OAL on .380's with a Ruger LCP

[45taurus]

Ok guys what OAL are you using for 380 with the Ruger LCP? I think i may still be underpressure with this load and am not wanting up the powder so i may need a shorter OAL. Right now i'm using...

95g MBC LRN bullet

3.1g of w231

.964 OAL


Now i seem to be getting powder residue on the outside of the casings suggesting i'm underpressure. also im using federal primers and they are not flattening out at all. (usually federal is soft enough that they flatten easily, if i'm not mistaken, even with moderate loads)

So what OAL are you using? Am i too long? powder range is 2.3-3.5g.

 

[rcmodel]

Don't try to adjust pressure with seating depth.
It is unrelable at best, and dangerous at worst.

In general, longer will feed more reliably then shorter.
And you will quickly reach a point where the RN bullet ogive/front driving band is smaller then the case mouth when seated too short.

You can probably safely go up to 3.5 grains W231 with a 95 grain lead bullet seated .980" AOL.
The MB RN may be a shorter bullet then the Lyman #356242, I don't know.

But I do know the correct seating depth with it is with the case mouth about a fingernail thickness below the front edge of the front driving band.

I'd increase the powder until the smoking goes away and ejection seems normal.
Just watch for any signs of guppy-belly cases where they start to bulge into the barrel feed ramp cut.
If you see it starting, back off the charge a little until it goes away.

rc

 

[45taurus]

I dont know if i can go much longer because .964 is pretty much flush with the barrel hood.

 

[mxl]

I've been loading 100 gr. plated with 3.2 to 3.4 gr. of 231 and OAL of .970 and running it in my Kel-Tec P3AT [Ruger LCP is a clone] and several other 380s with good functioning.

 

[rcmodel]

.964 is pretty much flush with the barrel hood.

What has the barrel hood got to do with it?
MAX OAL for any .380 round is .984".
MAX case length is .680".
Either will chamber fully in the LCP unless the bullet is seated out so far it is hitting the rifling.

Oh, you are saying the front driving band is hitting the rifling before it can fully chamber??

Again, seat so the front of the case mouth taper crimp is just a froghair short of the front edge of the front driving band.

It will not hit the rifling leade at whatever length that is.

rc

 

[ants]

I haven't been loading lead bullets. Just plated and fmj.

For Ruger LCP my cartridge overall length is 0.956 for 95 grain and 0.962 for 100 and 115 grain.

My tiny little experience: 380acp doesn't respond much at all to shorter OAL in an attempt to increase performance. There just isn't much powder in there to make a bigger boom. Surely, the shorter OAL does decrease available case volume. But the bullet moves almost immediately, so your effective combustion volume increases right away.

W231/HP38 is an excellent powder for 380acp. VV N320 is even better.

On the question of increasing powder charge: The powder charge is so small that my powder measures can throw 3.5 grains much more reliably than 3.1 grains. Much less variance from throw to throw. Give it a try. You may be very pleased.

 

[45taurus]

What has the barrel hood got to do with it?
MAX OAL for any .380 round is .984".
MAX case length is .680".
Either will chamber fully in the LCP unless the bullet is seated out so far it is hitting the rifling.

Oh, you are saying the front driving band is hitting the rifling before it can fully chamber??

Again, seat so the front of the case mouth taper crimp is just a froghair short of the front edge of the front driving band.

It will not hit the rifling leade at whatever length that is.

rc

Ok i will try it, i just do not usually go with a max load, but the moderate seems to be underpressure so i will give it a try.

I have an old reloading buddy tell me when i drop a bullet in the barrel to make sure the OAL isn't sticking out past the barrel hood. Thats where i got that from. Is that a bunch of crap or what?

 

[J_McLeod]

This weekend I loaded and shot 10 rounds of .380 with 2.7gr Win231 behind a 96gr Slash K LRN at .980 with a CCI 500 primer in my LCP. They all cycled well, and shot much softer than factory ammo.

 

[Seedtick]

I have an old reloading buddy tell me when i drop a bullet in the barrel to make sure the OAL isn't sticking out past the barrel hood...

Yes, that's kinda right. I not going to try to explain it when Walkalong and others can do it soooo much better than me.....

Hope this helps.

Seedtick

 

[45taurus]

so...should i not extend the OAL then? The bullets are really short and fat. not sure how much further out i can seat them out either...

when i get home later today i will post pics of what i'm making right now and we can go from there. Something just doesn't seem right....they shoot and function fine though.

 

[jacksgd]

I use a Missouri bullet 95 grn. lead round nose with 2.9 and 3.0 grains of W231. With a COL of .970 several hundred rounds have all worked flawlessly through my Ruger LCP.

 

[45taurus]

Today, 07:47 AM * #11
jacksgd
Member
*
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Join Date: January 13, 2011
Posts: 2
I use a Missouri bullet 95 grn. lead round nose with 2.9 and 3.0 grains of W231. With a COL of .970 several hundred rounds have all worked flawlessly through my Ruger LCP.
*
That would make my pressure even lower. Maybe I'm being to anal about it, but my 45 cases have no powder residue at all on them

 

[ranger335v]

"(usually federal is soft enough that they flatten easily, if i'm not mistaken, even with moderate loads)"

That's 'common wisdom' but I don't think it's true. Federal uses a more sensitive priming compound that is easier to ignite than others so some seem to have decisded that means it's "softer." I've found Fed primers to easily take any pressures other brands do and even better than some lots of others.

 

[ants]

Industry representatives confirm what Ranger said in the post above.

The entire industry appears to use the same brass sheet (it's brass, not copper) to punch out primer cups. None of them are 'softer' or harder.

If any manufacturer actually used a softer sheet, those primers would easily pierce and blow out using the same loads that every other primer survives. Then nobody would buy those weak and soft primers. So the entire industry uses essentially the same sheet brass to get similar performance under load.

Every manufacturer has its own proprietary priming compound (the impact-sensitive chemical that goes boom). Some are more sensitive than others, some have more 'brissance' than others, some contain powdered metals like aluminum to help ignite the column of gunpowder above the flash hole. The compound is what makes the difference. That's why some are easier to ignite than others. That's why some flatten primers sooner than others. It's the compound, and how the compound ignites the powder.



But the "Federal Is Softer" thing has been floating around so long that many reloaders will never let go of it.

Learn to interpret "softer" as referring to the compound, not the metal cup.

 

[ants]

Using barrel (and barrel hood) to double check OAL

That's an EXCELLENT idea for autoloading pistols.

All bullets have a different nose profile, as noted by one of the posters above. Some may hit the rifling sooner than others. So you select your cartridge OAL and make a dummy round to check. Pull the barrel and see if it drops all the way in, or hits the lands early and makes the case head stick out past the barrel hood. The cartridge should drop all the way and go Plunk when the case mouth headspaces on the stepped end of the chamber.

 

[ants]

45Taurus - my tiny little advice if you don't mind me talking...

Your OAL of 0.964" seems perfectly normal for that cartridge.
What cartridge OAL does your load manual list?
Nothing wrong with using the OAL listed, and you can always load longer.
If you load longer, always check to make sure it fits the chamber.
We pretty well covered that in this thread.



So, your big question is soot staining on the outside of a 380acp case.
Your 45acp cases don't show soot, so you believe that 380acp should be the same.
No, they are very different cartridges. The 380acp generally runs on EXTREMELY low pressure.
It also has very thin case walls.
Sometimes the pressure seals the case to the chamber.
Sometimes you get a little leakage.
No big deal.

The big question: How do they shoot?
Do they cycle well?
Do they hit the target accurately?
Are you pleased with performance?

If the answers are Yes, then you may adjust the powder up or down to your liking.
Just don't lose function and accuracy.
Thinking that you MUST adjust pressure upward to avoid stains on the outside of the case is not the only criterion.
Function, shootability, and accuracy are the first criteria.
Make sure you keep those, don't worry so much about the case.

Let me also mention, the thin walls of the 380acp case are more delicate than 45acp.
Too much pressure, they will split sooner.
If case life is important to you, find a nice softer load that shoots well.
Stains on the case are no big deal.


But there is nothing wrong with running your own experiments, within the load data in your book.
So I say, go ahead and experiment to see how it responds.
Go ahead and try different powder charges.
Go ahead and try different OAL combinations.
Experiment with it. See how it responds.

 

[45taurus]

wow thanks ants for taking the time for that reply.

Everything feeds and functions very well and accuracy is not bad at all. Probably better than what i can shoot with it right now. (its new and i'm still getting used to it, especially the long DA trigger). I'm very satisfied with the round, except that i'm getting powder residue on the outside of the case. If that really is not a big deal, then i will live with it and load a bunch of these up.

Thanks again.

 

[Clark]

The magazine that came with my LCP will feed .980 115 gr JHP.
The magazine that came with my P3AT will feed .974" 115 gr JHP
The barrel that came with my LCP makes the case bulge at .270"
The barrel that came with my P3AT makes the case bulge at .290"

So I load one kind of ammo for both, so I make it wimpy enough and short enough for the P3AT, so it will also work in the LCP.

 

[ants]

That's dang good info, my friend Clark.
That's the value of measuring and testing.

I don't have a P3AT. I have an LCP and Colt Pony.
I load for the LCP. The Colt can take anything.

My best self defense loads are VVN320 with 115g XTP.
Paying attention to your load manual,
you may consider exploring the N320 for top performance.

 

[ants]

Let me mention one more thing about my own tiny little 380acp experience

As a carry piece, I load and unload often.

To get the best bullet tension, I use a good RCBS sizing die.
I use bullets with very consistent diameter.
I bell just barely, just so the bullet can start its slide into the case.
Then I crimp just barely, just to close up the bell slightly.
The crimp does not close tightly against the bullet, but sets out very slightly,
without interfering with magazine or feed ramp while feeding and cycling in the pistol.

AND I seat deeper than the gun requires.
I can seat all the way out past 0.970" with my bullets
and the gun chambers it just fine.
But I prefer to seat about 0.956 to 0.962 depending upon bullet.
At that seating depth, given my case prep and sizing,
I find that the bullet stays put in my case.

Since loading and unloading can push a bullet back into the case,
getting good case mouth tension is important to me.
My choice of OAL is part of that strategy.