scruffy
Member
New to me 629-6 and first .44 mag. It was only shot a handful of times. On forums, I was advised in several posts to measure the cylinder throats as they are commonly tight on newer guns. I used a inside digital calipers but got too much variation. I bought a few Vermont Pin Gauges in .426"-, .427"-, .428"- and .429"- to obtain accurate readings.
The .428"- drops right through by gravity when inserted from the front or rear. The .429" was a tight fit in the throat area. Was very difficult to press in from the front. Angle had to be just right and had to wiggle a little and apply a lot of hand pressure. When inserted from the rear they went in but when they reached the throat needed to be tapped with a dowel to get them to pass through. I repeated this multiple times for each chamber and kept the chamber and pin gauge well lubricated with gun oil. The .429"- is basically a press fit, (see pic). I can now put the .429"- from both ends with thumb pressure.
When I cleaned up after measuring I noticed a lot of light scratches in the throat that I don't believe were there before. The edges of the pin gauges are smooth with no burrs and the chambers were clean as I could get them before measuring.
Did I ruin the throats of the cylinder? Would those scratches impact accuracy? Don't want to ream them as they are .429" the factory jacketed bullets I shoot are also .429" or slightly less (Winchester and Magtech). Mad at myself for not seeing this as I was measuring. I'm an idiot.
The .428"- drops right through by gravity when inserted from the front or rear. The .429" was a tight fit in the throat area. Was very difficult to press in from the front. Angle had to be just right and had to wiggle a little and apply a lot of hand pressure. When inserted from the rear they went in but when they reached the throat needed to be tapped with a dowel to get them to pass through. I repeated this multiple times for each chamber and kept the chamber and pin gauge well lubricated with gun oil. The .429"- is basically a press fit, (see pic). I can now put the .429"- from both ends with thumb pressure.
When I cleaned up after measuring I noticed a lot of light scratches in the throat that I don't believe were there before. The edges of the pin gauges are smooth with no burrs and the chambers were clean as I could get them before measuring.
Did I ruin the throats of the cylinder? Would those scratches impact accuracy? Don't want to ream them as they are .429" the factory jacketed bullets I shoot are also .429" or slightly less (Winchester and Magtech). Mad at myself for not seeing this as I was measuring. I'm an idiot.



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