Determining OAL

[Mac_Menamy]

Good evening everyone,

 

so I am fairly new to the reloading game. Currently, I reload 9mm on a Dillon 550c. As I’ve done a lot of reading I’ve seen people have an OAL that’s a lot shorter than what any load data says (load data says OAL 1.169 and I see people loading 1.130 ~) is there a reason for this? I’m currently loading 147gr Blue Bullets and my current OAL is about 1.160. Is that ok? I haven’t had any real issues shooting out of my Glock 34 Gen 4 (USPSA Production). Any information would be greatly appreciated!

[RangerTrace]

You need to read my current thread about Hot rounds.  Lots of good info in that one....

[RangerTrace]

 

[Hi-Power Jack]

Welcome aboard, Mac.

 

Most people try to load as long as possible, ensuring that the rounds fit thru your

mags and feed thru your chamber.

 

If 1.16" is good, that's great, for 147 BB's.   If you change bullets, you might have                                                                                                                                                                                                  to change the OAL - all depends on each bullet, in your gun.

[superdude]

Mac_Menamy,  1.169" is the maximum overall length of the 9mm Luger round as defined by SAAMI.  http://saami.org/specifications_and_information/publications/download/Z299-3_ANSI-SAAMI_CFPandR.pdf#page=36

 

Almost everything you load will be shorter than 1.169". Actual OAL varies depending on which bullet your using. The loaded round has to fit in the magazine and chamber and feed reliably. To ensure it fits in the chamber, you have to do the plunk test.  Different barrels might require different OALs because of differences in how the chambers are cut.

 

Plunk test: http://www.shootingtimes.com/reloading/reloading-tips-the-plunk-test/

 

If you found a length that works for you, there's no need to change. 

[Mac_Menamy]

3 minutes ago, superdude said:

Mac_Menamy,  1.169" is the maximum overall length of the 9mm Luger round as defined by SAAMI.  http://saami.org/specifications_and_information/publications/download/Z299-3_ANSI-SAAMI_CFPandR.pdf#page=36

 

Almost everything you load will be shorter than 1.169". Actual OAL varies depending on which bullet your using. The loaded round has to fit in the magazine and chamber and feed reliably. To ensure it fits in the chamber, you have to do the plunk test.  Different barrels might require different OALs because of differences in how the chambers are cut.

 

Plunk test: http://www.shootingtimes.com/reloading/reloading-tips-the-plunk-test/

 

If you found a length that works for you, there's no need to change. 

Ok that makes sense! I knew not to go over the Max but just seeing 1.13” versus 1.15” I didn’t know if I was missing something

[Absocold]

SAAMI is just a system of standards and manufacturer published load data is just a safe starting point. Every gun is different and as long as you're using safe practices, move in very small increments and watch like a hawk for warning signs, what your gun ends up liking is what that gun likes. Don't sweat everyone else's details because they're all different and you'll make yourself crazy.

 

If you need help, advice or a place to start, we can point you in the right direction. But if you're happy with your setup then keep at it.

 

 

Side note: be very very careful on this particular message board regarding 9mm load info. A large number of the members here are loading 9mm ammo that's well outside the bounds of what would normally be called safe. The race guns that use this ammo (9 Major, 9mm major, etc.) are built to take that sort of abuse. But if you put these rounds in a normal gun you're probably going to have a really bad day.

[racer-x]

I see you are loading for a production Glock...

 

One of the side benefits of loading my 9 major PF loads long is that they won't easily fit into many production style magazines like your Glocks.

Accidental ingestion of one of my 174PF 9's in a Glock with a factory barrel would most likely be memorable. Action may not close completely with other short throated production guns. 

 

Also, you didn't mention anything about the 1911/2011 platform, but they like long loads in general since the original 1911 design dimensions were tailored  around the much longer 45ACP (1.275 max OAL). 

 

If the OAL of your loads is working reliably for you, then that's what matters. Welcome to BE. 

[Beef15]

Like others said, 1.169 is SAAMI max.

 

Slightly curious where you're finding your data as OAL is almost always on the shorter end in published data. Reason being in traditional pistol rounds going shorter raises pressure, going longer lowers it pretty much until you jam the lands, so typically the minimum OAL is a more important number than the maximum. Standard method for determining your OAL is the "plunk test" and then subtract some arbitrary amount 0.005-0.010" for reliability and confirming that length is more than the published OAL or starting low proceeding with caution if not.

 

IIRC small frame Glock mags limit you to about 1.165, I self imposed a limit of 1.15 with cast in my Glocks to avoid potential problems from the occasional minor inconsistencies they tend to exhibit.

 

ETA: Hi Power Jack caught it, meant shorten .005-.010

[Hi-Power Jack]

4 minutes ago, Beef15 said:

  1.  the minimum OAL is a more important number than the maximum.  

  2.  subtract some arbitrary amount 0.05-0.10" 

 

1.  I usually try to get closer to the max rather than the minimum

2.  I usually try to subtract more like 0.005"    e.g. if my max OAL is 1.135", I'd back it off to 1.130"

 

 

[Beef15]

 
1.  I usually try to get closer to the max rather than the minimum
2.  I usually try to subtract more like 0.005"    e.g. if my max OAL is 1.135", I'd back it off to 1.130"
 
 

Doh, decimal point off. Too early in the morning. There's many reasons to scrutinize all internet advice closely.

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