RCBS Quick Change Drop Tube Adapter Thread Size???

[ViragoSEPA]

I'm looking to drill and tap the discharge of my old Ohaus Duo Powder Measure to screw in the RCBS Quick Change Drop Tube Adapter (pic attached), then use the RCBS funnel quick change units with the o-rings. I believe the RCBS Quick Change Drop Tube Adapter is 5/8" x 18 TPI but would like to verify. Thank you!!!

[RedlegEd]

I'm looking to drill and tap the discharge of my old Ohaus Duo Powder Measure to screw in the RCBS Quick Change Drop Tube Adapter (pic attached), then use the RCBS funnel quick change units with the o-rings. I believe the RCBS Quick Change Drop Tube Adapter is 7/8" x 18 TPI but would like to verify. Thank you!!!

Hi, and welcome to CB!
I think you would be much further ahead to 3D print (or have someone do it for you for a small charge) an adapter that goes from your Ohaus to RCBS. I have both Powder Measures and the drop tube on the right in the picture below is for my Ohaus since the original drop tubes cracked and no longer fit tightly. I just made a 7/8-14 collar and then fashioned a drop tube to fit. It could easily be modified to accept the RCBS Tube Adapter. I believe the thread size for the RCBS Tube adapter is 9/16-16, but the TPI might be off a little. If you're interested in working on one together, send me a PM.
Ed

ETA: I just looked at it again and the easiest solution would be just 3D print a simple adapter that screws onto the Ohaus and the lower portion is the same ID as the RCBS which would accept the quick funnel change drop tubes with o-rings...no RCBS adapter needed!

[ViragoSEPA]

I made a mistake....I believe the thread is 5/8" NOT 7/8" x 18 TPI!!!

[ViragoSEPA]

I like the idea of 3D printing a direct adapter....let me check on that!
Thanks!

[RedlegEd]

I like the idea of 3D printing a direct adapter....let me check on that!
Thanks!

Hi,
Why screw up a perfectly good Ohaus Duo powder measure by trying to D&T for the RCBS when you could just make a simple screw on adapter? Like I said in my previous post, I had to make new drop tubes for mine, in addition, I designed and printed an adapter so it accepts the Lee Powder Measure hopper.
Ed

Ed