Thread: Crimping ?
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Old 09-30-2012, 09:48   #76
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Originally Posted by PCJim View Post
GP, reread what Fred posted that I highlighted in red. The industry "max" length is 1.169, and some magazine/pistol combinations will allow for an even longer COL. The minimum is just that, with the published load. You can always go longer as long as the COL will work in your barrel/magazine.

The best guideline is to first disassemble your pistol and use the barrel as a guide. Load your rounds to the longest COL that will pass the drop/plunk test for your barrel. Your round should drop into the chamber without any protrusion outside the rear of the chamber. (You can take a factory round, drop it in and look at how the case head seats into the rear of the chamber.)

Second, test that COL in your pistol's magazine. Load a round into the mag. The bullet should not scrape the inside of the magazine. If your COL passes both tests, you're at a good COL for that pistol/barrel combination.

The reason we always recommend you load to the longest COL is that doing so provides the most available volume inside the case where the pressure is developed during firing. Always remember that for any specific cartridge, less case volume equates to more pressure. Since your components and pistol combination will almost never be the same as the testing apparatus used to develop the published data, it is always best to allow yourself some leeway. Stretching the COL is effectively providing some relief for the pressure.

Once you've become satisfied with the round and are overly familiar with pressure signs, you can work on slowly reducing the COL, should you find a strong reason for doing so.

Personally, all my FMJ and LCN rounds are loaded to 1.14 - 1.15. That COL works in every 9mm that I own.
I think you are saying that I should always for the max OAL? Is that basically it?
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