would not let the full-length-patched PPCBoo sit out far enough for practical use). I cut off the too-line nose patch after the PPCBoos had been sitting in a 200F oven for over an hour, and I can really guarantee you that that puppy is glued on there big-time. You'd think that I would learn to set up a test boolit first, then make the patch length to suit the outcome of that test.

Note that the finished bullet shows the overlap of the adhesive label over its starting location. The final process was to run the boolit through a 0.325" Lee push-thru die to size down the patch (0.327+" diameter) and to crimp on the check. Why the check? I don't know if this sort of PPatch will work, given that it is VERY thin (0.0025"), so I thought it best to add the GC.
Zeek

[303Guy]

Might I ask what exactly happened to the SMLE? Do you have pics of the damage?

[Zeek]

I don't know yet, but soon will. I have ordered the special tool needed for taking the bolt apart.
Zeek

[barrabruce]

Special tool.

Ohh you don't grip the firing pin then with pliers and unscrew it from the back bit then???

My half patches turned out dud's.
But I will try some more soon.

Barra

[Zeek]

Paladud: Half-patch, won't travel.

[6.5 mike]

Zeek, I have been following this while I was on the boat. I'm doing somewhat the same thing for a undersized lee mould that is small on the nose. The mould drops at 0.2975/0.3095, hiwall barrel is 0.301/ 0.307. this brings the nose up to 0.301, then sized to 0.309 for a 30-40 krag uberti. Two wraps of meade tracing paper is what i'm using.
So far I'm getting good grouping at 100 yards, but still have along ways to go until I get where I want to be with it (mostly the fool behind the buttplate). lol.

[Zeek]

That's good news, 6.5 Mike! I'll be trying some more tracing paper full-length approaches soon.

The complete bolt assembly for the No. 1 Mk. III arrived from Gun Parts, together with the neat little bolt dis-assembly tool, which let me get my troubled bolt apart. I ended up needing a bit of ballpeen hammer work on the bolt body, but needed to replace the cocking piece (used the one on the new bolt), as it was seriously damaged by the soft-face mallet work needed to get that damn live round OUT of that rifle so I could take it home. I still have no idea what caused the mis-fire/tie-up at the range, but I'll give the rifle another try this Sunday. The good news is that I don't need to replace the bolt body, for that would have caused headspacing issues.

This time around, I'll be trying higher pressures (~45 Kpsi, rather than the previous ~35 Kpsi loads), and will use H-4350 and IMR-4350 (rather than AA-2495) so that I have only case-full or compressed-charge loads. I hope that causes some success. This series has resulted in well over 100 targets, so far, with most PPCBoo loads running over 2.5" at 50 yards = not worth trying at any greater distance.

I have found that getting good accuracy with PPCBoos to be far more challenging than when using j-word pills. The only PPCBoo successes have been with the 38-55 using ~120% charge density (use the swirl charge technique to get a denser-than-normal pack, prior to compaction), AA-2595 powder, and ~45 Kpsi max pressure. This works great for the 38-55, so will try that pressure range with my other rifles and use a powder that will give that pressure with a casefull load. I sure hope that does the trick.
Zeek

[Zeek]

Well, I got to the range today with the fixed-up SMLE, my K98, and my H&R Handi in 7.62x39. The general changes, since the prior very unsuccessful work the prior Sunday, was that I included higher pressures (up to ~45 Kpsi) and used powders that would fill the case at that pressure, and would nearly fill it at lower pressures.

Conditions where terrible, but could have been worse. I had a 20-to-30 mph wind all day, but it was coming either head-on or from no more than 20 degrees off to my right. It blew over the chronograph several times, twice with five sand bags attached, and reached into a hidden cranny, sucked out my powder pan (used to transfer to my scale pan from the dispenser) and blew it either to the ground or (twice) against the chain-link fence and held it there, preventing it from falling to the ground.

So, I was especially glad to be shooting at 50 yards, where the wind effect would not control the results. At this point, I am looking for loads that need to be winnowed at greater distance, but 50 yards serves VERY well to identify the bad loads (2+" groups) from the more promising ones. If I get to the point where I have a bunch of loads going into a nickle-to-quarter diameter at 50 yards, I'll know that it is time to move the target out. That time is not now.

The "half-jacket" RCBS 30-150 PPCBoo pictured above, at best, gave 2" groups with a variety of AA-2520 full-to-fullish charges. The throating is "short," making it necessary to leave the 0.298" diameter nose and point exposed, and that nose/point is totally unsupported across the barrel's odd 0.304 bore (yes, and that with a 0.3097" groove diameter), so that may be the cause of the poor performance?

I tried several traditional and experimental PPCBoo designs/approaches in the SMLE, all to rather poor effect, regardless of pressure.

The K98 really hated an L311299 with a 2X tracing paper jacket-won't-hack-it; again, this was regardless of pressure, using full-to-fullish H-4350 charges. However, with AA-4350, The SAECO 8-190GC (sized 0.319 w/GC, then 2X16# patch sized 0.325, at 2.95" LOA = jam-into-leade) gave groups as small a 1.15" at ~2000 fps, which is a lovely break from the 2"-to-4" 50-yard groups from most of the other 160+ targets shot so far in this PPCBoo investigation.

Overall, my experience is that getting any real accuracy at all with PPCBoos is far more daunting than getting similar accuracy with J-words, and the span of good-performing charges (lightest to heaviest) is rather narrow and success comes mainly with powders that fill, or nearly fill, the case at whatever turns out to be within the sweet-spot pressure range. Once more, this is FAR more touchy than with J-word workups, whereby one can get to the point very quickly, with 70% to 100% casefull loads, where it one MUST go to 100 yards or farther to complete the winnowing-out process for that particular rifle. I know that many of you have reported an easier time of it, but that is my experience.

At least the PPCBoos are beginning to perform, but I am in no way feeling the need to go to 100 yards or beyond. Although today's conditions were worse than usual at this range, I still got a few loads that show promise.
Zeek

[303Guy]

Mmmm..... I've shot into almost head-on, unstable and strong winds with terribly disappointing results. I suspect a strong head-wind can ruin a shooting session! (I've experienced tail-winds actually lifting a bullet at long range! (Well, reducing the drop dramatically!) Wind can even cause a fellow to squeeze the gun too much and spoil groups that way.

[Zeek]

I agree all the way, 303Guy, but I did get some way-better-than-abusual groups. This range usually has wind issues only in the afternoon, and I fire all day long, when working on an experiment. That is why I choose my initial-cut work to be at 50 yards ~~~> the bad-load effect is vast compared to the wind effect, and it is far enough away for a bad load to really "show its stuff" (larger groups). So far, this has been a valuable approach, given that it allows me to continue working throughout the day. Last Sunday, though, was a humming-dinger riot from the first . . . . just blowing like mad all day.
Zeek

[303Guy]

I've been playing around with bore-ride PPCBoos right from the start and being me, I made my challenge just that much more challenging by wanting a decent heavy boolit! Depending on which gun is the flavour of the day, I may need to size the boolit or not. For the sizing, I make the bore-ride section smaller than bore and wrap to over-bore diameter. Such a sized and patched boolit sizes the patch under the rifling on chambering but leaves no impression in the core. On firing, the nose section shows nice rifling impressions. (I'm using printer paper at the moment as it's thicker and more compressible than note pad paper). With enough powder charge the patch disintergates just fine. With too little powder the patch loses only the outer wrap and with even less (sqib loads) the patch comes out whole - almost. Problem is, I have not had a chance to range test these sized, two-diameter, PPCBoos. I have tried cig paper using a single wrap on the nose and and two wraps on the rear to get them to fit the throat. I may have loaded these too hot as the accuracy seemed promising at 45yds but was terrible at 190yds although there was no boolit yaw. (I used a very large cardboard as a target).

[Zeek]

Well, the "half-jacket" approach for the RCBS 30-150CM worked poorly. However its undersized (0.298) nose tempted me to try something new. The H&R Handi-Rifle 7.62x39 barrel has a 0.304" bore diameter (by 0.3095" groove diameter), so I thought I would try taking advantage of the vastly-underdiameter nose by configuring a patch (for both bands and nose) that would give the ideal fit in both places. That turned out to be a 3Xtr.-paper patch, put on after sizing the band diameter to 0.307". After the patch dried, I sized the bands in a 0.309" sizer. The PPCBoo moves into the modern-type throating (short 0.310-diameter cylinder behing the three-degree inclangle leade cone) with ease, and will need to obturate only a half-thousandth to fill the grooves.

This left the nose untouched at 0.305. The PPCBoo at the right in this image has been pushed into the throating (gives an LOA of 2.15, which is "just right") and you can see the mark of one of the lands on the nose and also, somewhat, on the front drive band.

I figured that this idea is worth a try, given that this bullet's point design is "about perfect" for hunting (a K-BOWM type that will give a MAJOR whump on impact, will penetrate deeply w/o tumbling, and will leave an effective long permanent wound channel). I hope to give it a try on paper targets this weekend.

Here's one thing to consider. We vary our paper weight and number of wraps all over the place, but I think, sometimes, we run into trouble because our PPatch is not as thick as the difference between the bore and groove diameters of our barrel. Of course, the patch's REAL thickness (after it gets crushed from bullet obturation) will be only ~60% of its as-wrapped thickness. Just for reference, this patch adds 0.006" to the core CBoo's diameter (before sizing the patch), and the barrel's groove diameter minus its bore diameter are also around six thousandths (the barrel's rifling is not as "tall" as standard). So, let's hope this works, as it may explain why tracing paper patches (standard 2X wrap with much "taller" rifling) often works poorly.

Along that line, think of the 8mm Mauser rifling, which can be 0.326" groove and 0.311" bore (a difference fifteen thousandths!!). Thus, a 2X16# three-ring-notebook-paper patch (adds only 0.010", before sizing) is only two thirds as much as the groove-to-bore differential. We really need to work on how thin the as-patched additional thickness needs to be for a given groove-to-bore diameter difference. "Better thinker than stinker!", I always say.
Zeek

[303Guy]

Looking good! That's exactly what I get (and haven't range tested yet). What I have tested is a different rifle with a more worn bore at the chamber end. That one accepts the boolit in the unsized condition, i.e. with only its as cast taper. The muzzle end is almost on spec. These shot quite good for crappy 'v' sights. Took a turkey!

[Zeek]

Having had to trim off the front part of the nose-patch for several PPCBoos (in order to prevent a too-deep seating depth), finally, I figured one way to get a full-length patch, at least for my K98 in 8mm Mauser. I sized the two-diameter CBoo down to 0.319 on the bands, then gave it a 3X patch using tracing paper. This adds 0.006" total, so the bands measure 0.325" and the nose 0.321" (as-cast nose diameter on this CBoo is 0.314).

The PPCBoo shown above has been pushed up into the long shallow leade cone of my K98, and shows rifling marks both near the front end of the patch and on some locations on the front drive band. In spite of featuring a full-length patch, the pushed-into-the-leade-cone LOA is 3.05" (just right).

I was not able to test the PPCBoo today that I described in my prior note. If it does not rain tomorrow, I'll try it (in the H&R 7.62x39) and try the one shown above in my K98. This one (in the K98) will be my first PPCBoo that is not sized-down to final diameter ~~~> this one wraps to final diameter (0.325"), leaving the PPatch unchrushed, so the CBoo core will have to obturate around 0.002" in order to crush the patch, thereby creating a hard paper jacket. I hope it works, as it sure is simple to size just once (to 0.319) and then patch up to final diameter.

Trick 1: 303Guy, this one's for you. In order to avoid getting a "loose nose / tight band" PPatch, when using a parallelogram patch blank on a two-diameter CBoo core, and assuming that you roll with the bullet's point to the right, tilt the CBoo around three degrees point-up. Then, when you roll (on a mouse pad), push down strongly on the nose part as you roll, so that the CBoo's rear end follows a bit of a curve. Since it is going to "climb" to the left a bit (due to this non-square start), you need to start with the CBoo's rear end just a bit further to the right than usual. The wrap looks a bit odd on the two ends, but the ends line up nicely (overlaps a bit on the nose, but is just right on the bands).

A second benefit to this approach (on a mouse pad, push-down/rolling on the CBoo's nose) is that the part of the patch that overlaps onto the CBoo's point gets all nicely folded down, as shown in the above image.

Trick 2: I observed a potential problem with twist-&-cut tails when the PPCBoo is then pushed through a Lee sizer die. That little "twist wad" in the center of the PPCBoo's base is the only part of the boolit that is pushed, with the result that the wad gets pushed up into the base of the CBoo core a bit. This dent could cause an unbalancing of the boolit's "steering end." This makes a damn good reason to use the round-the-corner-and-pleat-it approach, rather than the twisted tail approach. Even if you don't give the PPCBoo a final pass through a sizer die, the same effect is likely to occur (wad dents the CBoo core's base) when the round fires.
'Nuff said,
Zeek