detox
12-28-2013, 02:32 PM
My 686 Passed "Match" Range Rod Test according to Brownells instructions. Gun was manufactured around 1997. All else checks out OK except for slightly bent ejector rod...I will buy a new strait one from S&W
My 38/357 Match Range Rod measures .3459" diameter and has a 10/32 bolt hole tapped on end. I used a propeller shaft that is threaded 10-32 from one of my Fast Electric boats to hold rod for testing. A plus or minus .3460 pin gauge may work also if you have some way to hold it without getting stuck inside gun.
I allways wanted to know the diameter of the .357 Match range rod...now you know .3459" (measured with my .0001 micrometer). The "field" size range rod will be slightly smaller diameter for checking dirty test fired revolver at store before buying.
Match Rod also checks for any barrel constriction
I also checked chamber alignment with empty bell mouth case in each chamber...no snags using +.3570" pin gauge.
I believe most new and old revolvers will pass this test, but it is still good to know mine passed.
All cylinder throats measure equally .3575" So i must size lead bullets larger to .3580-.3585 to prevent gas cutting.
Forcing cone is a little rough, so i may polish cone slightly using a 7 or 8 degree brass lap. The laps only come in 5, 11, 18 degree angles, so i will have to cut one of the 18 versions to match the 686.
My 38/357 Match Range Rod measures .3459" diameter and has a 10/32 bolt hole tapped on end. I used a propeller shaft that is threaded 10-32 from one of my Fast Electric boats to hold rod for testing. A plus or minus .3460 pin gauge may work also if you have some way to hold it without getting stuck inside gun.
I allways wanted to know the diameter of the .357 Match range rod...now you know .3459" (measured with my .0001 micrometer). The "field" size range rod will be slightly smaller diameter for checking dirty test fired revolver at store before buying.
Match Rod also checks for any barrel constriction
I also checked chamber alignment with empty bell mouth case in each chamber...no snags using +.3570" pin gauge.
I believe most new and old revolvers will pass this test, but it is still good to know mine passed.
All cylinder throats measure equally .3575" So i must size lead bullets larger to .3580-.3585 to prevent gas cutting.
Forcing cone is a little rough, so i may polish cone slightly using a 7 or 8 degree brass lap. The laps only come in 5, 11, 18 degree angles, so i will have to cut one of the 18 versions to match the 686.