Mblmotors
Gold $$ Contributor
For sale NEW never used K&M Expand Mandrel Starter Kit for 6MM. $195.00 shipped CONUS
This is manufacturer’s suggested use page:
When using an expand mandrel to achieve final neck sizing bullet tension we find it best to size your neck 0.002” to 0.003” below your desired final bullet tension size. For example, say you are working with a 7mm caliber (0.284”) and you would like 0.004” of bullet tension. Subtract the 0.004” from the standard bullet diameter, 0.284”-0.004”=0.280”, this will be the final size after expanding. However, the neck inside diameter needs to be slightly smaller so the expand mandrel can properly size the brass. Now subtract the 0.002” or 0.003” from the final size, 0.280”-0.003”=0.277”. Now based on your neck wall thickness select the appropriate bushing that will achieve the 0.277” inside neck diameter. Once this sizing is complete perform the final sizing of the neck with the expand mandrel. Be sure to at least use a light lubricant. Alternatively, you can use a traditional full-length die (expander ball removed) and use the expand mandrel for final sizing.
This is manufacturer’s suggested use page:
When using an expand mandrel to achieve final neck sizing bullet tension we find it best to size your neck 0.002” to 0.003” below your desired final bullet tension size. For example, say you are working with a 7mm caliber (0.284”) and you would like 0.004” of bullet tension. Subtract the 0.004” from the standard bullet diameter, 0.284”-0.004”=0.280”, this will be the final size after expanding. However, the neck inside diameter needs to be slightly smaller so the expand mandrel can properly size the brass. Now subtract the 0.002” or 0.003” from the final size, 0.280”-0.003”=0.277”. Now based on your neck wall thickness select the appropriate bushing that will achieve the 0.277” inside neck diameter. Once this sizing is complete perform the final sizing of the neck with the expand mandrel. Be sure to at least use a light lubricant. Alternatively, you can use a traditional full-length die (expander ball removed) and use the expand mandrel for final sizing.
