Setting OAL For New Sig P210 A

[Jayhawker]

This is for a Zero 115 FMJ. Rather than using one of the OAL values in one of the many loading books I have, I went the route of doing the plunk test, seeing if the bullet could turn in the chamber, etc. Initially, it wasn't ejecting properly so I decreased OAL step by step until it seated properly, ejected and fit the mag all the way down. I ended-up with a OAL of 1.165". This, needless to say. is way longer than any reloading manual figure. I know that maximum OAL for 9mm is 1.169. Am I too near the max here? It appears to function correctly but am I running up against something I may not be aware of.

 

[bullseye308]

If it feeds from the magazine and cycles and ejects, and spins freely in the chamber, I’d run it. On the plus side you will have slightly lower pressure.

 

[bullseye308]

When I was loading 115’s I ran them all at 1.12 same as I do the 124 grain coated I’m loading now.

 

[higgite]

If it feeds from the magazine and cycles and ejects, and spins freely in the chamber, I’d run it. On the plus side you will have slightly lower pressure.

On the minus side, you'll get less velocity unless you use more powder. Depends on your priorities.

 

[LiveLife]

Zero 115 FMJ ... plunk test ... OAL of 1.165".

Am I too near the max here? It appears to function correctly but am I running up against something I may not be aware of.

115 gr FMJ has shorter bullet base and if loaded long like 1.165", can experience poor neck tension and result in bullet setback and/or lower chamber pressure build which can produce larger groups.

So even though 115/124 gr FMJ/RN bullets produce 1.169" Working OAL to feed reliably from the magazine, I USED TO load them shorter at 1.150". After conducting comparison tests between 1.150" and 1.130"-1.135" OAL, I found shorter OAL to produce smaller groups so now I load 115 gr FMJ/RN to 1.130" and 124 gr FMJ/RN to 1.135".

And if I want to squeeze out even greater accuracy, I will incrementally test shorter OAL down to 1.110" after conducting max case fill for powder charge (Working OAL - Bullet Length = Max Case Fill) and use shorter OAL if group size decreases.

And why not go shorter than 1.100"? Because 9mm is a tapered case, going shorter will actually start to decrease neck tension to where bullet will just drop into the case (And why there exists 9mm cases with step/ring at the base of case).

 

[Jayhawker]

115 gr FMJ has shorter bullet base and if loaded long like 1.165", can experience poor neck tension and result in bullet setback and/or lower chamber pressure build which can produce larger groups.

So even though 115/124 gr FMJ/RN bullets produce 1.169" Working OAL to feed reliably from the magazine, I USED TO load them shorter at 1.150". After conducting comparison tests between 1.150" and 1.130"-1.135" OAL, I found shorter OAL to produce smaller groups so now I load 115 gr FMJ/RN to 1.130" and 124 gr FMJ/RN to 1.135".

And if I want to squeeze out even greater accuracy, I will incrementally test shorter OAL down to 1.110" after conducting max case fill for powder charge (Working OAL - Bullet Length = Max Case Fill) and use shorter OAL if group size decreases.

And why not go shorter than 1.100"? Because 9mm is a tapered case, going shorter will actually start to decrease neck tension to where bullet will just drop into the case (And why there exists 9mm cases with step/ring at the base of case).

Thank you those that have replied. I have several 9 mms and never had to work too hard to find accurate loads. This Sig is another story. Most of the loads I've tried had COLs from a Lyman or Hornady manual including 1.060, 1.090 and 1.125 using Titegroup, Bullseye, Unique and Power Pistol. Most of the targets looked like I'd fired a shotgun at them. One that really stood out however, was not a reload but Winchester 115 JHP Silvertip. All 5 shot groups were about an inch at 25 yards off the bench. I was thinking there was something wrong with the gun or the red dot sights until I fired this ammo. Now I'm kicking my self for not measuring the OAL of these rounds. I'd also be curious about what powder Winchester used. I'll resume my testing when I get some new Starline brass this week. I'm aware of setback when setting too long of a COL. I started at 1.169 and went down to 1.165 before the dummy round did not set back. I think I'll pick one powder for now (probably Power Pistol) and work up to 1.160" starting at 1.125 once I can get some 115 JHP rounds. Any info as to what length increments people use when testing OAL?

 

[LiveLife]

Any info as to what length increments people use when testing OAL?

I use .005" increments but you want to start out long at Max/Working OAL then incrementally shorten to see if accuracy improves - https://www.thehighroad.org/index.p...-and-discussions.778197/page-10#post-11419509

 

[Blue68f100]

The Sig's I have prefer the 124gr bullet. The 115gr POA does not match POI.

 

[Jayhawker]

The Sig's I have prefer the 124gr bullet. The 115gr POA does not match POI.

Thank you for your reply. I have some 124 JHP. Would you mind giving me your powder load and COL? Maybe I can shortcut my way to a good load.

 

[bullseye308]

My most accurate loads are a 124(5?) gold dot over be86 at 1.12”. Pretty much any RMR 124/125 jacketed bullet and be86 works exceptionally well for me in 4 of my 9’s.

 

[Jayhawker]

My most accurate loads are a 124(5?) gold dot over be86 at 1.12”. Pretty much any RMR 124/125 jacketed bullet and be86 works exceptionally well for me in 4 of my 9’s.

Thank you.

 

[lordpaxman]

My American sigs allow generous COLs. The German ones not so much.
Be advised you can go longer than the published COL safely, but if you go shorter you’re outside the lines. You didn’t mention your intended uses but powders faster than BE86/PP can be employed for target loads with great success. Good luck.

 

[Jayhawker]

This Sig will be used primarily for 25 yard target shooting. No formal competition. I just compete with myself which is tough enough. At least for now, I will test 115 FMJ and 124 JHP using Power Pistol, Titegroup, Unique and Bullseye. This is the first pistol I've ever had to do extensive load testing for. With all my other pistols I've just taken a few guesses and had success. This thing is way too picky but as noted above, I shot some Winchester 115 Silvertip into a one inch hole at 25 yards off the bench so I know the gun is capable. Have you or others found that shooting 3 shot groups is adequate for testing or do you think using 5 shots is better.

 

[lordpaxman]

In the past, when components were plentiful, I loaded 10 shots for load development, shot 9 and saved 1 in case I needed to disassemble it. Let us know how it goes.

 

[Blue68f100]

For quick screening 3-5 shots are fine. But it will take a lot more to prove it's a consistent preforming load. I normally do 10 shots ( or mag capacity) when I'm doing hand guns. Then once I find something promising I load up a larger batch to test, which normally include a OAL test to see if shorter or longer improves the group.


USE a rest when testing handgun to eliminate as much as possiable shooter impact.

 

[Jayhawker]

I"m still in the midst of bench testing this Sig P210 American. Among the test targets (25 yards from a rest) I shot these two. They are both 124 grain JHPs. The first had 3.8 grains of Titegroup, the second had 4.1 grains. Both had a OAL of 1.150". They were shot one right after the another. Do the almost identical targets say anything of significance or is it just some weird-ism in my shooting? I get fliers in the course of shooting but these targets were almost identical.

 

[lordpaxman]

It’s difficult to draw a conclusion with n=5, but at 25 yds I pretty much chalk up flyers to me. Are you shooting right or left handed? Right would be tightening grip, left would be jerking.
OTOH, gotta love Titegroup’s performance.

 

[Jayhawker]

Thank you all for the replies. That being said, I'm through testing this Sig. I've spent enough time, valuable powder and primers that I'll take what I've got. I am satisfied that I've been through enough bullets, COLs and loads of different powders not to mention the purchase of a 1000 new Starlines, that I've covered enough of the gamut of possibilities. I think I victimized myself over the years into thinking that the P 210 was the ultimate and in the long run if you wanted a target 9mm without going to the custom built stage or buying the overseas model, that this was the way to go. And I still think it is an excellent pistol. The good groups, all shot from the bench through a red dot site at 25 yards, range from just over an inch to 2 inches if you throw out the occasional flyer which, I think, was from yours truly and not the gun. With that said, I have two nines one of which shoots better than the Sig-an STI 6" barrel and another, a CZ CTS, which can shoot as well as the Sig and both having better triggers than the Sig. (I have found that the Sig does have an excellent, smooth and light trigger but the pull is way too long and even from the bench may be the reason for not having a smaller group size or possibly fewer fliers.) The fit and machining are obviously excellent for a "store bought" pistol.

With apologies to this group, I will be posting this to another group that I participate in since I'm a lousy keyboarder.