Shooting Cast Bullets In The 480 Ruger - A Fix For Ringing

[DougGuy]

Shooting cast bullets in the 480 Ruger can have some problems. SAAMI specs (and Ruger) call for a rather abrupt 45 degree step which transitions into the cylinder throats. This can cause the chambers to shave off a "ring" of lead from the bullets as they are fired, and after a few rounds, will prevent chambering of fresh ammo.

To cure the problem, I had Clyde at Manson Reamers make me a custom finishing reamer on my own specs with the more typical 6 degree 30min angle so that the chamber will have a more traditional chamfer and facilitate the use of cast bullets without ringing the chambers..

Here are some pics. You can see in the first pic, a stock 480 Ruger cylinder with the very abrupt angle, the rest of the pics are this same cylinder after reaming the chambers to remove that sharp angle and change it into a much easier transition from case mouth to cylinder throat..

BTW, the throats in front of the chamfers were honed with the Sunnen hone to make them a consistent .4782" so I could use a .478" pilot on the nose of the reamer. This insures the chamfer is concentric to the throat. You want the tightest fit you can achieve with the pilot for the best results.

The last pic is a dead stop that I machined from tool steel to insure consistent depth and conformity.

 

[Enigma]

I like it! Unfortunately, it'll be a while before I can put my hands on my .480 again, and send you the cylinder.

 

[contender]

Nice. I may just have to send you my 480 cylinder as well. I use powder coated bullets,,, and I will have to see if I get a ring of lead from them.

 

[Johnnu2]

FABULOUS photography..... just amazing to me..>!!
J

 

[foxtrapper]

Doug sending you a pm. Got a couple 480 cylinders

 

[mike7mm08]

Was there any practical reason for how the cylinders were factory machined? Does this detract from that at all? Any effect negative or positive when shooting jacketed bullets after your procedure?

 

[DougGuy]

Was there any practical reason for how the cylinders were factory machined? Does this detract from that at all? Any effect negative or positive when shooting jacketed bullets after your procedure?

That you would have to ask Ruger about. I have no idea why they would machine a step like that, obviously they only intend jacketed bullets to be used, and the jackets would have to be rather thick to prevent obturation. I have not had a jacketed bullet range report after this procedure. The customer I did this for only shoots cast and he was having issues ringing the chambers.

 

[riddleofsteel]

Let me put in a plug for Doug here. Top notch gunsmith. I learned tons about my revolvers and loading cast lead bullets from him, in person and by messages.

All my Ruger single actions are shooting SOOOO much better since he worked on them.

 

[DougGuy]

I courteously ask for ppl to send a PM for details. Thanks! Doug

 

[gcf]

Great service, & fast turn around!

 

[NikA]

FWIW, SAAMI specs dictate the steep factory cylinder throat transition angle in .480 Ruger chambers. Looking at a few of the specified transition angles for various cartridges, low angles like 6°30' seem to be the norm for small caliber low pressure cartridges like 38 Special and 32 S&W; larger bore higher pressure cartridges have steeper angles in the 12-20° range.

IIRC, the .480 Ruger throat transition angle matches that specified for .454 Casull, another very large bore/very high pressure cartridge. I believe that the shallow angle is probably appropriate for low pressure cast bullet loads; I'm not sure how they will work with higher pressure loads the cartridge is intended for.

 

[Ale-8(1)]

Bump.

 

[DougGuy]

FWIW, SAAMI specs dictate the steep factory cylinder throat transition angle in .480 Ruger chambers. Looking at a few of the specified transition angles for various cartridges, low angles like 6°30' seem to be the norm for small caliber low pressure cartridges like 38 Special and 32 S&W; larger bore higher pressure cartridges have steeper angles in the 12-20° range.

IIRC, the .480 Ruger throat transition angle matches that specified for .454 Casull, another very large bore/very high pressure cartridge. I believe that the shallow angle is probably appropriate for low pressure cast bullet loads; I'm not sure how they will work with higher pressure loads the cartridge is intended for.

Well, they cleaned house at the forum and I just now got back on.

In response to the angle, Ruger never intended on users shooting cast bullets or boolits in the 480. It is chambered for the sides of the jacketed bullet to go snugly into the throat so it is held in alignment for firing. This works pretty well, UNTIL you go to shooting lead boolits which will under the pressure of firing, begin to obturate to the throat walls as it leaves the case mouth, and the abrupt angle at the end of the case mouth will shave off rings of lead from the sides of the boolit and in short order will foul the chamber to the point that it can't be reloaded until the lead rings are removed.

The chamfer serves to eliminate the sharp ledge and provides a more typical angle seen in the majority of straight walled revolver calibers. I wouldn't consider the 357, the 44 magnum low pressure cartridges by any stretch of the word, and the chamfers work well for both jacketed and cast boolits in those calibers.

I don't personally own the 480, but I have reamed the abrupt ledge out of quite a few of them so far, and I have not yet had a negative review or complaint come back to me after the reaming operation is done and the chamber is now more suited to shooting cast boolits, so I know it works. Jacketed bullets have a soft lead core swaged into a gilding metal jacket, and they will very happily negotiate the chamfer on firing, same as a 44 magnum does.

 

[BigBoreOr]

I have a 475 Linebaugh/ 480 Ruger BFR and I am curious if you have any knowledge if this would apply to that gun? It is a new model made in 2022