Sport pistol minimum OAL

[Crazy Horse]

Good morning,

Went to the Alliant reloading site for a recipe on 9mm 125gr LRN using sport pistol. The site states min OAL for their tested load is 1.12. The max charge is 4.2 grains (I reduced that by 10%-3.8 grains as a starting load).

Has anyone used an OAL of 1.090 or lower?

I have noticed that the ogive for cast bullets is wider than comparable plated and jacketed bullet load data. Because of the wider ogive on cast bullets (ACME and to an even greater extent Brazos Precision), using an OAL of 1.090 ensures my reloads pass the plunk test. At 1.10-1.17 the bullet sits right on the barrel. This means that it should work. However, I'm my experience, using OAL's greater than 1.090 (on my m&P Compact and taurus G3) will result in the bullet getting in the chamber fine, but sometimes, when I have to clear the firearm (ie completed a stage in a match), I cannot clear the chamber when directed by the safety officer (bullets gets stuck in the chamber and I have to push on the slide against something firm). I have already polished the chamber where the bullets sits, and it works well with reloads at 1.090, but gets iffy when I use OAL's (with cast bullets only) greater than 1.090.

When Using jacketed and plated bullets, I've gone up to 1.130 with no issues whatsoever. It's just cast and coated bullets that cause this issue (greater ogive).

Lastly, I know that SAAMI states that 1.000 is the minimum safe OAL for the 9mm, but thought it best ask if anyone has gone below what Alliant has published on their site.

TIA

CH

 

[fxvr5]

There's a lot of misunderstanding about OAL. You can use any OAL you want. This includes longer and shorter than what SAAMI shows. All that matters is that, 1) it fits in the magazine (cylinder if a revolver), 2) it fits in the chamber, 3) it feeds reliably (irrelevant if a revolver).

Loaded OAL lengths that are different than published data need adjustments in powder charge weight to keep the pressure the same. SAAMI's minimum length is not a minimum 'safe' length, it's just their minimum recommended length. You can load shorter than that if necessary, but really short semi-auto rounds have feeding problems.

 

[Charlie98]

I'm pretty careful with 9mm OAL because of pressure issues I've had in the past... having said that, with a 10% reduction like you are doing, I wouldn't have a problem with a deeper seat. I would say if you are aiming for a middle of the road load you will be OK, but if you are looking for max velocity, just be careful as you near max charge.

SportPistol has position issues, in your favor I think the deeper you seat the bullet (within reason, of course) and the nearer you get to max charge (fuller case) the better it will perform.

 

[BC17A]

I cast the Lee 125gn round nose and have loaded them as short as 1.055" for a few different pistols. My best load with that bullet is 4gn SP which is just into the +P range. The data I have for Sport Pistol shows an Acme 124lrn at 1.050" oal with 3.9gn for a max charge.

 

[Crazy Horse]

I cast the Lee 125gn round nose and have loaded them as short as 1.055" for a few different pistols. My best load with that bullet is 4gn SP which is just into the +P range. The data I have for Sport Pistol shows an Acme 124lrn at 1.050" oal with 3.9gn for a max charge.

Thx. That's what I was looking for. I know you can go to different seat depths, but I was inquiring to see if anyone had already conducted testing. The Max charge from alliant for 125gr LRN lists it at 4.2. I was looking at putting together some at 4.0 grains to see how they perform and feel. At 1.090 4 grains looks totally doable. I'll do some test loads using 1.090 with 3.8 grains of SP and another load with 4.0 grains of SP at 1.090.

CH.

 

[Dudedog]

9mm reg pressure

9mm +P



edit: From Alliant Sport Pistol loads (I should say where it is from)
Here is page 1 of it.

 

[Crazy Horse]

9mm reg pressure
View attachment 949945
9mm +P
View attachment 949946

THX Dudedog.

You mind me asking where you got that info from. I looked in all of my literature and on Alliant's website. Didn't see anything with that low of a COAL. The Lyman Cast Book which is one of my goto books and usually lists OAL's in the range that work well for me doesn't have Sport Pistol Data.

It's getting to the point that unless I've already used a tried and tested cast bullet in my firearms and works well in all of them, I'm hesitant to try new products. Still have ~200 of Brazos precision that have way too fat an OGIVE. Cause me lots of issues until someone on this forum indicated that the OGIVE was fatter than normal They work on a few of my pistols, but not the one's I use more often.

Much appreciated.

CH

 

[fxvr5]

data is from Alliant's website

standard 9mm pressure:
http://alliantpowder.com/reloaders/...wderlist.aspx&type=1&powderid=42&cartridge=23

+P:
http://alliantpowder.com/reloaders/powderlist.aspx?type=1&powderid=42&cartridge=189

 

[lordpaxman]

Went to the Alliant reloading site for a recipe on 9mm 125gr LRN using sport pistol. The site states min OAL for their tested load is 1.12. The max charge is 4.2 grains (I reduced that by 10%-3.8 grains as a starting load).

The Alliant site has data for a 124gr Acme coated bullet. I will use 124 data for a 125 gr bullet provided it’s similar in nature. This is what I started with for a Bayou bullet but I only loaded starting at 1.110 and went up. Good luck!

 

[Crazy Horse]

data is from Alliant's website

standard 9mm pressure:
http://alliantpowder.com/reloaders/...wderlist.aspx&type=1&powderid=42&cartridge=23

+P:
http://alliantpowder.com/reloaders/powderlist.aspx?type=1&powderid=42&cartridge=189

Ah, he clicked on the product Sport Pistol that lists everything and isn't manufacturer specific. Took me a minute.

I was going to the specific bullet in a different page and not getting the list (as LordPaxman stated above). Took a minute.

Thought maybe it was from a different resource.

THX

CH

 

[Crazy Horse]

All,
Went to the range today. tested out the following OALs using Sport Pistol. 3.8gr@ an OAL of 1.15 - shot well, light recoil, good accuracy (no jams, but close). 3.8gr@an OAL of 1.090 - shot well, light recoil; and 4.0gr@an OAL of 1.090, recoil was a tad higher.

I think BC17A has it down. 3.9gr of Sport Pistol, but I am going to go with 1.090. That should get the recoil just right while maintaining accuracy.

Thanks everyone, for the help and recommendations.

CH