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.45 Acp Cartridge Overall Length


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#1 catnipman

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Posted 08 November 2005 - 12:04 PM

I was recently looking over the SAMMI .45 ACP pistol cartridge and chamber specifications, and noticed the large variation in allowable cartridge overall length (COL), namely 1.190 - 1.275 inches. I was wondering if anyone has an opinion about what, if any, is the optimal COL for the TSMG?
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#2 Bill in VA

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Posted 08 November 2005 - 12:37 PM

I load mine to 1.275" COAL. Either way though, you're looking at a difference of .085 and since the .45 acp headspaces on the case mouth, COAL in a TSMG shouldn't make much of a difference unless your feed ramp is out of spec.
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#3 PK.

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Posted 08 November 2005 - 01:45 PM

If the cartridges are short, you may have trouble with drums especially. I load my 230 RN 1.270 and all is well.

SWC styles will give you grief in drums also.

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#4 JimFromFL

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Posted 08 November 2005 - 02:07 PM

I have been using 1.260 with great success.

Disclaimer: Of course your length of cartridge should be determined by the manufacture of the powder and/or bullet manufacture being used.
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#5 catnipman

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Posted 08 November 2005 - 03:41 PM

Good advice. thanks much. I think I'll give the 1.270 a try. I've been loading a little bit shorter than that.
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