ROA cylinder mods

[dickydalton]

I bought an inferior Classicballistx cylinder once. Edo Junker, of CBX, got me to return it to CBX. And then he and my cylinder disappeared.

 

[rodwha]

What I find funny about Richard's repeated statement about my bullet blowing up a walker is that he blames my bullet despite the fact that the gun in question was an ASM, a maker well known for having quality issues. But then he was there and knows every detail about what happened that day and can without a doubt blame me, though, if you followed the original threads in which this fellow was and became interested, you'd note that I state this bullet was designed for a ROA that I have no doubts could handle the larger bearing surfaces. But don't let facts get in the way...

Since he is such great friends and was there I suppose he'll mention how I gave him all sorts of load data too.

 

[dickydalton]

I asked you a question about him before that got deleted so I guess we'll never know who he's friends with. :idunno:

 

[M. De Land]

I'm still wondering where they could remove enough metal out of a Ruger chamber to gain ten grains of 3F.
I think that may be an exaggeration but can not prove it.

 

[Zonie]

Without showing how I calculated it because I know many of you get tired of seeing that math manure, in a .454 diameter chamber, it's depth would have to be increased .2521 inches to increase the volume 10 grains.

For you math haters, that's 1/4 inch.

I haven't seen a Ruger OA cylinder but I would think increasing the chambers depth 1/4 inch would pretty much wipe out all of the nipple threads.

Maybe I'm wrong? :hmm:

 

[M. De Land]

Thanks Jim, I often have to call on my engineer friends to help me where math challenged.
I appreciate that "manure" you jest about as it is bases for just about all we do with any precision involved.
I'm pretty certain that amount of volume increase is horse pucky.
Great write up on the nipple removal from the 62 police.
Did you ever get back any of your stolen guns?
I never have mine.

 

[rodwha]

I believe it is Clements who deepens the chambers. I'm not sure what they claim the gain is.

Ballistix claimed a gain of 5-10 grns, and I'm wondering if it's dependent on type of powder. I can get 45 grns of 3F Triple 7 with a ball in my ROA. But when I tried that with 3F Olde E I had to shave the end of the ball off. It only takes about 40 grns.

Pyrodex also seems to compress a good deal as well.

So maybe it's only ~1/8" deeper. And then I suppose it's also dependent on the powder measure's measurements.

 

[M. De Land]

I think if one absolutely must have more powder than a safer way to go about it would be to stage compress powder rather than removing cylinder steel.
It probably should be discussed for some reference in how it's done.
I have not tried it personally and would not recommend it in general but feel it would be safer than reaming out chamber steel.
It is probably safe when only used with black powder and round balls in modern steel reproduction guns.
It goes something like this.
Dump a third of the total charge one intends to use and with the aid of a wood dowel of appropriate size compress the first powder drop with the rammer.
Same deal with the next two until the third is compressed and now the ball is seated. Black powder does not compress evenly all the way back in a chamber so it is possible to get more in with stage compressing.
A ball should be light enough to keep you out of trouble pressure wise but I believe this method far less dangerous than letting some one ream out cylinder chamber steel if you simply must have more velocity from your gun.
I do not use nor recommend the practice but think it should be talked about.

 

[rodwha]

I doubt Clements would do such a thing if it were even a little bit iffy, and we haven't heard of one letting go.

Look at the wall thickness of many of the repros, and then look at the depth of the threads. Being much thicker I'd not think it detrimental, but then I'm not familiar enough to say that it's not necessary to be twice as thick in the end. And repros, such as my Pietta Remington '58, have had the thin cylinder walls reamed a little larger and we haven't heard of one of them having a failure either.

I don't have a need to such. I feel 35 grns of 3F Olde E or T7 is plenty for what I'd want to do.

 

[M. De Land]

It's my opinion that no more chamber metal should be removed from the bottom than the full threaded shank length of the appropriate nipple that is used in it.

Diameter reduction should not be used at all as the metal is thin enough already under the bolt notch.
I still think powder stage compression would be a safer bet than chamber steel reduction as this is were the safety margin is engineered.

 

[dickydalton]

I'm thinking that Old Edo Junker and his merry band used 1F to con a lot of people. I used Swiss 3F and the ROA cylinder held more. :cursing:

 

[M. De Land]

You will get more powder in with 3F than 1F which is much coarser.
Perhaps you meant 4F or Null B.

 

[dickydalton]

That coarser powder compacts more.

 

[Claude Mathis]

Since the original post says, "I'm aware of the classicballistx site that sells new precision cylinders but I don't want that.", let's leave classicballistx out of this discussion. It is off topic.

 

[M. De Land]

No, it does not. The larger the grain size the more air there is between each grain and the less weight of powder the chamber will hold.
The smaller the grain size, the denser the charge weight (less air more powder) and the more powder that can be contained.
Same reason staged compression allows more powder to be loaded. The air space between grains is more thoroughly removed.
Side note, remember BP does not need air between grains to burn, it contains it's own air with in it's make up( potassium nitrate).

 

[gl1200a]

The deepening Clements does, does not extend into the nipples threaded area.
Here is a stock ROA cylinder, notice the how the bottom of the cylinder is made.

Here is a Clements deepened cylinder

I am a fan of David Clement's work. I bought a rough 7 1/2" stainless ROA to have made into exactly what I wanted for carry in the woods. This is it after it was shortened to 5 1/2" taller front sight and deepened cylinders. I have not chronographed this gun with a stock cylinder. But with the deepened cylinder, with 3F Swiss, throw a roundball at 1100 fps.

The cylinder deepening allows for 5 more grains of powder vs the stock cylinder.

 

[rodwha]

Very nice looking! Like the dark wood grips!

Is 1100 fps using 45 grns of 3F?

 

[Zonie]

Your 1100 fps beat Lyman's ROA by 24 fps. :grin:

Lymans "BLACK POWDER HANDBOOK & LOADING MANUAL" 2nd ed shows them getting 1076 fps with 40 grains of GOEX 3Fg powder under a .457 diameter roundball.

They were shooting a standard 7 1/2" barrel pistol.

 

[hawkeye2]

gl1200a thanks for posting those excellent photos of Dave's work. Five grains of 3f is a significant increase. Your post answers a lot of questions and 1100 ft./sec. is impressive.

 

[rodwha]

Mike Beliveau got 1011 fps with a 5.5" barrel and 1062 fps from a 7.5" barrel and a ball using 33 grns of 3F Triple 7. Curious what 40 grns would show.
https://www.youtube.com/watch?v=LP_dwo2nThA