Conversion cylinder for 1860 Uberti Army .44

[StrawHat]

That is what I started with many years ago.  

You may now grace us with your illustrations.

Have a great day,
Mako

I quit drawing stuff in the early 80s.  Now, I make what I see in my mind.  If it is complicated, I make a wooden model first.  Usually, I just modify what I can get and I am happy.  My days of drafting and design are long gone.  It was fun though.  With a computer it would be a bit quicker but with lead and straightedge, I got time to think things through so I did not have to draw them too many times.

[Mako]

...Now, I make what I see in my mind...

Hmmmmm...

[Montana Slim]

...I was able to retrieve one of the models....




The backplate & other assemblies are a bit of a jumbled mess. I was able to recover this component from a STEP file.

Sorry, it's for one of the Remington's...shhh.

Regards,
Slim

[Hoof Hearted]

Mako

With trepidation I am replying in simple terms for a simple problem.........

The way I attempted to ream this cylinder was to grind a .458 chucking reamer to accept a pilot bushing fit to the existing chamber. Then in the milling machine ream the cylinder straight through. This works well on the .36 cylinders (with a .380 reamer) and on the New Model Army ones. But did not work on a Pietta 1860 cylinder.

Great work with the CAD stuff.....but there is no need for a throat in the chamber when using heel base bullets (it will help the hollow base somewhat).

Anything tighter than 0.458 will not allow modern brass to chamber.

I have measured a few 1871/72 Open tops and they were chambered .458 with a throat (don't remember the size).

Taper, and all the other (tricks) do not seem to make sense as the largest portion of the chamber is where the bolt stop cut is.......

HH

[Mako]

Hoof,
Thanks for the answer.  The reason I was asking is that I bought a Clymer Reamer because they had one in stock.  I was dismayed when I reamed a Pietta cylinder I had bought in the bargain bin at Cabela's. The dimensions are way too large! Check out the reamer dimensions:

http://i627.photobucket.com/albums/tt358/Mako_CAS/1860%20Conversion/ClymerReamer.jpg

I have Starline .44 Colt brass so I did some experiments with Mav Dutchman bullets to see what the mouth diameter would be if I used a Lee Factory Crimp Die.  Even though these are fully in the case they are Ø.429 which basically simulates a heeled bullet with an internal diameter of Ø.429-.430.  I'm going to have Bernie make me a custom mold with a large lube groove, an O.D. of Ø.451 and a stepped heel diameter of Ø.429.

I know you use a modified Factory Crimp die for your heel based .44 Colt loads, but that is a modified .44-40 "Rifle" die with the collet crimping.  The Lee "Pistol" Factory Crimp Dies are different and have a sizing ring in them that "re-sizes" the case during the crimp.  I had already shortened a Lee .44spl/mag die to accept .44 Russian and I wasn't using it because it actually under-sized the cases which allows some blowback with BP.  Using it with the .44 Colt brass I could make the mouth Ø.451 without any problem.  I may have to have an extra sizing operation after the crimp die Bernie makes, but I have 5 stations on my Dillon.  I can make my .44-40 "Rifle" die work on the 650 and from what you've shown me Bernie's should work the same way.  

This is the chamber design I came up with below:

http://i627.photobucket.com/albums/tt358/Mako_CAS/1860%20Conversion/44ColtChamberjpg.jpg

If you look at the sections I had shown earlier, there weren't any throats and they are just like the dimensioned section above.  The area shown in green is the tapered section and the section in yellow is the original chamber bore.  When I saw you post the diameter of Ø.458 I was trying to remember if I had posted that dimension, because we seem to have come to the same conclusion on diameter.  I have a question though because I can't tell from your post, are you talking about base or mouth dimension?

The reamer ends up being a simple taper reamer that opens up the rear 1.225" of the chamber once it is bored through.  The taper gives me a Ø.452 diameter .01" beyond the maximum length of the case which should accept any cartridge I load myself.  The SAAMI dimension for a .44 Colt is Ø.456 at the base, so .Ø.458 should accept fresh brass and any of my reloads.

Regards,
Mako

[Hoof Hearted]

Mako

I actually shoot two different bullets that Bernie makes mould for (well maybe three.....). IMHO you might be trying to apply smokeless logic to Black Powder loading. No offense but I feel that you are over working things by using a .451 bullet diameter in your heel base ideologies! Do you know for certain that your bore diameter is less than .451? I see these things running about .454 on average.

Here's what I do and it works superbly:

Cast bullets from alloy just slightly harder than pure lead. I'm not sure what size they drop from Bernie's moulds but they are fine and probably .458+

Resize cases in 44 mag dies. I use RCBS Carbide ones.
Prime cases
Charge with your choice of propellent (dare I say that I also use Trail Boss ?)
Seat Bullet with thumb (the same one I give you in an upward fashion for all you slendid work)

Insert loaded round upside down in modified lube sizer die and pull handle.
Then Go shoot.
You would be surpised how accurate and "lead" free this works out to be!

Of course a generous forcing cone is in order and a liberal application of Shiner Bock!

You know I put a .386 diameter soft bullet down the bore of .36 caliber Navy's also..............

[Mako]

Hoof,
Do you honestly think I don't know the diameters of my chambers?  And seriously now...Smokeless logic?  Why don't you just say I sashay around in frilly frocks?  It wouldn't be any more insulting...

~Mako

If you have oversized Ø.454 chambers on your '60s you must be shooting Piettas.  

[Hoof Hearted]

Did I say Chambers at .454? Cause I meant to say bore size (meaning barrel).......
Might be the Shiner Bock buildup

With that in mind where I was going is why shoot .451 slugs and why have Bernie reinvent the mould?
I'm just trying to figure out the reason (and I'm sure you have a goodun).

Hoof,
Do you honestly think I don't know the diameters of my chambers?  And seriously now...Smokeless logic?  Why don't you just say I sashay around in frilly frocks?  It wouldn't be any more insulting...

~Mako

If you have oversized Ø.454 chambers on your '60s you must be shooting Piettas.  

I am busy photoshopping yer avatar.....RIGHT NOW
You like pink or ivory colored frillies?

[Mako]

Did I say Chambers at .454? Cause I meant to say bore size (meaning barrel).......
Might be the Shiner Bock buildup

With that in mind where I was going is why shoot .451 slugs and why have Bernie reinvent the mould?
I'm just trying to figure out the reason (and I'm sure you have a goodun).

I am busy photoshopping yer avatar.....RIGHT NOW
You like pink or ivory colored frillies?

Hoof,
You actually did say "bore" but I have been talking chamber and reamer size.  It can apply to either, I am concentrating on the cylinders.

There is method to my madness.  All of my Uberti 1860s (6 of them) have chambers from Ø.4505 to Ø.4515 and they work now.   Even if they were Ø.454 they might still have to bump up to "fit most bores."

Of course I have measured mine, I also ran a poll about a year ago which pretty much agrees with my results.   My bore diameters run from Ø.4520 to Ø.4570.  I have measured one pair with bore casts at the muzzle and breech ends  using cerrosafe, those are the ones I used for my models.  I verified those measurements and measured the other barrels using inside micrometers with anvil pins that fit in the grooves.  The slow twist makes this easier. The land diameter is tighter and runs Ø.4400-Ø.4420.  The land diameter is easy to measure with pin gages.

I am perfectly happy with the performance I get now with either ball or bullets with my C&B pistol barrels.  Those balls and bullets get cut and swaged into a Ø.451 chamber.  If I ran a Ø.454 or larger bullet I would have to open my chamber bores.   Which I could do but is it necessary?   Follow my logic for a minute.

Most people using the R&D cylinders are probably using Ø.452 bullets in .45 cases.  If you pull a loaded Ø.452 with a kinetic bullet puller and measure it I would be willing to bet you nuggets to biscuits they will measure less than Ø.452 when pulled.  When a soft lead (less than 9BHN) bullet hits the rifling it doesn't just engrave the bullet, it pushes the lead around (obturates) and the bore is filled.  Slug a barrel by driving  a bullet or ball through  and you will see it.  Measure it across the high points and it will measure the bore diameter.

They bump out like this:

http://i627.photobucket.com/albums/tt358/Mako_CAS/Cartridges/0003.jpg

So, now the rest of the story... Why Ø.451?  Because I want the taper.  And so did the original designer.  He may have done so to keep the chamber diameter the same as it had always been.  My 148 year old 1860 has chambers that measure Ø.4505 to Ø.4515, wow it seems that Uberti got that dimension right.

Taper will aid in chambering, extraction and head spacing , and if done correctly will allow good chamber sealing with minimal resizing of the base necessary afterwards.   Most of us know that "straight wall" chambers are actually tapered.   If I have a chamber with a mouth of Ø.458 I want my case base to be Ø.456 which is actually very tight, but I am limited by the amount of metal I have and because the commercially available shells.  But I can reliably run a tighter fit with a bit of taper and on my cartridge as well.  Turns out this is the original specified base diameter. Once again wow, who knew?

How much taper on the shell?  A case neck of Ø.454 or larger isn't much of a taper.  The Original designers agreed, they made their cartridge with a Ø.450 neck.  I'm actually pushing the diameter up since they are my pistols and I control the ammunition.

Remember the dimensioned sketch from yesterday? The Ø.452 diameter on the chamber is actually is  .010" ahead of the end of the chamber.  The diameter doesn't hit Ø.451 for another  .185" in front of the case mouth.  This is almost to the ogive of the bullet, I just get a close fit in the driving band area in front of the lube groove.

I'm making my theoretical case neck Ø.452 and and as I said before if necessary I have a station on my reloading press I can add that Lee loaded sizing die and dial it in.  So I think I want a Ø.452 cast bullet and I will take it to Ø.451 at loading.  As you pointed out there is still a lubricating step after loading.  You have experience with that, does it do anything to the diameter?  I can squeeze the diameter down if it is too tight at Ø.451 and if it is too much trouble I always have chucking reamers in .0005" increments in those ranges.

So why would I want  Bernie to "reinvent" the mold?  Here's why:

Bernie's current design (I'm sure you'll recognize this)

http://i25.photobucket.com/albums/c91/buckoff123/100_1148.jpg

What I want is similar to your modified "Remington" bullet and I also want it in 225gr to be the same as the military loads.  I also want a flat meplat.  However I am a lube hound now and I want a lot.  So I need a bullet in the diameter I want , so I might as well get the lube I want:

http://i627.photobucket.com/albums/tt358/Mako_CAS/1860%20Conversion/Bullet2.jpg

http://i627.photobucket.com/albums/tt358/Mako_CAS/1860%20Conversion/44Coltjpg.jpg



If I am going to be accused of having the logic of a smokiless shooter, then I want Pink...if I am going to swish around it might as well be girly...

Are you shooting Piettas?

Regards,
Mako

[Hoof Hearted]

Yes Piettas I have like 20 of them in some form of Conversion or another.......

Pink would not be my first choice

I understand the Lot O Lube theory but have not experienced any problems with those designs from Bernie and feel that the reduced shank might mess with your "obturation". At the least I have concerns about the lack of bearing surface in your bullet design. This is why experimenting is so much fun! Maybe your thoughts will pan out.........

Have you measured the throat diameter on any original conversions? That would tell you, without doubt, what size the bullet could have been in any given loading.

I had Bernie make me a bullet mould with a big flat meplat and I think it might even be the weight you want. But it will cast as large as the outer case diameter. I could send you some, if you want.

[Mako]

I was pretty sure you shot Piettas based on your hesitancy in trusting dimensional consistency.  I currently only own three Piettas  and unless they improve the quality or drop the price I will continue to buy Ubertis.  It appears I actually have more Ubertis than you have Piettas.

Over the last couple of years I have had the opportunity to compare 6 Uberti cap pistols of one model and 6 additional Navy pistols (3 model types) that basically share the same frame platform.  The only real difference is the one additional clearance cut on the frame, I have measured and documented the working features and overall dimensions of the pistols.   What I have found is dimensional and feature shape consistency on the individual pistols with ages that span over a decade.  To date I have only found two features that are superior on Piettas, the arbor length to barrel lug fit and the price.

I bought a pair of 5 1/2" Pietta 1860s last year because I had a $75 in gift cards and a 20% off coupon to Cabelas.  They were selling them for $199 so I basically paid $135 out of pocket for each after tax.  I got what I paid for... I'm not impressed, they are rough externally and internally and the parts are inconsistent.  Early 19th century interchangeability come to mind. I have a '58 that is a better, I picked it up cheaply as well. Once they have been set-up they should work about as well as a Uberti, so it comes down to a matter of how much work you want to put into them.

The "Lot-O" lube is not just a theory, it works.  I depend upon it every practice session and every match.  Bernie obviously hasn't shot much "Big Lube" style bullets all of his designs hearken back to very old designs.  The big difference today is that we shoot much more in a match than they did in the 19th century in a period of a few hours.  As far as obturation goes a necked down design such as I have shown will deform much more easily than either of the three you have shown in your pictures.  It's simple physics the rear section of the bullet has a short section at the contact diameter and it is totally unsupported many times the depth of the old school designs but stabilized with a central post.  It's a basic Big Lube style design and there are thousands of satisfied users.

Concerning bearing surfaces goes I think you are forgetting the depth of the rebated section is going to be about Ø.429 after crimping. I already know the land diameter is Ø.440 and if you refer to the photo I showed of the balls earlier it is easy to see the material deforms to fill in any voids.  The lead can easily fill the .0055" difference in diameter.  If you take one of your bullets and drive it down the bore of your pistol with a rod you will find it is marked on the reduced diameter section that from the beginning dimensions look like they  will never touch.  If Bernie thought it through and did some experiments by driving his bullets through bores he would have to reconsider his thoughts.  It only takes contact to provide a bearing surface.

I have measured the diameter of a Type 1  chamber.  I could only use what I had brought with me and I wasn't allowed to disassemble it.  I measured the mouth through the loading port and it accepted a Ø.4605 gage pin for about .020" to .030".  I was able to measure the chamber at the cylinder face and they ran between Ø.4510 and .4525  I made the mistake of not bringing any pins between Ø.0425 and Ø.0456, there might have been one chamber that ran larger.  My mistake in forgetting the intermediate pins also made it harder to determine the true taper of the chamber walls.
Regards,
Mako

[Hoof Hearted]

Well Good on ya!

Keep us informed as to how it all works out, my offer still stands.

My apologies to the OP for the continued HIJACK

HH

[learnfast]

Mako

[/quote]hello mako sorry to jump in on your conversation but i would like to say great job on the 3d model of the cylinders i found this site by google i am just finishing a 2d scale drawing of a colt 1860 .44 new model army percussion revolver and when i finish the 2d i would like to attemt a 3d version of a complete gun any advise or tip would be of great help looking forward to your reply

[Mako]

learnfast,
Not a problem.  I'd be glad to help.

What CAD package are you using?

~Mako

[learnfast]

learnfast,
Not a problem.  I'd be glad to help.

What CAD package are you using?

~Mako

hello and thanks for your reply i am using autocad architecture 2011