Building your own conversions

[Professor Marvel]

Greetings Citizens -
I am embarking upon one of the simplest of conversions - the Remington .36 to a .38 Long Colt healed bullet. To begin this experimental endevour I took a virtually scrap .44 Pietta Remington cylinder and bored it through.  My plan is to sleeve each chamber with 7/16 tubing (ID of .375) which is a tight fit, silver solder it in place, and chamber these sleeves to .380- .381.  After boring, even though I maintained the same (or somewhat smaller) initial ID,  I found the cylinder walls to be remarkably thin at the bolt notches.

Thus I would like to ask  those who have done these conversions in .44 and .45, how do you maintain a safe wall thickness? do you start with a stock cylinder, a cylinder blank, or mill your own cylinder from stock? if so, what is a good steel to use for such a cylinder? I can readily get C1045 ...  Do you lathe the cylinder somewhat oversize? Judging from the fit of the cylinder in the fame there appears plenty of space for a cylinder of several thousandths larger diameter. I also found that an ASM Remington cylinder is about 1.637 inch in diameter while a Pietta is 1.595 inch in diameter

my thanks in advance -
yhs
Prof Marvel

[Hoof Hearted]

Marvel

You lost me a bit here.
What is the OD of the tubing (or better yet the ID that you bored the cylinder to)?

I only ask because a 36 C&B cylinder should already be approx. .375, yet you are boring a 44 to accept tubing that has a .375 ID. Not trying to be smart, but it seems you have taken the long way around, so to speak

The original factory conversions utilized the original cylinder bored though with the back either cut off ala Colt style (conversion plate with a rebounding firing pin) or a soldered on rear extension ala Remington style. This is why they used heel based bullets.

HH

[JP Anderson]

I'm mighty busy tonight and leaving for the weekend in the a.m. but will post this quick comment. The thin notches was a problem on the old Colt conversion and many antiques are broke through.

So far with my conversion project on my 1860 Army I've went ahead and machined a 5 shot cylinder (.45 cal). I rejected modifying a cylinder because the walls would be far to thin and the notches would probably be open by the time it was to .480". But .38 is a different story and so is working on the Remington.  Seems like a lot of the same problems as my project. I did leave the overall diameter of my cyl. as large as possible.

I wanted to know I have the best steel I could find and know what I had. I'm not sure what Pietta uses and that bothered me. You should be able to order a short length of quality steel online if you look a bit. Shipping and handling will probably be more than the steel.

I've considered converting to .38 and sleeve a stock cylinder as your trying. I actually wouldn't mind a .22 conversion using that method. 

(Ignore this part, I see on review you were asking about the notches when it's a .45 conversion) My initial thoughts are the sleeves should support the thin material in the notches. I would use 4130 aircraft tubing to make the sleeves. Kind of depends on if the walls on the sleeves are thick enough to handle 100% of the pressure. I don't know how to calculate the required wall thickness even after a long search for a formula. Seems ballistics isn't a hot topic in modern engineering books.

I'll be back early next week and post a few more thoughts as this thread progresses. Good questions.

Thank you,


John

Havre, Montana

[Professor Marvel]

Marvel

You lost me a bit here.
What is the OD of the tubing (or better yet the ID that you bored the cylinder to)?

I only ask because a 36 C&B cylinder should already be approx. .375, yet you are boring a 44 to accept tubing that has a .375 ID. Not trying to be smart, but it seems you have taken the long way around, so to speak

The original factory conversions utilized the original cylinder bored though with the back either cut off ala Colt style (conversion plate with a rebounding firing pin) or a soldered on rear extension ala Remington style. This is why they used heel based bullets.

HH

Greetings Hoof -
thanks for your thoughts -

I  currently have on hand only the one .36 Pietta Remington C&B cylinder that came with the revolver. The simple, and most structurally sound way to go would have been to call up the toy store and order another Pietta .36 C&B cylinder and have at it - lots of metal and simple as dirt :-) ...  I may still go that direction.

However, knowing that the early conversions were "bored thru" and wondering about the .45 conversions, it occurred to me that since I already have an extra  .44 Pietta Remington  C&B cylinder in somewhat sorry shape, I could make a lot more work for myself and get all kinds of recreation by doing it backwards . I think the Lahkota call it "Contraries" ....

So the experimental part of me began wondering, "how thin does it really get", and "what size tooling do I have?" and "gee, this 7/16 OD, 3/8 ID DOM seamless tubing seems to slide right into a .449-.450 cylinder mouth" ....

It is amazing how much trouble too much thought can get one into...

SOOOoooo I have bored the cylinder chambers to approx   .440 giving me a nice slip fit of the 7/16 (nominally .4375) tubing.  Even at .440 the bolt notches are remarkably thin. While working on the cylinder I was finally able to discerne... disearn... could tell that the bolt notches are supported by considerably thicker metal surrounding each nipple thread.

Now, I can face off the back of the cylinder leaving as much of the "star" as I need then silver solder the tubing in place. I am debating reaming the chamber in each tube section  prior to soldering or reaming in place after they are all installed. The former is a simple setup in a lathe, but offers the possibility of crushing the tubing whilst trying to hold it, and means I have to carefully align each tube during the soldering. The later requires either careful "dialing in" of the cylinder 6 times in a 4 jaw chuck, or a fabricating a stout fixture to hold the cylinder in the crosslide (or tailstock... )

The backplate seems relatively straightforward...

I may end up with just a pile of chips, but this is gettin' fun ...

yhs
Prof Marvel

[Hoof Hearted]

I would ream the cylinder first, then solder on the back plate and drill/ream that.
Then I would silver solder the "inserts" into the cylinder "assembly". Followed by facing off both ends in the lathe.
After that I would ream with a drill press (or even cordless drill) with the appropriate Chucking Reamer. This will save you a lot of lathe setup time.

I understand the whole process of working around things the long way

The thickness at the bolt stop notches should not be an issue since you are installing sleeves.

The bores can be straight through since you are shooting heeled bullets.

Have fun!
HH

[Professor Marvel]

Greetings John! thanks for your response

I'm mighty busy tonight and leaving for the weekend in the a.m. but will post this quick comment. The thin notches was a problem on the old Colt conversion and many antiques are broke through.

That explains quite a bit ... it seems I am recreating other peoples mistakes LOL.

So far with my conversion project on my 1860 Army I've went ahead and machined a 5 shot cylinder (.45 cal). I rejected modifying a cylinder because the walls would be far to thin and the notches would probably be open by the time it was to .480". But .38 is a different story and so is working on the Remington.  Seems like a lot of the same problems as my project. I did leave the overall diameter of my cyl. as large as possible.

Just to make the project more confusing, I have been measuring Colt model P Cylinders and Ruger Cylinders, and found that a .45 Colt will "just" slip into the .44 Remington frame, but of course the cylinder mouth is way out of alignment with the barrel. It appears that If I chose to fabricate a cylinder I could go to a somewhat larger diameter than the stock Pietta, which would certainly help if I wanted to do a .44 or .45, but in a .38 LC conversion it is really overkill.

On a Colt 1860, I have seen other folks machine the "step" in the frame away entirely, allowing a completely straight cylinder (non- stepped) rather like the "Open Top".

I wanted to know I have the best steel I could find and know what I had. I'm not sure what Pietta uses and that bothered me. You should be able to order a short length of quality steel online if you look a bit. Shipping and handling will probably be more than the steel.

I've considered converting to .38 and sleeve a stock cylinder as your trying. I actually wouldn't mind a .22 conversion using that method. 

(Ignore this part, I see on review you were asking about the notches when it's a .45 conversion) My initial thoughts are the sleeves should support the thin material in the notches. I would use 4130 aircraft tubing to make the sleeves. Kind of depends on if the walls on the sleeves are thick enough to handle 100% of the pressure. I don't know how to calculate the required wall thickness even after a long search for a formula. Seems ballistics isn't a hot topic in modern engineering books.

Actually we are both o n the same track - I fear I am continually confusing  things in this project by bouncing back and forth betwixt references to .38 and .44/.45 .  I do believe that the notches will be suitably supported by the tubing, especially with the BP pressures involved. Conversations with people who can actually do the engineering math have me convinced. One fellow did the numbers and showed me that a 4/40 scope mount screw hole that was bored through into a 30-30 chamber would cause no harm. The brass had enough support that with standard loads the brass did not even dimple. (He chose to be more conservative however, and low-temp soldered a screw in place, carefully polishing the chamber. )

Finding out exactly "what steel is appropriate" for cylinder fabrication is somewhat difficult. I will post anything I can find out. Whilst I regularly harden and temper a variety of self-made knives, chisels, and other tools,  I would rather not get into firearm heat treating. Except for Color Case Hardening ! oh-oh I seem to be thinking again....

But the BP pressures are not great, and we already know that the soft Italian steels hold up very well even if they do scratch easily... :-)

John and Hoof - I am going to try avoid confusing things with references to .44 and .45, and try to keep this project post focussed on the .38 Long Colt. It is for personal education, edification, fun, and a good reason to make chips with something useful at the end of it.   I do believe that from a practical  point of view, that Herr Kirst and the R&D folk have the science of the .45 conversions (and steels) down pat.

yhs, and thinking too much
Prof Marvel

[Professor Marvel]

Greetings HH!

I would ream the cylinder first, then solder on the back plate and drill/ream that.
Then I would silver solder the "inserts" into the cylinder "assembly". Followed by facing off both ends in the lathe.
After that I would ream with a drill press (or even cordless drill) with the appropriate Chucking Reamer. This will save you a lot of lathe setup time.

Ah , thanks HH - that assembly order simplifies matters greatly. I fear I have been overly influenced by Kunnhausen and his Accolytes- they would have everyone believe that one can only do chamber work using  a 5000 lb lathe accurate to .0000000000001"  in 10 feet. :-)

The bores can be straight through since you are shooting heeled bullets.

Oh-oh your making me think again :-)
I thought to try using my Lee .375 conicals, which have the tiny "heel" for chamber alignment, seated in  .38 sp case. I had originally thought to chamber "normally " with a ~.381 reamer, but then I would be trying to stuff a ~.375 + bullet into a .375 hole. You comment is greatly appreciated!

If the Lee conicals don't work out perhaps I will try my hand at lathe-cutting a mold, as an old gentleman just walked me through it. easy to say, we'll see how hard to do. more chips! 

[Hoof Hearted]

PM

Take a looksee at this link:

http://www.cascity.com/forumhall/index.php/topic,24196.0.html

Just buy a mould, sizing die and crimper from Bernie......

HH

[Long Johns Wolf]

Prof. Marvel: FWIW. my smith used 1.7225 - 42 CrM04 - V 320 steel to lathe the conversion cylinder for my Richards Conversion in .44 Colt cal.
Long Johns Wolf

[Professor Marvel]

> Just buy a mould, sizing die and crimper from Bernie......
> HH

Thanks Hoof Hearted, that makes it easy!

>Prof. Marvel: FWIW. my smith used 1.7225 - 42 CrM04 - V 320 steel to lathe the conversion cylinder for my Richards Conversion in .44 Colt cal.
> Long Johns Wolf

Vielen Dank' Mein Herr Wolf! Das ist genau was Ich brauche !!
Sie sind in Hofheim? Ich hab' drei Kollegen in Walldorf!
Halten Sie Ihr Pulver trocken.
Grüß
Prof. Marvel

[Skinny Preacher 66418]

Show pics of your progress 


So is using the stock .36 cal cylinder for a 38 conversion out the window? Would a hardness dimple test help with determining its strength?

[Professor Marvel]

Greetings Monsieur Preacher -
Thank you kindly for your continued interest and encouragement!
I have unfortunately been "Overcome by events" ... The bored out .44 cylinder and 3/8 ID tubing is sitting in my project drawer until I complete a sudden plethora of Home Improvement Honey-do's.  It is not forgotten, however, merely postponed temporarily. Whilst working on different House Projects I intend to sneak into my little shop now and then for further tinkering. If one wants tomatoes one must plant them at the planting time, not when one feels like it :-)
yhs
Prof Marvel

[Skinny Preacher 66418]

Better keep the wife happy.   

I'd like to see what you end up doing on the 38 conversion.