9mm Luger loading woes.

[pathdoc]

Early this week I went out and shot a bunch of 9mm I had loaded up. The recipe was one which had previously worked in my gun, so I was expecting good things. Imagine my horror when numerous rounds:

1) Stovepipe jammed. Numerous of these.
2) Failed to go fully into battery. Pulling the mag and recycling the slide fixed this. Three or four of these.
3) Occasionally failed even to cycle (impact on the target confirmed that the projectile had exited the muzzle).

To me, the evidence points to insufficient charge for cycling the gun (Smith & Wesson M&P). But in this case, why should it not work where previously it did? Charges were thrown from a Lee powder measure, with intermittent checks.

Load was 4.2gn of 700X behind 115gn Hornady FMJ, under CCI or Winchester small pistol primers and Federal cases.

I could push the charge up to 4.3 or 4.4, but I'm pushing up against all the listed maxima I can find. I'm starting to suspect that all the maximum listed loads for 700X are wrong, because they date from the 1980s or so when the powder may have had a different energy per unit weight, burn profile or both.

Logic suggests that I should go on increasing the charge until it reliably cycles the gun, on the grounds that an unreliable load cannot possibly be over pressure, but am I making a horrible mistake in assuming this?

Could the powder have gone bad? My notebooks listing this handload as reliable for the gun date back from 2016. The powder did not smell bad when I opened the tins.

Am I right about a possible unsuitability of the pressure rate/burn curve? I thought to use it because I had ordered it in bulk for shotshell and knew that pistol loads existed, but I am now wondering if the time has not come to give up on that idea.

I am considering the purchase of a revolver, which will at least not have the feed issues. At least I will have something to use the powder in!

 

[big al hunter]

700x and the powder measure is likely to be your problem. The flakes of powder bridge the opening of the measure causing a light charge. But not always. Either put every charge on a scale, or change powder. My preference is Titegroup, but many others work well in 9mm. Power Pistol would be my next to try.

 

[Aguila Blanca]

The current load data for 9mm on the Hodgdon web site only show two loads to a 115-grain bullet with 700X powder. One is for a lead round-nose bullet, the other is for a Gold Dor hollow point. The load for the hollow point maxes out at 4.2 grains, but we shouldn't compare FMJ against HP loads unless we know the seating depth.

http://www.hodgdonreloading.com/data/pistol

What was the source of your load data, did you use the actual bullet specified in the recipe?

 

[Jim Watson]

The recipe was one which had previously worked in my gun

So SOMETHING has changed.

700x and the powder measure is likely to be your problem. The flakes of powder bridge the opening of the measure causing a light charge. But not always.

Also my experience with 700X in pistol loads. My CH Autochamp and Dillon 550b would both give the occasional one grain load. I never had a zero powder stuck bullet "squib" but enough short loads to be very aggravating. I got usable metering by putting a vibrator (aquarium air pump) on the Dillon's powder measure. But I eventually gave up and went to standard pistol powders like W231 and Bullseye. If I run short during the next Political Panic, I guess I can get out that last can of 700X and the vibrator. I haven't loaded a shotgun shell in years.

 

[pathdoc]

Aguila Blanca, I was using generic 115gn Jacketed bullet data from Lee. Yeah, I know, Lee... but it's published data.

My use of 700X was driven by desperation and the inability to get my hands on literally anything else locally at the time (and with the shortages going on for who knows how long because hoarding/politics).

SO: the next (and last) test with 700X will be 30 rounds as follows:

1) 10 individually weighed charges (1 Canadian magazine full) of 700X.
2) 10 charges of 700X metered through the dispenser.
3) 10 charges of a minimum load of something - anything - else that I can find left over in my shed and have data for.

I determined by experiment yesterday that a randomly selected box of budget factory ammo functioned flawlessly. So it isn't the gun.

 

[Aguila Blanca]

Aguila Blanca, I was using generic 115gn Jacketed bullet data from Lee. Yeah, I know, Lee... but it's published data.

My use of 700X was driven by desperation and the inability to get my hands on literally anything else locally at the time (and with the shortages going on for who knows how long because hoarding/politics).

Yes, it's published data -- but you don't know what bullet, so you don't know the bullet length or the seating depth.

The Hodgdon web site has data for a 115-grain Speer Gold Dot bullet.Speer's web site says that bullet has a [bullet] length of .525 inches.

https://www.speer.com/bullets/handgun_bullets/gold_dot_personal_protection/19-3994.html

Going to the Hodgdon site, the maximum load for that bullet using 700-X is 4.2 grains, putting it right in the range where you are loading. The C.O.A.L. is listed as 1.125". We now have two pieces of dimensional data.

Looking at the SAAMI web site, the case length for 9mm Parabellum is .754-.010. I'll use the nominal, but you can measure your cases and be more precise. Now we have three pieces of dimensional data, and that's all we need.

If I take the listed C.O.A.L. for the recipe and subtract the nominal case length, that leaves 1.125-.754 = .371. That's how much bullet is exposed beyond the case mouth.

The bullet measures .525 inches. .525-.371 = .154. So their seating depth for that recipe is .154 inches.

You can run through this calculation for your bullet, using your average case length, and find your seating depth. That's the only way you can adapt load data to different bullets. The seating depth governs the volume remaining behind the bullet, and that's what controls pressure (and, thus, velocity).

 

[Machineguntony]

It could be any number of factors. You have to isolate and test for the changes.

I had this exact problem. It was driving me nuts because according to published data, I should not have had any problems.

I started identifying all the possible changes in my load and load procedure and realized that the first change was that I was now lubing my 9mm cases. That turned out to be the problem.

My issue was that I was mass lubing all the cases with my liquid lanolin + 99% alc. Previously, I had never lubed my 9mm cases, but a problem with tendinitis changed that. The lube got into the cases and was affecting the charge.

So I rolled 100 the cases on the side, so the lube didn’t get inside the case. Test fired those rounds. Problem solved.

Another cause of this may be that the powder dispenser is dirty and catching some of the charge.

Just isolate and test. That’s the only way you’ll figure out the problem.

 

[ghbucky]

Charges were thrown from a Lee powder measure, with intermittent checks.

Which Lee powder measure?

I've used the auto-disk, and had quite a few problems with it. I ended up rubber banding a .. ahem.. 'personal pleasure' device to it to keep the powder consistently moving.

I switched to the perfect powder measure and it works really well for me.

 

[Unclenick]

700X is a large flake powder. Large flakes are famous for causing the bridging problem. Additionally, QuickLOAD's author says he does not list powder models for 700X, 800X, or any of the SR powders from IMR because they keep changing suppliers and he found them too variable over time to trust a model he might put in the program. So change in powder since the data was compiled is another possibility, though Hodgdon claims to be keeping their data current.

Note that the Speer Gold Dots are bullets with plated jackets and not cup and core jackets. One of their technicians who has run the plating process told me they often are safe with higher charges than jacketed bullets are, so you want to take Gold Dot loads down to the start level and work up.

 

[Aguila Blanca]

Note that the Speer Gold Dots are bullets with plated jackets and not cup and core jackets. One of their technicians who has run the plating process told me they often are safe with higher charges than jacketed bullets are, so you want to take Gold Dot loads down to the start level and work up.

The OP has stated that he is loading a Hornady 115-grain projectile, but the current Hodgdon data (on their site) don't have any data for a 115-grain FMJ with 700-X. But they do have a 700-X load for the 115-grain Gold Dot. So I dragged the Gold Dot into the discussion to explain how to use seating depth to adapt the Gold Dot recipe to the 115-grain FMJ projectile.

 

[Unclenick]

I didn't make the reason I mentioned the Gold Dot clear: It is that the OP's load data is for 4.2 grains of 700X which is a match to Hodgon's Gold Dot maximum charge. It may be on the high side for the Hornady. It also may not, as this stuff varies with the gun and cartridge and bullet length, but it certainly shouldn't be too low to cycle the gun properly, again suggesting low charges were sneaking in or that his lot of 700X doesn't match the test lot burn rate well. I would tend toward suspecting the measure because of the large flakes first, as others have suggested.

 

[Grey_Lion]

I'd ask some storage questions - How is your powder stored? How are your primers stored? If you bulk-prime your brass - how are the primed shells stored? Once loaded - how was the ammo stored? Consider the possibility that either the powder or the primers went bad due to poor storage somewhere along the line so you aren't getting the ignition necessary to cycle the weapon. Are you noticing excessive smoke and/or GSR from these firings? Are you seeing excessive fouling of the weapon? Are you using a new batch of powder and or primers? - Could have a bad batch of either. If your materials and process haven't changed, then I'd be looking at changes in the loading environment. Did you just get a batch of pool chemicals in and stored them in the garage near the loading bench? That can do it.

 

[Aguila Blanca]

Getting back to the original question:

Logic suggests that I should go on increasing the charge until it reliably cycles the gun, on the grounds that an unreliable load cannot possibly be over pressure, but am I making a horrible mistake in assuming this?

Maybe not a "horrible" mistake, but IMHO certainly a mistake. Even a starting load should cycle a pistol with a factory recoil spring in it, so before you go flirting with +P territory I think it would be prudent to do a bit more in terms of sussing out where the problem lies. For example, do you have access to a chronograph? I would try running ten (or 20) of your reloads over a chronograph, looking not only for average velocity but more for extreme spread and standard deviation. If you're getting an unusually large extreme spread, that's a bit of evidence to support the powder bridging theory.

Next, I would try loading ten or twenty rounds exactly the same as before, except that I would weigh each charge manually to ensure that it's right on the money. Then see how those shoot, if they reliably cycle the same pistol, and (if you have access to a chronograph) what velocity they produce.