Reply to Thread

Message

<blockquote data-quote="Buzzdraw" data-source="post: 2684032" data-attributes="member: 385">Set up the bell/powder drop die, assuming same die used for both, if not the bell die, is a try to fit situation.&nbsp; Find some cases that are lengthwise close to the shorter dimension.&nbsp; Keep adjusting bell until it is a LITTLE belled, enough to allow easy entry of the bullet base.The crimp is a separate issue.&nbsp; Most semi-auto crimp dies are of the taper crimp variety, not the roll crimp.&nbsp; In general, think taper for semi-auto pistols and roll for revolvers.&nbsp; Taper crimp as well as roll is also a try, measure and adjust function.&nbsp; For taper crimp find some brass measuring on the thin end of mouth thickness; collect measurement.&nbsp; Now do some math.&nbsp; Add the measured mouth thickness X 2, plus measured actual bullet diameter (both down to .001&quot;).&nbsp;&nbsp; Now subtract .001&quot; for taper crimp.&nbsp; That&#039;s the measured number to work for, screwing your seat die in/out until your final test load round measures this goal number.&nbsp; Too little taper crimp = feeding malfunctions.&nbsp; Too much taper crimp = loss of accuracy.&nbsp; On the 40 S&amp;W the goal number I run with is .421&quot;.In some cases the .001 crimp allowance doesn&#039;t work well, as in 9 mm.&nbsp; It takes more (down to a .375 +.001&quot;) due to the relatively sharply tapered case.&nbsp; After you set for taper crimp or if you change bullets being loaded perform the bullet push in test on a loaded round.&nbsp; With moderately strong pushing hand pressure, push the nose of a loaded round against a solid object, such as the lip of your loading bench.&nbsp; If the bullet telescopes into the case increase the crimp slightly, then test again.&nbsp; The consequence of a bullet telescoping into the case on loading into a barrel is excess, possibly dangerous,&nbsp; chamber pressures.&nbsp; Personal injury and/or gun damage can be the outcome.If you don&#039;t own a set of 6&quot; metal calipers, get some.&nbsp; The imported dial-style can be had for as little as $25 or so.&nbsp; The electronic direct read-out are only a few bucks more.&nbsp; The really good ones will set you back over a C-note but aren&#039;t really necessary for most reloading applications.</blockquote>

[QUOTE="Buzzdraw, post: 2684032, member: 385"] Set up the bell/powder drop die, assuming same die used for both, if not the bell die, is a try to fit situation. Find some cases that are lengthwise close to the shorter dimension. Keep adjusting bell until it is a LITTLE belled, enough to allow easy entry of the bullet base. The crimp is a separate issue. Most semi-auto crimp dies are of the taper crimp variety, not the roll crimp. In general, think taper for semi-auto pistols and roll for revolvers. Taper crimp as well as roll is also a try, measure and adjust function. For taper crimp find some brass measuring on the thin end of mouth thickness; collect measurement. Now do some math. Add the measured mouth thickness X 2, plus measured actual bullet diameter (both down to .001"). Now subtract .001" for taper crimp. That's the measured number to work for, screwing your seat die in/out until your final test load round measures this goal number. Too little taper crimp = feeding malfunctions. Too much taper crimp = loss of accuracy. On the 40 S&W the goal number I run with is .421". In some cases the .001 crimp allowance doesn't work well, as in 9 mm. It takes more (down to a .375 +.001") due to the relatively sharply tapered case. After you set for taper crimp or if you change bullets being loaded perform the bullet push in test on a loaded round. With moderately strong pushing hand pressure, push the nose of a loaded round against a solid object, such as the lip of your loading bench. If the bullet telescopes into the case increase the crimp slightly, then test again. The consequence of a bullet telescoping into the case on loading into a barrel is excess, possibly dangerous, chamber pressures. Personal injury and/or gun damage can be the outcome. If you don't own a set of 6" metal calipers, get some. The imported dial-style can be had for as little as $25 or so. The electronic direct read-out are only a few bucks more. The really good ones will set you back over a C-note but aren't really necessary for most reloading applications. [/QUOTE]

Verification