9mm...Seating deep to fit Sig P6. How short is too short?

[JW in Ohio]

I've enjoyed reloading 38 specials in the past, but have questions about my first attempt with 9mm with cast lead bullets. With 125gn bullets, I have to seat them very deep(1.024" length) to fit my Sig P6. The Lee manual calls for a min length of 1.095 using Win 231 powder. The Hodgdon website shows COL of 1.125".
Since 9mm headspaces on the case neck, it seems the bullet is engaging the rifling before the case neck bottoms out in the chamber. This cartridge loaded to full length fits fine in my S&W 639. Factory ammo fits fine in the Sig. It just doesn't like lead bullets...Is this because lead bullets are typically slightly oversized compared to FMJ, and the Sig has a tight chamber/short throat?
The lead bullets measure .356 compared to factory FMJ at .354.

Lee manual recommends 3.3 to 4.0 grains of 231 powder(124 grn lead bullet).
Hodgdon site recommends 3.9 to 4.4 grains of 231(125 grn lead bullet).

So after all this...will I be in trouble loading to 1.024 length with a 3.3-3.5 grains?

 

[Yarddog]

Not Really, It's a Good place to start, OMO Good Luck ; )
Y/D

 

[Quoheleth]

My CZ does the same thing and, FWIW, I crank mine all the way down to sub-1.07" OAL. I believe my charges of Win231 are in that 3.5 range --- I'm going from memory and am at work w/out access to my Lyman pistol manual. It's know it's a very light load and it might not cycle your gun. It basically flips the brass out of the chamber and lands almost at my feet.

It's the bullet profile that causes it to hang up. No worries. Shorten your OAL and get after it! That bullet shoots great.

Q

 

[F_L]

For my P6 I load 125 gr LRN to 1.07", 3.8 gr W231. I am having REALLY bad leading issues and will switch to plated or FMJ when i use up the lead.
Fred

 

[1SOW]

My Sig 239 is more forgiving than my CZ.

"Nose SHAPE" is a big determinate of rifling contact/seating depth. Three different brands/makers of "RN" may need three different oals.

 

[GIJOEL]

I loaded up a bunch of Missori bullet company's 125gr hardcast and had the same issue. I was using a similar load and just pushed the bullets back into the case to solve the problem. That said I have had bad leading problems with this load too, next time i'll up the charge (I'm loading on the low end) and see it that fixes the leading.

 

[JW in Ohio]

Thanks for the replies. It sounds like loading shorter than normal is not unusual...I'll give it a try if and when it ever warms up around here! It is a Missouri bullet I'm using and it is more rounded than the factory FMJ. A more tapered shape would solve the problem I'm sure. I'm not knocking Missouri...the bullets looks great and I'll continue with their stuff.

Interesting that both F L and GIJOEL both had leading. Upping the load may help since this is a Brinell 18 bullet and can take more pressure.

 

[RhinoDefense]

SAAMI OAL range for the 9mm is 1.00" to 1.70", so you have a lot of room to work with.

 

[918v]

I don't know why a P6 would have a different chamber than a P226 which has a huge chamber. Maybe P6's have P210 chambers where the lands slope down all the way down to the case mouth with almost no freebore?

Here's what I would do: Remove the barrel from the pistol. Take a fired case and flare the case mouth ever so slightly so the case will still chamber. Slip one of your bullets into the case mouth and chamber the dummy round by hand. Make sure the case head is flush with the end of the barrel hood. That's your max OAL. Seat the bullet .010" deeper and that's your working OAL.

I can tell you from experience that a 125gr lead TC meant for a .38/357 loaded to 1.050" will work with 3.7 to 4.1grs of 231, in a M9 anyway. Your LRN seated to any reasonable seating depth will have more case volume than that TC I was using. You will be safe starting at 3.7grains and working up.

 

[Jeff H]

SAAMI OAL range for the 9mm is 1.00" to 1.70", so you have a lot of room to work with.

I think you meant 1.170 not 1.70. The actual SAAMI max is 1.169, but I won't argue about 1/1000 of an inch.

 

[rcmodel]

The SIG P6 is chambered for German mil-spec FMJ-RN ammo.
As such, a blunter ogive RN, or a TC, or JHP will have to be seated deeper to miss the rifling leade.

Mine works with 124 grain Berry TC & HP at 1.060"
Berry 115 or 124 RN works at 1.147" although I have settled on 1.120" so they will work in my sons XD sub-compact too.

Mine will chamber any standard .355" or .356" 9mm bullet, but it chokes on .357" bullets.

rc

 

[RhinoDefense]

Yes, I meant 1.170. The "1" on my keyboard sticks sometimes. The official SAAMI drawing in my files shows 1.170, not 1.169.

 

[rfwobbly]

The Lee manual calls for a min length of 1.095 using Win 231 powder.

JW -
You are reading WAY too much into the recipe. These loads are tested in a bench-mounted "test barrel", not a handgun. As such they cannot recommend or "call for" anything. They can only report how their load performed.

What they are saying is, "If a cartridge built to this spec will fit and fire in your gun, then you'll be safe as long as your load between these 2 limits." And conversely, "If this cartridge will NOT fit in your gun, then all bets are off because we did not test it." They are in no way recommending a certain OAL as "magic" or the Holy Grail of shooting. Again, they are only reporting.

Thanks for the replies. It sounds like loading shorter than normal is not unusual.

Here again, you are reading far too much into the manual. There is NO "normal" cartridge length. The cartridge length is controlled by 1) how the bullet interfaces with the barrel, and 2) not to exceed the SAAMI maximum length. All bullets are slightly different shapes, and no 2 gun makers make their barrels using the same internal dimensions. Therefore there is no way Lee or anyone else can recommend an exact OAL for you. They can tell you what worked in the 1 or 2 guns they had with them at the time of testing, but that is far from a guarantee of it being a workable solution for you. And it is certainly not meant to convey any form or "standardization" upon that length.


Needing different OALs is why many reloaders build a library of numerous reloading manuals. If you have 6 manuals, then the chances of finding a load listed at something short like 1.040" is much better. And sometimes your barrel will simply demand you load a certain bullet that short. I would recommend the Hornady #6 as detailing some very short 9mm rounds.

Hope this helps!

 

[popper]

9mm crimp

I had problems with MBC 115gr. RN in a XD. The problem turned out to be the crimp, not OAL. 9mm is tapered, XD must use a tapered chamber. Worked fine in a glock, but wouldn't fit (full battery) in XD. 1.056 and 0.377 worked.