gunnut wrote:Here Ya go Wildcatter!Wildcatter wrote:Siringo wrote:
By the way -- during my range session today is made up some 45 gr. Lil'gun loads with a Hornady 230 gr. TC (encapsulated one). Ejected of fired cases was very weak, sometimes dumping the brass on the shooting bench and other times sending them out a couple of feet. I have sooting all the way down the case. Group size was more like a pattern. Could there be that much difference between the round nose and the TC? I don't think I was getting a good burn and 45 grs. is about all the case will hold. My OAL was 2.1 inches.
I repeat Gentlemen; most sooting usually is a function of not enough pressure. The question to ask, is why? Could be not enough powder, not enough bullet pull, or the powder burn rate is to slow, or the sum of all of these symptoms at the same time. Assuming everything else is safely reloaded to spec; these suggestions usually are the major culprits. Low pressures can cause the case not to seal in the chamber and can become so bad that the gases escaping down the sides of the case can cause the case to collapse from the side. I’ve never seen this in the 450, but it is always possible. A little sooting, at and around the case mouth is Normal and is seen in all rimless straight cases (45acp/9mm etc.). Using faster burning powders, ala, ‘lil gun/296 and others, usually keeps sooting to a minimum. AA1680, needs a stout crimp and allot of powder to seal properly, but then a little sooting can still be visible, but this should cause you no alarm and AA1680 has the additional benefit of driving the speeds up.
Something else about crimping vs. bullet creep, consider. Using a drill motor, I have chucked up the cutter of a hand held tubing cutter (every hardware store has them)and with a stone have nicely rounded off the sharp cutting edge. The cutter on the tubing cutter usually is held to the tool with a screw. Take the cutter out insert a longer screw; put a jam nut on the opposite side and you are now ready for the drill/lathe chuck. Any kind of stone will work; anything from one from the front yard or a chunk of cement, to something you buy from the hardware, just so long as it is on hard side. Now you have a nice little tool to roll a heavy crimp into the bullet at nearly any location you desire (Because we head space on the case mouth, you must stay well away from the case mouth. The crimp is best done towards the bullet base, but not on the base, bullet bases are critical to accuracy.) and is as good as any, so called standard roll crimp, something we cannot use at our case mouths. It will very slightly shorten the case length, so don’t get carried away. Keep the crimp fairly consistent, that is to say, location and pressure. Measure the final case length to see if you made it too short or have not put on enough crimp. Pull a couple of bullets and look to see if you have dented the bullet sides, you actually want this denting. This type of crimp is particularly useful when using solids. I put a groove into the solid at the spot I want to roll the crimp into, using this method. Lead based bullets do not need such a grove, as the crimp squeezes into the side of the bullet. Those long heavy bullets seem to thrive with this method of crimping, of course I still tapper crimp. After a little practice The Side Roll Crimp, as I am wont to call it, is easy to do and to keep somewhat consistent and accuracy is not adversely affected, even if you aren’t particularly consistent, yea even sometimes accuracy is made better.
Safety First…t
gunnut, I hope you don't mind that I fixed the quotes so that it's obvious what's happening in the conversation.
Nope don't mind at all, I need all the help I can get. This dissertation, from Cal-Guns, was one before I reveled my side crimp ideas using an altered LEE FACTORY CRIMP DIE. Thanks Gunnut, now we need the one I did about the LFC Die and our new readers will be well served and on the road to better..
it should work neat & sweet, and leave "four little ears" to headspace off of.