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captn-tin
06-10-2022, 04:28 PM
How do you determine a correct oal of a round when using a hard cast bullet by unknown maker. Friend gave me a bunch of 122gr, .356 flat nose bevel base hard cast bullets I'd like to load for my 1911 38super. Bullet has 1 grease groove and is lubed with a purple colored lube. I found loading info for round nose 122 gr.ers, but these I have are of a different configuration than the round nose. Thanks for any info....Captn-tin

poppy42
06-10-2022, 05:03 PM
Well I can tell you what I’d do. Others approach may be different. First thing you have to understand is that overall length is a guide and in many cases It has to be adjusted to fit the individual firearm. Generally what I do is find a lead bullet with a similar profile and use that as a starting guide. Load a couple rounds, make sure they pass the plunk test, make sure they feed and chamber in your gun and go from there. Oops just saw the part of your post about round nose boolets. Do you have a Lyman cast boolet handbook? It lists a rcbs 124 grn Cn and a Lyman 120 grn flat nose boolet. They have an oal of 1.250 and 1.230. Are the round nose boolet the same Length as the new boolets you received? Like I said listed oal is ment as a guide and not an absolute! Hope this helps

Winger Ed.
06-10-2022, 05:07 PM
Try the OAL for similar shaped boolits listed in a loading book.
Or start with a low-ish charge, and taper crimp just above the grease groove.
If they fit the magazine and chamber up-- go from there working up a powder charge.

You'll probably end up with a short OAL like the light SWCs made for a .45ACP that are shorter than a 230 hardball.

Der Gebirgsjager
06-10-2022, 05:59 PM
My method is to take the recoil spring out of the pistol so the slide will travel back and forth with little effort. Insert a boolit into a fired case, place it into the chamber, and slide the slide forward gently, allowing the chamber shoulder to push the boolit back into the case. Carefully open and remove the case and boolit. Next, ascertain if that length will function through the magazine. Then crimp at .002 shorter. Don't forget to put the spring back in!

DG

Mk42gunner
06-10-2022, 06:24 PM
Step 1. Make it fit the chamber. After it passes the plunk test-

Step 2. Make it fit the magazine. If it doesn't after step 1.

Step 3. Make it feed. Check by hand cycling dummies.

Step 4. Develop your load. It does no good to load a bunch if they won't cycle in your gun.

Robert

justindad
06-10-2022, 06:38 PM
If it has a step where the round profile begins and the driving band ends - I like to keep that step at least 0.050” in front of the case mouth, if possible.
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Watch the case volume. Measure the length of your bullet and compare it to the length of bullet from which you get your load data. Ideally, the case volumes will match.
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Download a free copy of Gordon’s Reloading Tool to further understand the relationship case volume has on pressures. That software also has bullet lengths of many cast bullets.

poppy42
06-11-2022, 04:51 PM
My method is to take the recoil spring out of the pistol so the slide will travel back and forth with little effort. Insert a boolit into a fired case, place it into the chamber, and slide the slide forward gently, allowing the chamber shoulder to push the boolit back into the case. Carefully open and remove the case and boolit. Next, ascertain if that length will function through the magazine. Then crimp at .002 shorter. Don't forget to put the spring back in!

DG

Never done it with a handgun but that’s about the way I go about it for a rifle. Load a dummy round loose and long, carefully close the bolt, allowing it to push the projectile back. Carefully remove measure it make it a few thousand shorter