New boolit needs work, need help

[Racing]

Ok.
So this is for a BP ML.
An old French take on the fabled 451 rifles, rendering a rather sleek gun carrying most of what´s needed.
1:21" twist, 45cal and so forth.

As we were in need for a few different projectiles we CNC´d three molds in one based loosely on the old Postell. Two of them being bore riders, and these work a million bux.
The one for the muzzle loader though, not so much.

As we fire the piece we get poor accuracy at 100 meters, albeit SOME sort of accuracy. Ie; one 8 and one 9 at an intl pistol target, while the 3d round can hit..hold on here, 18 FEET high!
We see clear evidence of key holing at 50 meters. SOME of them.



Boolit loosely based on the Postell. 4 drive bands, just.. ML remember. Weighs around the 500 grain mark. Boolits used weighed to within under 1% weight deviation.

Have tried with loads ranging from 55grains to 90 grains. We at first thought it got a tad better as we increased loads and omitted greased 1/8" wad but.. as it turns out, no.



Now. Obviously boolit to the left at 11,05mm diameter. What is here though is that the rifle indeed carries a 11,05 base but measures a full 11,65mm in the grooves. Ie; a depth of 3/10 of a millimeter, and where we´re at we´re talking this being the culprit.
There´s simply no way we´ll get the base of the bullet to expand that and thus the manner in which to keep some sort of seal is due a greased wad at its base.
In short i believe that we´re experiencing rather advanced amounts of flame cutting, hence the hip hap behavior as we can have a few boolits "semi" on target while all of a sudden we have one massive amounts off. To the point where we said enough due the dangers inherent.



Rifle is on par every aspect there is. It is an old French made Felix Escoffier from 1865, that carries its age with pride.



Has been bedded and all of that, sports a diopter setup. Has been handed a fresh crown aso. In short, as far as the rifle ...count that out. This is a bullet issue only.

Only thing that clogs the picture is this INSANE rifling depth and how to cope with it. It´s to the point where i´m giving thought to getting a 11,35-11,40mm reamer to run through there to get within realms.

The basic projectile in short works da bomb, we know this from the "other two" intended for the just as French Chassepot breech loader and the Brit made W-R Monkey tail, where they run like friggin tractor beams. In these the boolit shape runs very very well, and this at semi extended ranges too (inxs of 300)

As i see it the main culprit here is that one way or another we need that bullet SETUP to seal vs the rifling and the rifling being 3/10mm deep.. not happening in my book.
A sorts of Minie cavity was suggested, but again.. although the bullets are out of pure lead getting them to expand a total of 6/10mm is just out, if we want to see any shape of integrity left of the base projectile.

(Btw. For you fraction guys just divide by 25,4 to get inches).

So.
What gives?
I need ideas guys.

[Dusty Bannister]

I suspect you are using a soft black powder lube. Any thoughts to dipping the base of the bullet in hot beeswax to fill the bottom lube groove, then adding the BP lube to the remaining grooves? The grease wad is either felt or card. Felt may not provide much of a seal.

Since this is a muzzle loader, is the bullet diameter tapered or just the base band reduced to allow easy entry into the muzzle.

[charlie b]

Have you tried hard wads?

First I'd try a 1.5mm or so card wad, maybe a felt wad on top of that. Alternate. Poly wad. I've used poly wads in .357mag instead of gas checks and they work well.

I'd be tempted to try paper patch. I tend to use paper patch with slugs in my front stuffer.

The other thing is to use really soft lead, around 8bhn. Even 1:20 seems to be a bit hard to get to expand in the bore. I still have to use quite a bit of powder on some slugs to get them to expand. 80gn is minimum for my .50cal and 450gn bullets. I'd start with 100gn and see how it does.

Look in the muzzle loader section and post this in there. Someone may even have a similar rifle to compare.

[Wayne Smith]

Only one idea, and it comes from the history of cartridge loading - but - When the US Army started loading the 405 gr. boolit in the 45-70 case they found they had to establish a significant crimp to get complete powder burn. The 520gr boolit had enough inertia to accomplish this, the 405gr didn't. If you have something that either slows down the start of the boolit or eases it this may create some of what you see.

You are also unlikely to get much expansion with that boolit unless you are essentially casting it pure lead, i.e. very soft. That's why the Mine boolit was cast so soft as well.

[Good Cheer]

Do not despair. Hexagonal bored rifles work quite well with round boolits and that takes a lot of expansion.

Try a boolit with copious grease grooves over its entire length and a very hard card wad.

[Racing]

You´re correct on that one, i happen to own an original Whitworth too.

The slug you´re thinking of is another Lyman and it might very well be we´ve been off mark, the so called volunteer boolit.

Yes. Of course the slugs are out of all soft lead - no alloys what so ever.
Yes, we´ve tried various wads and over powder cards and what not. Same end results.

Thing is though, that reflection as far as the Whitworth is 100% correct. Seeing the very very deep rifling of this gun it stands to reason to NOT make the boolit fill up the grooves but more so just take to the rifling in a productive manner.
Actual seal can, as noted, be handled in several ways. A greased wad just being one of them.

As we aim to use this rifle for comps it is essential with a repeatable solution. Ie; one that we in an about anal fashion can do when we load her up over and over, as the idea here is shooting for points.

Thus the actual expansion of the boolit, as i conclude, needs to be repeatable as well and as we strive NOT to fill the grooves this becomes somewhat of a variable, for instance depending on loading doctrine as well as powder charge and what not.

[Racing]

Right.
Eventful sunday, spent measuring with a rather anal approach, calculating and debating with ppl - some with more insight than others.

Have a fair idea of "step 2" in all of this and will try and have a mold ready for testing come this week.

Anyways.
Seeing the rather profound rifling depth the whole thing will have to use a seal and this seal will be a greased 1/8" wad for starters.
Have used greased felt wads for ages and believe in them.
In my Westley Richards Monkey tail breech loaders for instance we use them to seal the chamber, rearwards, as we use the gun. Ie; a greased wad is the last thing the actual breech plunger sees, and this works very very well - albeit a somewhat thicker wad of the same diameter though.

Real culprit here is that downright insane rifling depth. For a breech loader we get away with it but for a muzzle loader this turns into an issue.
Getting the boolit to take to the rifling is one thing, we in essence just need to make that happen in a sustainable manner, while sealing the rifling while at it, expanding.. Not so much.

Asking ANY boolit to expand that much and keep integrity as well as especially base form is simply not doable. At least not in a sustainable fashion.

Of course the tech "correct" thing to do here would be to run a reamer through that barrel but that would also bring that we destroy the historical both value and importance of the gun.

The actual gun was the French take on the 451 caliber volunteer rifles of the time, the time and place where "modern accuracy" was born.
Many attest this to Sir Joseph Whitworth but having dwelled on that subject quite substantially i say that´s just partly true.
True is that Sir Whitworth was part of a trinity consisting of Islamabad Brunel and the above mentioned Westley Richards (who btw produces very very expensive guns to this day).
But.
At the to the letter same time, as often in history, the same ends were concluded by Purdey (yes..again very very expensive guns) in his "express" rifles. The ones that evolved into the african plains guns rifles.





So hen or egg? You tell me, but suffice it to say these rifles came to alter how we build rifles to this day and the Greener formula in turn.. well..

That being said, as i note above, we campaign an original Whitworth too. One of the "true" Whitworths, one of the first approx 5500 produced.
It has since long, as also noted above by Good Cher, been proven to work just as fine with cylindrical boolits, albeit the sights of the thing are set with two references/parameters.
H&C.
H for hexagonal obviously.

Anyways.. just blabbering... Trials with the new boolits asap. Will report back.

[Racing]

As it might be of interest.
Felix Escoffier was one of the heads and one of the four major arsenals in France at the time. In his case, St Etienne.
This let him produce guns to evaluate as well as for simply SnG, of which this is one.
The french had by this time certainly caught on seeing the advent of the fabled Chassepot rifle - by many considered the worlds first "modern" rifle. (It´s in short a 45cal 1:21 twist single shot bolt action)
Well.
This muzzle loader is anything but and i´m rather certain it was developed as a take on its British brethrens.

The differences though are rather profound. Trust me, i´ve handled a Brit made 451 gun or two by now..and own a few to this day.









Imagine if you will a 451 volunteer rifle where you let a pack of talented French designers loose. The remarkable thing about the gun is how low key it is, nothing reveals it. Not one yota.
No engraving, no checkering no nothing and the lock plate simply states "Felix Escoffier". But OH..trust me. The trigger is to DIE for..the actual trigger is designed in a manner that your trigger finger simply takes to it.
The stock so slender it makes a Brit 451 rifle come off as a damn log. Due result the thing is a mere 2,5kg worth.



Here friend Patric letting her rip. Patric and I is what makes the team so..

Yes. There´s others out there. It´s marked "52" like all over, and at first i thought this was the caliber per the Brits "bore". Not so. 52 is its serial.

Had issues finding a nipple/cone for it that´d fit. Looked very much like a 1/4"-28 just.. "fatter".
Indeed.
British imperial threads.. inches. Correct. Now, this is where it goes clusterXuck as there was a German inch too which is a tad larger than the British and in turn.. you guessed it, a French inch as well - which is even larger.
So.
1/4" nipples are produced oversize, good thing for me as it turned out that a 265"-28 was right on the money.

This altho the French had taken to the metric system by late 1700. Yep. Them ran BOTH systems side by side as it turns out.

[Racing]

Alright.
So update on the matter.

Having thought hard and played around with Greenhill (Miller) and what not i´ve concluded that i will shorten the boolit somewhat from the Postell approx 36mm to 32mm.
In turn the base of the boolit will still be flat base while the first driveband up from the base will be widened to a full 5mm. This followed by 3 grease grooves.

The ogive and what not stays.

In turn i´ll use it with greased felt wads only for starters, seeing the excessively deep rifling in an attempt to keep gas cut to an absolute minimum.

Will report back with CAD pic.

[Racing]

Ok.



Version 102. After battling with both Greenhill and Miller i concluded that as this is to be a "short range" boolit i shortened the envelope some to move the stabilized area downward as far as muzzle velocity. If my calculations are on the money this one´ll handle lower than 1000fps need be and hand me an "s" factor inxs of 2 at approx 1400fps.

In turn i mike´d the barrel and as it turns out it is a min of 11,10mm approx 7-8mm in from the muzzle. Seeing this we opted to make the mold 11,20mm diameter this time out.
From measuring the lead WE use (pure lead) i measured a full 7-8/100mm shrink as i drop the slugs into water. Thus an 11,20mm mold will make the boolits hold 11,12 to 11,13 most likely aaaaand....



I thus modified an old loading tool for a 375 H&H to become a calibration eye instead, handing us 11,11mm worth.

As you can notice the rear drive band of the new boolit is way more sturdy and this as i PRESUME the excessive amounts of lead in the barrel was from the minescule drive band of the "old" design to shear off under load. I both hope and presume this wider band will take a LOT more heat as far as that.

This mold we´ll cut tomorrow night and from there i´ll proceed casting the fresh boolits. As a safe guard, that i really hope we won´t need, i´ll cast 30 in which we´ll drill a "minie" hollow on the lathe.
That said no matter this time out i´ll back the boolits with an 1/8" thick greased felt wad. This to ensure a seal and thus cut any and all gas cutting to a dead halt. A greased wad as it is repeatable in comparsion with grain,polenta or whatever.

We´ll take it from there i guess

[GregLaROCHE]

That sounds like a really nice gun. Was it originally made for competition or hunting?
Why have you ruled out a hollow base?

[samari46]

Hollow point the base like they did with the 58 caliber minnie balls. With the deep rifling you mentioned you'd probably need a hammer if you tried to load anything like a full dimensioned bullet. So just create a pointed hollow point in the base. Try it out with either bullet lube in the base or without. Would work well if only pure lead were to be used. Frank

[Racing]

@ Greg.
At the time there was about a plethora of guns marketed as "military match". This Escoffier rifle i´d say follows that idea.
So yeah. It´s a match rifle alright, just with the bracketry for bayonet and what not due competition rules at the time (into the 1860´s in Europe)

@ Samari.
Yes. Noted. Traditionally though the 451 era guns used flat based boolits all of them basically, and this to great success. Where this one stands out though is the insane rifling depth, and i truly doubt that any boolit would take to that dimension change with kept integrity. Mark.. this is about absolute accuracy and with boolits out of pure lead in 45cal and the charges used.. the boolit WILL obturate. Q just is to what amount.



Mistakes. Mold got cut alright but.. the palette for the CNC we loaded up with a 2mm pin and.. no good for a 1,9mm cut. So the cut stopped short of what was intended, and we´re going to adress that of course.



Having cast a bunch tho i was hot for teacher why i reasoned as such that although that center section with the grease grooves of course matter it won´t have a profound effect on total performance.
Boolits at this rate coming all in at 420 grains.

So we, as i wanted some sort of receipt on if i was ontrack or not, went shooting. Indeed the difference in performance was no laughing matter.
Mind you, this then being a bullet for short range work.

So. First outing we ended up with a rifle that needed reset of sights. That done coarsely we right off the bat had 2 9´s and a 7 for a three shot series.
Thus we´re going to continue working with this boolit and first up hand it a load ladder. Second, seeing the taper of the rifling dimensions, hand it a sorts of indent out rear to aid expansion and see where that takes us.