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Battis
05-17-2018, 09:45 AM
I have a Mauser 1914 .32acp. The bore measures .309".
I replaced all the springs and it shoots factory ammo just fine. I saved the brass and got some bullets from Montana Bullet Works (.311" 75 grs).
I loaded some dummy rounds. The published data I've found shows the OAL to be approx. .984". I cannot get the rounds to chamber until the OAL gets down around .925". Fired and sized or unsized cases drop right into the camber (barrel removed), so I know it's not the brass.
I'm kinda concerned about the pressure from having the bullet seated that deep. Could it be a problem? (1.5 grs Bullseye).
I just ordered a Lee bullet sizing die in .309".

Outpost75
05-17-2018, 10:24 AM
I'm not familiar with the Montana Bullet Works, but it sounds like its nose profile is incorrect for the .32 ACP.

The correct OAL for factory FMJRN is 0.980-.985"

The OAL needed for flatnosed cast bullets such as Accurate 31-077B, 31-084H, 31-087B, 31-087T and 31-090T to fit correctly in the magazine box, so that they cannot "shuffle in the stack" during recoil and cause "rim lock" is 0.945"-0.965"

Your 1.5 grains of Bullseye is not unsafe. It is a mild starting load and should be OK even with your increased seating depth.
BUT I would recommend a bullet having correct shank length and nose length of .26-.28" of suitable profile for the .32 ACP.

If your Mauser pistol does not need flatnosed bullets, Accurate 31-087B and 31-087T are the best choices, with 1.7-2.0 grains of Bullseye.

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Battis
05-17-2018, 12:27 PM
Good info. Thanks.
Usually I buy a gun, buy a mold (NOE or Accurate). This time I figured I'd just buy the bullets. Accurate lists #31-075R for 32 ACP. Looks like the way to go.

FergusonTO35
05-18-2018, 08:07 PM
I have the Accurate 31-076 and it's a great boolit. I load to .945 for my Kel-Tec.

Outpost75
05-19-2018, 10:39 AM
Another thing, not sure if you tweaked bullet diameter to fit your pistol, vs. ordering per the drawing in the online catalog. Normal tolerance on diameters is +0.002"/-0.000".

IF your pistol actually measures .309" on the chamber cast, you should either order the mold at .308" so that it either drops to correct size as-cast, in worst case requiring only minimal sizing to true up,

OR specify that the bore-riding nose "north" of the top groove as .309" - the same size as your chamber cast, but also specifying NOSE TOLERANCE NEGATIVE, to ensure that the bullet enters the chamber freely without resistance.

The ability to specify diameters and tolerance conventions as positive, negative or centered is unique to Accurate Molds.

Nobody else to my knowledge offers that option.