Some of you may have seen my thread in the pistol section about my new Springfield EMP. I bought it a couple of weeks ago, and initially had some problems with my standard target load: A Berry's 115gr Plated Round nose over 4.0gr of Titegroup. I was getting stovepipes and the slide was short-stroking...failing to extract altogether, or sometimes extracting but not going back far enough to strip the next round out of the magazine. This was happening about 3 or 4 times per 10 round magazine. It was about 60 degrees out that day.

I increased my load to 4.3gr of TG with the same bullet (which is a max load for lead bullets...and I've always used lead data for my plated loads), and this seemed to resolve my problem. I had two more range sessions outdoors in about 60 degree weather, and another indoors, where I fired a total of about 450 rounds with zero problems.

Today I went out shooting with my wife, and using the same load from the SAME BATCH that I shot indoors earlier this week, I could not get the gun to run at all. I put three mags through it, and EVERY SINGLE round failed to cycle far enough to extract. I had to cycle the slide manually after every round.

I did have some factory Sig 124gr VCrown ammo with me that I put through it and it ran 100% with that. I ran the reloads through my Beretta 92FS and Glock 26 today as well, and they fed ok, although my wife did manage to get the Glock to stovepipe once, which is really abnormal.

The only difference I can think of is that it was about 30 degrees out today, with a stiff windchill down to about 20. Could titegroup really be that temperature sensitive as to run the gun just fine one day, and then have a 100% failure rate on another? I know the next step is to chrono them at different temps and see if there is a dramatic change...but it may be a while before I get a chance to do that.

I have never used it, but read quite a few warnings that it is sensitive to temperature on various fora.

Did you clean your gun? A lot of time a dirty gun in cold weather makes them tighter than normal. I don't use TG so your on your own.

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Originally posted by Blue68f100:
Did you clean your gun? A lot of time a dirty gun in cold weather makes them tighter than normal. I don't use TG so your on your own.

Yes, the gun is thoroughly cleaned and lubed after every range session. And like I noted above, it shot fine with factory ammo, so the problem is definitely with the reloads, not the gun.

I too have read that Tightgroup is temp sensitive.
I have used it occasionally in other calibers, but not 9mm.
I use Universal with 115 gr. Berry's plated at the USPSA matches in Wyoming (which temps can range from 30 to 90) and never had a problem.

PC

I've had good luck with Titegroup and the 115 grain plated bullet in the 9mm. I don't have my charge weight here, but as I recall it was just above 4 grains.

Of course pressure and cycling could be effected by COL too. Mine were mostly shot in warmer temps, 60+ at least. My more recent shooting was with the P938, and then a Ruger LC9.

I reference the lead & jacketed data, then often use my chronograph to see where I'm at.

THe shorter the slide the stiffer the recoil spring. I have sim issues with my xd45c trying to get lighter loads. It is pretty much a near full power loads. Try heavier bullets to generate more slide speed.

BTW, TG is not supposed to be temp sensitive, one reason it is popular.

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Originally posted by fredj338:
BTW, TG is not supposed to be temp sensitive, one reason it is popular.

Do you know where I can find documentation on this? I'm not disagreeing...I've just been finding information on forums that indicates either way, but no documentation to back it up. I am hoping to get the chronograph out this week, but may not be able to replicate the sub-zero conditions if the weather doesn't cooperate.

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Do you know where I can find documentation on this? I'm not disagreeing...I've just been finding information on forums that indicates either way, but no documentation to back it up. I am hoping to get the chronograph out this week, but may not be able to replicate the sub-zero conditions if the weather doesn't cooperate.

Just based on chrono results I have seen from my shooting buddies that use it. Now WST, it is inverse temp sensitive. Also proven by my chronograph.

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Originally posted by fredj338:

quote:

Do you know where I can find documentation on this? I'm not disagreeing...I've just been finding information on forums that indicates either way, but no documentation to back it up. I am hoping to get the chronograph out this week, but may not be able to replicate the sub-zero conditions if the weather doesn't cooperate.

Just based on chrono results I have seen from my shooting buddies that use it. Now WST, it is inverse temp sensitive. Also proven by my chronograph.

Now that IS interesting. I have some WST...I'll have to give it a try.

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I have never used it, but read quite a few warnings that it is sensitive to temperature on various fora.

But usually on the other end when it's hot and the pressure could spike. 4.3 gns. is listed as the max load in the Hodgdon DB for lead.

Starting to doubt the load.

How did the primer strikes look? Compared to the V-Crown primer? Looks flatter or more "rounded edges? I have noticed that my stock 9mm Sig barrel produced 50 fps slower results throughout most of the powder range used compared to a Bar-Sto barrel I had subsequently installed. Perhaps the 4.3gr of Titegroup is still on the edge of reliability. A chrono or careful inspection needs to be done.

Seating depth can also make a huge difference. Once I was loading a couple of hundred rounds in a session and about 175 in I noticed the seater die was loose- about a full turn. Longer seat (to a point) lower pressure, less energy to work the slide.

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Seating depth can also make a huge difference

A drop test of the seating depth should be made to determine the proper seating depth. But a load right at the upper edge of the powder manufacturer's recommended load should cycle the slide.

A finger dragging on the slide could cause malfunctions but by the description it sounds like the round isn't even opening the slide.

Pull a few bullets to check the powder load???

I have yet to see any scientific investigation on the topic. In fact, a few claim that it's reverse temperature sensitive and will burn hotter with higher velocities when cold. Either way, a load at the top of the chart is not going to vary enough based on temperature to be totally unreliable when colder. Something else is at work here besides the powder charge.

When I was using Berry's products, I found the jacket thin enough to make the lead load recipes useful. If you really wanted to, you could try a 4.5 gr. but not before eliminating the other factors.

Well, I went out with a buddy and shot the gun again today. I didn't have any more of the 115gr load, but I did have some 124gr over 4.0gr of TG, and it ran 100% with this load. It chrono'd at 976fps (an average taken from an 8 round string with a max deviation of 65fps, or about 7%). It was about 53 degrees out today...I have a hard time believing that ~25 degrees would make that much difference. I'm going to set some of these aside, though, and chrono them on a cold day and see if I get a significant change.

I also tried a new load today...a 124gr Berry's Plated RN over 6.5gr of HS6 (0.1gr under max). This load averaged 1170fps, and definitely cycled the gun with authority. I checked the primers and cases and didn't see any signs of pressure. I think I'll load up a batch of these, and if they continue to work well, may transition to this load for the EMP, as it obviously likes a little more oomph than my other guns.