.40 min oal

[MrJones]

I don't know if this question has been asked/answered but I can't do a search with terms less than 4 characters.

I was checking reloads from Miwall and have a average OAL of 1.130 (180 gr jacketed). I don't know what the min OAL should be but made 1.120 my cutoff. Is this reasonable?

I do not reload and have just begun to look into it. I don't know what kind of powder Miwall uses and a table I've looked at has min OALs ranging from 1.085 to 1.135 by powder. All advice is greatly appreciated.

Thank you for your time and response.

 

[Sub MOA]

Mr. Jones,

Your concern is valid, especially since you're talking 180gr. bullets. Seated deeply, these heavy bullets eat up case capacity and small differences in seating depth can run up pressures quickly in the already high pressure .40.

Your OAL figures jive with mine. I've got several reloading manuals and 1.125" is a fairly common min OAL. I load moderate level loads to 1.125" and have never had any problems, though if I were to load to full power I'd probably seat them a few thou longer for peace of mind. I wouldn't think factory rounds at 1.120" should be a problem.

HTH,
Sub

 

[Chemistry]

I never go below 1.125" when loading .40's.

Almost all of my .40 recipes use Alliant Power Pistol, and my 165 and 170 grain recipes use a 1.130" COAL. 180 grainers, I use 1.135", as long as they reliably feed in my Glocks.

These are conservative COAL's, and I do this just to ease my mind when it comes to pressure concerns. Surprisingly, it doesn't affect my velocities that much when I use Alliant Power Pistol. I suspect I'd have a bigger difference if I were brave enough to use a fast-burning propellant powder (which I won't with this cartridge).

 

[ryucasta]

Most of the reloading manuals post 1.126 as the OAL length they recommend for their loads. I currently hand load my Major PF loads at 1.160 due to the finicky nature of 1911 double stack magazines. I.e. Para, SV and STI