Nead a OAL for 9mm 125 gr LRN??

Rule3 · #1 12-01-2009, 07:38 PM

Out of three manuals and searching the web I can not come up with a consistent oal for 9mm 125 LRN bullet (Missouri brand). The numbers are all over the place from 1.10 to max 1.169. I am using HP38/W231 at around 4.0 -4.2 grs.

I seem to remember 1.125 as a common oal. With all the variances in bullets it's hard to get a consistent length.

Anyone loading this bullet and what length are you using??

OKFC05 · #2 12-01-2009, 07:50 PM

I shoot 4 gr of HP38 under the Lee 124gr bullet and just left the seater plug where it was for the 124gr PD FMJ, which comes out to about 1.14".
The good news is that with such a mild charge, the OAL does not make a rats except for gun functioning. The gun will tell you if you got it wrong.

Rule3 · #3 12-01-2009, 07:57 PM

OK, My main concern was seating to deep. I am pretty sure I loaded these at 1.125 in the past and they were fine. I seem to have misplaced my data. (OK I lost it)

I do however have the data you gave me for the 9mm 115gr RN FMJ

RidgwayCO · #4 12-01-2009, 08:11 PM

I load the Dardas 125gr LRN bullets to 1.140" COL, which gives me .215" of bullet being gripped by the resized brass case. They function 100% through all my 9mm handguns (S&W revos and Beretta semis). However, I've heard that CZ's need a shorter COL.

Rule3 · #5 12-01-2009, 08:17 PM

Thanks, I guess I am in the ballpark depending on what gun I am shooting. It would be nice to have a standardized length that will feed in all of them.I sure do not want to adjust my ammo depending on what gun I plan to shoot

RidgwayCO · #6 12-02-2009, 02:14 AM

OCD1, just work out which of your 9mm's needs the shortest COL (use a dummy round and your actual barrels), and then load everything to that length or a little less. As long as they feed and function in all your 9mm's, you're golden!

Rule3 · #7 12-02-2009, 10:05 AM

Quote:

Originally Posted by RidgwayCO

OCD1, just work out which of your 9mm's needs the shortest COL (use a dummy round and your actual barrels), and then load everything to that length or a little less. As long as they feed and function in all your 9mm's, you're golden!

I am not quite sure about what to check for? I have taken barrels and just dropped a round into it (other calibers as well) Will the round stick out a fraction due to head space? or are you saying, run dummy rounds through the mag and chamber in the gun (dry cycling) ?

deanodog · #8 12-02-2009, 11:14 AM

I loaded that same bullet and seated to the same col as a factory 115 gr FMJ and they would not feed in my sigma. They would run in the other 9mms I have. I had to go shorter col to run in the sigma. They would contact the lands and not let the gun go into battery. They were a PIA to get out when jammed in barrel. I don't have access to a caliper at the present. Your guns may be different. I would be sure before loading a bunch of them (I didn't).

OKFC05 · #9 12-02-2009, 01:45 PM

Quote:

Originally Posted by OCD1

I am not quite sure about what to check for? I have taken barrels and just dropped a round into it (other calibers as well) Will the round stick out a fraction due to head space? ?

Essentially, yes.
The OAL is not the critical measurement, it is whether the bullet is fat enough up front to contact the rifling. A long skinny bullet can have a long OAL and be OK, wheareas a bullet with a fat ogive may needed to be seated shorter to keep off the rifling.

That's one of the reason I keep saying that OAL is not an absolute, it just happens to be easy to measure. Meauring the rifling clearance at the ogive takes a special tool, or you can just drop it in the barrel and see if it sticks. The cartridge should freely fall in, and freely fall out when inverted.

Rule3 · #10 12-02-2009, 03:51 PM

Quote:

Originally Posted by OKFC05

Essentially, yes.
The OAL is not the critical measurement, it is whether the bullet is fat enough up front to contact the rifling. A long skinny bullet can have a long OAL and be OK, wheareas a bullet with a fat ogive may needed to be seated shorter to keep off the rifling.

That's one of the reason I keep saying that OAL is not an absolute, it just happens to be easy to measure. Meauring the rifling clearance at the ogive takes a special tool, or you can just drop it in the barrel and see if it sticks. The cartridge should freely fall in, and freely fall out when inverted.

OK, got it. I should be fine then I dropped it in my Sig barrel and it was fine. I also dry cycled 5-6 rounds through it (outside).

Thanks