Arsenal Mold 454424 230 Gr SWC COAL?

[billmc2]

Does anyone else use this mold? I'm using it for 45 ACP. I'm using it in a Sig P220. I'm trying to learn the process of deciding on an overall length or stated a different way, how deep into the case to place it.

My first go at it, I had an overall length of 1.230". It was a little tough getting the rounds into the magazine. They shot OK but were a little slow. It then dawned on me that I needed to seat the bullet deeper to fit the magazine. After realizing I had them to long, I shortened them to 1.210". These easily fit into the magazine and they also seem to shoot OK, they are faster but they are still running slow.

I am using load data from the 2nd edition of Lee's Modern Reloading for a 230 gr lead bullet using Accurate No 5. This is on page 256. For both Accurate 5 and Accurate 7 the min OAL is stated to be 1.230, while the majority of other powders indicate min OAL of 1.200. The book does not specify what specific bullet is being used; just Lead Bullet.

I haven't found the barrel length that Lee used but he does say the data comes from the powder companies. On Hodgon's website they indicate a 5" barrel, my Sig has a 4.4" barrel. My starting velocity is 22 fps slower than what the data calls for while the max velocity is 83 fps slower. I don't know (but think) my velocity should be a little higher than it is. Because of that, my conclusion is that the bullet isn't seated deep enough. I don't know if I'm correct or not. My brass is already covering the bullet's crimp groove.

How do you go about determining what the cartridge length should be?

[dondiego]

Does anyone else use this mold? I'm using it for 45 ACP. I'm using it in a Sig P220. I'm trying to learn the process of deciding on an overall length or stated a different way, how deep into the case to place it.

My first go at it, I had an overall length of 1.230". It was a little tough getting the rounds into the magazine. They shot OK but were a little slow. It then dawned on me that I needed to seat the bullet deeper to fit the magazine. After realizing I had them to long, I shortened them to 1.210". These easily fit into the magazine and they also seem to shoot OK, they are faster but they are still running slow.

I am using load data from the 2nd edition of Lee's Modern Reloading for a 230 gr lead bullet using Accurate No 5. This is on page 256. For both Accurate 5 and Accurate 7 the min OAL is stated to be 1.230, while the majority of other powders indicate min OAL of 1.200. The book does not specify what specific bullet is being used; just Lead Bullet.

I haven't found the barrel length that Lee used but he does say the data comes from the powder companies. On Hodgon's website they indicate a 5" barrel, my Sig has a 4.4" barrel. My starting velocity is 22 fps slower than what the data calls for while the max velocity is 83 fps slower. I don't know (but think) my velocity should be a little higher than it is. Because of that, my conclusion is that the bullet isn't seated deep enough. I don't know if I'm correct or not. My brass is already covering the bullet's crimp groove.

How do you go about determining what the cartridge length should be?

Look up "Plunk test". Basically, the loaded round must fall into the barrel up to the same level as a good factory round. That usually means that the case rim is flush with the barrel hood. It also has to fit in the magazine too.

[billmc2]

Look up "Plunk test". Basically, the loaded round must fall into the barrel up to the same level as a good factory round. That usually means that the case rim is flush with the barrel hood. It also has to fit in the magazine too.

Maybe I asked the wrong question or asked it in the wrong way. My understanding of a plunk test is to assure that the cartridge fits within the chamber and the cartridge isn't to long. My cartridges are fitting within the chamber just fine and they are shooting. Because I'm not getting the expected velocity from them, I'm thinking my cartridges are to long. I understand that if pressure goes up then velocity should also go up. Without increasing the powder charge, they only way I can think of to increase pressure (thus velocity) is to decrease volume within the case by seating the bullet deeper. I don't know how deep I can seat the bullet without going over pressure and creating an unsafe situation.

I also don't know if the velocities I am currently getting are what they should be for the shorter barrel. If the velocities are where they are supposed to be, then I guess what I've got right now is correct. I thought, as a generality, that for each inch of barrel reduction you loose approximately 50 ft/sec. At the highest charge, I'm loosing 86 ft/sec for a 0.6 inch reduction.

[dondiego]

Seat your bullets a sixteenth of an inch and shoot some. How were they? If they are still seeming to be too low in velocity then it is time to increase the powder charge. Go slow!

[rockrat]

Have you checked the weight of the boolit? Just because it says 230gr, doesn't mean its going to cast at 230gr. IIRC, my Arsenal mould casts closer to 237gr with my ww/iso alloy.

[billmc2]

Thanks for the weighing suggestion, I hadn't thought about that.

I just weighed a sample of 5 powder coated bullets. None were 230 gr, they were all light. The heaviest was 228 gr and the lightest was 227.

[DocSavage]

If you're expecting the same velocities as a reloading manual you going to be disappointed or excited. Every firearm is a law unto itself due to various machining process variations in the alloy of the firearm,powder,internal capabilities of the brass you're using ad infinitum. Most bullet makers fire their loads out of a pressure barrel that's made to very tight tolerances. To quote a line from a Speer manual this is why Ballistian get gray hair

[billmc2]

Thanks Doc, I was not looking for exact velocities, I knew they would be different but I didn't expect the amount of difference I saw.

I am now thinking my loads are just fine the way they are. I have a problem with either the gun or the chronograph. Of factory loads I have on hand, I just shot 30 rounds. They were all 230 gr, 10 rounds each of Blazer Brass, Speer Lawman, and Speer Gold Dot. The websites say that the Lawman and Blazer Brass should get 830 ft/sec out of a 5" barrel. The Gold Dot is claimed to get 890 ft/sec from a 5" barrel. My barrel is 4.4".

For averages of 10 rounds each I got 816 ft/sec for the Gold Dot, 746 ft/sec for Lawman, and 776 ft/sec for the Blazer Brass.

I'm not sure how to go about varifying whether its the gun or the chronograph. I have other guns but I have never shot factory ammo through the chronograph with them, so I don't have a baseline. The chronograph is Competition Electronics ProChronoDLX. I think I'll send a message to them and see what they have to say.

In going back to DocSavage's comment, are the velocities I'm seeing in the ball park or do I have unrealistic expectations?

In the mean time, if anyone has other ideas, I'd like to hear them.

[DocSavage]

I use a 250 gr swc in my 625 over 5 gr Red Dot in Starline 45 AR brass haven't tried that weight in my 45 autos.