Looking for COL for Arsenal mold 312-145 LFN "Elvis" for 300 blk.

[tayous1]

Just received the mold yesterday and casted some Boolite today with the mold the Boolite came out looking great and going to powder coat them. I'm looking for a good COL to use this this with and AR. Thanks!

[Dusty Bannister]

You may want to start by seeing if the existing casting will fully chamber in the throat. With a larger body, you might also have a larger nose and that would prevent chambering at all. What are the bore and groove dimensions? Just stick the nose of the bullet into the muzzle if you can and see if it wobbles or does not enter at all.

[Hick]

Well-- with luck someone here will give you the exact COL if they know it. If not-- see if you can find any loads for a bullet with a similar nose shape (doesn't have to be exact) at about the same weight, and go with that COL. Also, as Dusty mentioned, you need to check to see if it will chamber. COL is mainly important for space inside the cartridge which affects pressure. But-- as long as you have a bullet shape and weight as a known one the space will be about the same also. Of course-- if you do it this way-- start with starting loads and work up.

[Dusty Bannister]

Once you have determined that the bullet nose will chamber, then you can use this very old method to get your answer for a custom bullet for a factory barrel and chamber.

Old method for finding best cartridge OAL

This is from one of the older reloading sources and I would suggest that you do this with every cast bullet and every fire arm and record those numbers. You have a custom mold, which sometimes has variation from cavity to cavity, and mold to mold, and then you powder coat for an added variable in thickness and coverage. Try this, find the shortest OAL for your guns of the same caliber, set your seat and crimp die, and you should be good to go. Shorten the seating depth slightly just to allow for added variables. Compare seating depth and perhaps re-work the load to be within safe pressures.


How to determine the cartridge OAL with a dowel or cleaning rod.

Cleaning rod/dowel method of finding cartridge OAL

This is what I use for my guns to determine the max OAL and this eliminates any question of the crimp, incorrect case prep, or other operator induced error.

This method works well on rifles and single shot pistols as well as Semi-autos. You can use a flat tipped cleaning rod, or flat tipped dowel rod. You will also need a sharp pointed pencil, a short dowel and a bullet sized but clean, of the type you are going to load.

For Rifles
Make sure the chamber is empty. Close the bolt, and be sure the firing pin is retracted into the bolt. Insert the dowel or cleaning rod and hold it against the face of the bolt. Mark the rod at the face of the muzzle. Remove rod, open bolt and remove it from the action. Insert the bullet into the breech and hold it snug into the rifling. While in that position insert the dowel or rod again, and with it firm against the nose of the bullet, mark the rod at the face of the muzzle.

The distance between the center of those two marks is the max cartridge OAL for that rifle, with that bullet sized to that diameter.

For Semi-auto pistols
Remove the barrel from the slide and make sure it is clean and free of leading or other debris in the barrel and chamber. The dowel or cleaning rod needs to be longer than the barrel. Hold the barrel, muzzle up, and place the barrel hood on a flat surface like a table top. Insert the dowel or rod from the muzzle and mark the rod exactly flush with the muzzle. Remove the rod and insert the bullet you intend to use into the chamber and lightly press and hold it in place with the short dowel. Place the assy muzzle up on the flat surface. Insert the rod/dowel into the muzzle so it rests on the nose of the bullet and again mark the rod exactly flush with the muzzle. Remove and set the barrel aside. The distance on the center of the two lines is the cartridge OAL. Seat a dummy round to this length, or slightly shorter and begin to apply the taper crimp until the dummy passes the plunk test. This is the optimum cartridge OAL length for this bullet in this gun.

You may need to adjust the seater to shorten the OAL if this does not feed from the magazine, but generally this will be a great fit. Remember, if you seat and crimp in one step, you might force a slight ridge ahead of the case mouth and that will screw up your seating.
Dusty

[tayous1]

Found a length that works when I get to a place that a rod I'll try that to give me a COL. I went with what I could find in several reloading manuals that I have as there seems to be a big difference when you get up to 150 gr bullets as most of them said 2.23 COL or about that but most of the 130-140 gr bullets said 2.055 so I set them 2.050-2.045 went out and all 10 fired with out a problem primers looked good also .

Boolite came out with range scrap and pure lead at the low point 143 gr and high 145 gr most where I'm the 144 gr area. Used 140 gr load date for it. Will be casting some more and seeing how accurate they are.