gamestalker
Regular Member
imported post
I've been reloading for over 25 years and recently learned something I betting most reloaders are unaware of and should take into consideration, especially regarding revolvers. Most of us I'm guessing that bullets with a canlure should be be seated using the canlure as the depth guide for the most part. However I've noticed that depending on the bullet, (I only load jacketed bullets) type and seating depth I'll get an excessive amount of pressures blowing back through the entire cylinder so much so that it will sometimes cause a near permanent imprint of the case head on the recoil plate and dislodge rounds from the case and,or, seat them deeper no matter how tight I crimp them. I couldn't find the cause for this until consulting with a person who is a certified expert regarding propellant physics. Apparently if the distance from the bearing surface of the bullet to the bearing surface of the cylinder lands is more than should be the magnum or heavy charges of slow burning powders will allow high pressure gases to escape past the projectile and out the front of the cylinder because seating depth and bullet design will leave a gap between the mouth of the case and the bearing surface of the cylinder. To eliminate this rather disturbing occurrence it is essential to seat as shallow as can be done without creating a chambering issue and still having some canelure to utilize for crimping purpose. I'm noticing the problem more so with the lighter projectiles in my .357 mag as the bearing surface of the bullet is either very short or non existent all together forward of the canelure. Another contributing factor is trimming my brass shorter than maximum specification which sets the bullet even further from the cylinder lands. I also noticed on that note that with the larger bullets, 158 grain, I'm getting near zero blow back because the bullet is contacting the cylinder lands while still inside of the case mouth giving the powder more time to finish its burn before becoming oxygenated by the free space or gap which is another good reason to try and eliminate as much free space or gap between case mouth and bearing surface during the powder burn.
When seconds count, the police are only minutes away!
I've been reloading for over 25 years and recently learned something I betting most reloaders are unaware of and should take into consideration, especially regarding revolvers. Most of us I'm guessing that bullets with a canlure should be be seated using the canlure as the depth guide for the most part. However I've noticed that depending on the bullet, (I only load jacketed bullets) type and seating depth I'll get an excessive amount of pressures blowing back through the entire cylinder so much so that it will sometimes cause a near permanent imprint of the case head on the recoil plate and dislodge rounds from the case and,or, seat them deeper no matter how tight I crimp them. I couldn't find the cause for this until consulting with a person who is a certified expert regarding propellant physics. Apparently if the distance from the bearing surface of the bullet to the bearing surface of the cylinder lands is more than should be the magnum or heavy charges of slow burning powders will allow high pressure gases to escape past the projectile and out the front of the cylinder because seating depth and bullet design will leave a gap between the mouth of the case and the bearing surface of the cylinder. To eliminate this rather disturbing occurrence it is essential to seat as shallow as can be done without creating a chambering issue and still having some canelure to utilize for crimping purpose. I'm noticing the problem more so with the lighter projectiles in my .357 mag as the bearing surface of the bullet is either very short or non existent all together forward of the canelure. Another contributing factor is trimming my brass shorter than maximum specification which sets the bullet even further from the cylinder lands. I also noticed on that note that with the larger bullets, 158 grain, I'm getting near zero blow back because the bullet is contacting the cylinder lands while still inside of the case mouth giving the powder more time to finish its burn before becoming oxygenated by the free space or gap which is another good reason to try and eliminate as much free space or gap between case mouth and bearing surface during the powder burn.
When seconds count, the police are only minutes away!