627 Cylinder 9mm Conversion

[Maxw]

Being cooped up with the virus mess I remembered that I had a 627 takeoff cylinder from an old friend's revolver. I fit a blued ejector rod assembly, checked that cylinder timing on my ICORE match 627, reamed the chambers with my 9mm finishing reamer and off to the range I went. In VA gun shops and shooting is allowed if social distancing guidelines are followed. Cast PC coated .356" bullets exhibited yaw at 15 yards, 115 JHP were OK but shot low. Loaded up some Bear Creek Supply .358" 158gr RN bullets loaded to 1.170" OAL and those had the same basic point of impact as my ICORE match 38LC loads. Now off to developing loads that meet power factor. Now I have a dual caliber 627.

 

[Maxw]

I have finished my load development w/o chronograph data due to limited range access. I shot groups at 25 yards and 50 yards using a rest from the bench DA only. There was some wobble due to 72 year old hands and eyes but illustrate what I achieved. Bullets were 158 gr RN lead used in 38LC brass, 158 gr RNFP bullets with no grease groove, and a 124 gr XTP used for 9mm. There was yaw in bullet holes for the the 158 gr 9mm loads at both distances with arrows highlighting elongated holes. The 158 gr RNFP load would be suitable for ranges at 25 and closer ranges but not for ranges beyond 25 yards. There was no observed yaw with the XTP loads. I suspect that 147 gr jacketed 9mm bullets would also perform well. 

This has been a great shelter in place project and now I have a 9mm revolver again.

 

[mikerjf]

Thank for the report. Any issues with bullet sticking or case splitting?

 

[Sevens]

Are you using moon clips or punching each empty out with a pencil or some other method?

 

[Maxw]

Hundreds of rounds fired with no bullet sticking or split cases. I used Revolver Supply moon clips.