Shooting Cast Boolits In The 480 Ruger - A Fix For Ringing The Chambers

[DougGuy]

Shooting cast boolits 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 boolits 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 boolits 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.

[Earlwb]

That is a nice idea and I like your method. I am surprised that they put a sharp shelf or edge in the chambers like that too.

[tja6435]

Very nice. Makes me want to take on a .480 as funding allows.

[9.3X62AL]

Night & day difference between the before & after appearances of the throat transitions. Gotta wonder what Ruger was thinking about with the 45* transition. Another example of "Jacketed-bullet bias" when it comes to interior dimensioning of firearms, I suppose.

[Dale53]

DougGuy;
Thanks for the tutorial! Great photos, too!

Dale53

[Iron Whittler]

Dougguy, is this an issue with all calibers of ruger super red hawks? 454 casull, 45 colt? I am very pleased with the throat job you did on my S&W500 Mag!! A straight shooter and a Craftsman for sure.

[sixshot]

Nice photo's, thanks!!

Dick

[Thumbcocker]

Beautiful machine work.

[Paul_R]

Nice work!

[DougGuy]

Dougguy, is this an issue with all calibers of ruger super red hawks? 454 casull, 45 colt? I am very pleased with the throat job you did on my S&W500 Mag!! A straight shooter and a Craftsman for sure.

Thank you for the kind words sir. Afaik, the 454 and 45 Colt RH have the conventional 6 degree chamfer. I can't recall seeing a sharp transition like the 480 has in any of the other big bore calibers for the RH.

[Greg G]

Good to see a craftsman post his work here. I started reading your post without looking at your name and when I got to the word Sunnen I realized I was reading the words of a machinist. I have Sunnen tools in my head porting shop (valve guide and lifter bore hones).