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robertbank
07-28-2021, 10:35 AM
After my old 41 Long Colt New Navy 1892 encountered a cracked forcing cone I had my gunsmith rebuild the gun into a 38spl using a .357 new barrel and a cylinder from a 38 Long Colt. The gun is now functioning better than it ever did in it's former dress, however the new cylinder has rather large cylinder throats. Three are at least > .374".

While the gun is capable of excellent accuracy I am getting significant leading in the first half inch of the barrel. I attribute this to gas cutting. I am usiong very light 38spl loadings ie 3 gr of 700x under a .358 SWC -Lyman 358477 bullet. cast from WW.

I am thinking casting the bullets out of pure lead might help along with applying GC's to the base of the bullets. I hope I am not barking up the wrong tree here but look to you guys for guidance.

This revolver is deemed to be an antique up here and is not considered a firearm under our Criminal Code. I think our definition of an "Antique Firearm" is the same as yours in the US. Because of it's status I am limited to what I could do to retain it as an antique.

Thoughts/

Take Care

Bob
BTW because it is an antique by definition our stupid gun laws do not apply to it which makes the gun rather valuable up here as an antique.

Beagle333
07-28-2021, 10:54 AM
Boolit coatings would probably help too...... either PC or Hi-Tek or some such.

gpidaho
07-28-2021, 11:32 AM
robertbank: I would consider having Tom at Accurate molds cut you a healed bullet mold and cast your bullets of soft lead and powder coat them. Gp

robertbank
07-28-2021, 11:57 AM
robertbank: I would consider having Tom at Accurate molds cut you a healed bullet mold and cast your bullets of soft lead and powder coat them. Gp

There is an idea I never thought of. I even have an insert I used for loading 31LC heeled bullets that would work for 38spl.

Thanks for the suggestion. I am also going to PC some bullets to see how that works out.

Take Care

Bob

O

Texas by God
07-28-2021, 06:42 PM
Aren't .38 Long Colt cylinder chambers bored straight through with no throat- for the heeled bullet? I seem to recall having an army special Colt .38 that would accept .357 brass. And a Spanish sort of copy of a S&W DA revolver that was the same way.
Memory is tricky, though.

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DougGuy
07-28-2021, 07:43 PM
what do the chambers measure at the case mouth?

robertbank
07-28-2021, 11:22 PM
Aren't .38 Long Colt cylinder chambers bored straight through with no throat- for the heeled bullet? I seem to recall having an army special Colt .38 that would accept .357 brass. And a Spanish sort of copy of a S&W DA revolver that was the same way.
Memory is tricky, though.

Sent from my SM-A716U using Tapatalk

Like t6he old 41LC cylinder they are bored straight through. I have no history of where or what, if anything has been done to the throats. I think the idea of using a heel based bullet is it would allow for a larger diameter bullet than othrwise would be possible.

The cylinders will take sized 38spl with ease. I measured an unsized used case at .374 and it was able to penetrate four of the cylinders with a bit of room left over. Iddly enough it seemed to be tighter in the rear entrance than the throat..

Here are the throats as measured by my calipers.

#1 .365
#2 .369
#3 .374
#4 .377
#5 .371
#6 .377
A spent 38spl case measured out at .378 and entered each cylinder with ease. Not sloppy but not tight either. Viewed from the rear each cylinder has a very small but noticeable step indicating a bit of a throat does exist. I am pretty much tied up for the Next couple of weeks so I won't be able to get the gun down to my 'smith until mid August. He can do some precise measurements. All I have is a set of calipers and I am not very good at this sort of thing anyway.

I suspect I will have to get a mold made to fit the largest cylinder if I am to be able to end my leading woes with the gun. Accuracy wise the darn gun shoots. It just leads up rather quickly at the start of the rifling.

Thoughts?

Take Care

Bob

Mk42gunner
07-28-2021, 11:38 PM
Having the boolit fit the throats sounds all well and good, until it needs to be sized down ten to twenty thousandths of an inch upon firing. I cannot imagine that is good for the longevity of the gun, even with light loads.

I would look for another cylinder that can be fitted with appropriate sized throats. Didn't Colt make some of those guns in .38 Special? Maybe the dimensions of those would be better?

Robert

robertbank
07-28-2021, 11:47 PM
Finding such a cylinder becomes the issue then. My 'smith scours his usual US sources and got lucky with this one. I may also just powder coat my bullets and run with them. The gun has a new fitted .357 barrel made form a rifled blank. The gun shoots..just leads up.

Take Care

Bob

oley55
07-29-2021, 10:56 AM
robertbank: I would consider having Tom at Accurate molds cut you a healed bullet mold and cast your bullets of soft lead and powder coat them. Gp

at the risk of hi-jacking this thread, how does one size a healed bullet? Just wondering how that works.

gpidaho
07-29-2021, 11:10 AM
oley55: Tom at Accurate offers the moulds cut to specific measurements. You can +or+ thousandths where you need to for the perfect. It's up to you to get these measurements correct for your casting alloy. If I were to size a healed bullet, I would use a push through die or bushing and size base first. I do see your point though. Depending on the bullet it might be hard to keep perfectly centered. Best to get the measurements right so the bullet can be used "As cast" Gp

robertbank
07-29-2021, 11:43 AM
at the risk of hi-jacking this thread, how does one size a healed bullet? Just wondering how that works.

You don't is the short answer, or at least I never bothered to do so with the 41LC.

Seating them with a crimp was an issue. Despite what the "technician" said a Lee's (he claimed Lee had never made nor could they a crimping die for the 41LC) I managed to acquire a Lee crimping die for the 41LC. Prior to getting the Lee crimping die I ran the cartridges through a sizing die whch did squeeze the bullet and brass enough to "crimp" the bullet into the case.

I may put my molds and loading dies up for sale here in due course.

Take Care

Bob

Harter66
07-29-2021, 11:51 AM
At the risk of tired advise ........
Match the throats in this case .374 might be best here .
Size to the throats . For a std mould something on the order of a fat 9×18/9mm Mak might serve well .

A more sensible plan might be to locate a HB WC mould as cast in AC50/50 or pure should resolve the dia issue . Likewise there is a HB RN but i don't recall number .

oley55
07-29-2021, 01:39 PM
oley55: Tom at Accurate offers the moulds cut to specific measurements. You can +or+ thousandths where you need to for the perfect. It's up to you to get these measurements correct for your casting alloy. If I were to size a healed bullet, I would use a push through die or bushing and size base first. I do see your point though. Depending on the bullet it might be hard to keep perfectly centered. Best to get the measurements right so the bullet can be used "As cast" Gp

when I looked up heeled bullets ( https://en.wikipedia.org/wiki/Heeled_bullet ) the diagrams and description said the base of the bullet that fits into the case is smaller than the nose of the bullet. Quote from Corbin: "Heel-type bullets have a reduced base portion that fits inside the cartridge case." In other words the loaded round has the same bullet/case mouth diameter.

Are there different types?

robertbank
07-29-2021, 01:41 PM
when I looked up heeled bullets ( https://en.wikipedia.org/wiki/Heeled_bullet ) the diagrams and description said the base of the bullet that fits into the case is smaller than the nose of the bullet. In other words the loaded round has the same bullet/case mouth diameter. Are there different types?

No, that description is correct.

Take Care

Bob

gpidaho
07-29-2021, 01:46 PM
oley: Wikipedia is correct in their explanation of a healed bullet. Gp

Mk42gunner
07-29-2021, 02:07 PM
For a look at a still loaded heel type bullet, look no further than your nearest .22 Long Rifle round.

Robert

Wayne Smith
07-30-2021, 08:54 AM
Bernie at Old West Bullet Molds will modify a Lee crimp die to crimp heeled boolits. For any question concerning heeled boolits Bernie is your go to guy.

44magLeo
08-07-2021, 04:11 PM
Pehaps using a piece of barrel for a 375 bore, then reaming all the cylinders to match that bore is an option. Then use bullets sized to match the new bore.
This may work with 38 cases or maybe cut back 30-30 cases to make a 375 Winchester short.
Just a thought that came to me.
Leo

DougGuy
08-07-2021, 04:31 PM
Ok now let me throw a wrench into the works.. Suppose you had a Lee collet crimp die for 41mag, or 44 special, whichever caliber that would be close to the OD of the loaded round, and you make a new collet to go inside the die body, where the typical collet crimp die only crimps a tiny band up at the case mouth, supposed you made one with a longer crimp band, let's say .200" or .250" or ever how long the heel is that sticks in the case, and you make the inside diameter of the collet just snug enough that it works with one headstamp so you could make it work just like you need it, and you make the length of the collet stop just at the case mouth, you would have a heel only crimp die that wouldn't reduce the diameter of the boolit ahead of the case.

quasi
08-08-2021, 08:54 PM
Have all your cylinder throats bored out to the same size, and have bushings made and installed . Dlask could do it.

robertbank
08-08-2021, 11:11 PM
Unless there is NO alternative playing with heel based bullets is the original PITA. I'll put up with the leading before I go heel based for essentially a 38spl now. I am going to set up my powder coating gun latter next week and PC some bullets and load them up. I also have the option of putting GC's on the bullets which might help with the leading as well. To assist even further I may try casting some pure lead bullets and see if they will obuterate enough to end the gas cutting. I will beagle the milds to see if I can get them to drop out just a tad bigger in diameter/

Thanks to all who replied.

Take Care

Bob

Wayne Smith
08-09-2021, 07:12 AM
You don't is the short answer, or at least I never bothered to do so with the 41LC.

Seating them with a crimp was an issue. Despite what the "technician" said a Lee's (he claimed Lee had never made nor could they a crimping die for the 41LC) I managed to acquire a Lee crimping die for the 41LC. Prior to getting the Lee crimping die I ran the cartridges through a sizing die whch did squeeze the bullet and brass enough to "crimp" the bullet into the case.

I may put my molds and loading dies up for sale here in due course.

Take Care

Bob

Bob, Lee did not make your die as it is. Bernie at Old West Molds modifies the Lee die to crimp heeled boolits. So Lee doesn't know about it/won't claim it.

robertbank
08-09-2021, 09:05 AM
Bob, Lee did not make your die as it is. Bernie at Old West Molds modifies the Lee die to crimp heeled boolits. So Lee doesn't know about it/won't claim it.

Ah, that explains it. I owe Lee an opology due to my "Mind" thoughts, but then again I have two push thru Lee dies -.357 & .358 - that both size bullets the same diameter so I will hold off on the mental opology. :>)

Thanks for the info.

Take Care

Bob