Scratching my head

[PaulB47]

I loaded up 12 cartridges of .327 Fed Mag using Fed .327 cases, Hornady 100gr XTP, Fed 205M primers, and 5.0gr of Titegroup (max is 5.2gr according to Hodgdon). I went out to chrono the loads.

First shot, I got a reading just over 1400fps. This didn't seem right but I figured I was just too close to the chrono (I've seen weird results from being too close before). I backed up to my usual 12' and took 2 more shots, 1233fps and 1234fps. Then I opened the cylinder to look. The first case was a bit hard to get out.

The primer on that first case was quite flat, and the case was obviously expanded to max just above the case web. The other cases looked fine, and dropped back into the cylinder easily, but the first case will not go in without pushing hard. So, I'm now thinking it really was 1400fps.

I've used Titegroup many times before but never have seen such pressure excursions. All I can figure out is my scale is sticky and I got more than 5.0 grains in that case. But when I weigh, I always get the pan swinging a bit just so the pivot won't stick so that seems unlikely too. I know about powder position sensitivity but usually Titegroup is very insensitive to that.

The primer is the only thing different from Hodgdon's recipe. I have had no luck getting my hands on Federal 200 primers. The 205M should be a reasonable substitute I would think. Anyway the other two shots were fine.

One other thing, there was actually a day between my first shot and the other two, not that that should mean anything.

Any ideas?

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[Tilos]

When I'm throwing small amounts of powder (like 5.0 grains of anything) I'll throw 10 into a larger case, and set the scale for 10x (would be 50 grains here).

Once weighed I'll adjust the measure and throw/weigh 10 throws again, and repeat as needed.
This way I'm adjusting the measure for an average, not the variation from throw to throw.
A bonus with this method is when you start throwing powder into cases, you have already thrown 10 loads after the final measure adjustment.

If you are using a bushing type measure disregard what I just typed right there.
Oh, and check that you are using the small spindle in you powder measure, if so equipped.
And I have to ask, is 3 rounds all that you have shot across crony of this load?

 

[ageingstudent]

No huge temperature difference on the different days? Sometimes that will make a load perform different. Not sure about 200fps and a flat primer though.

 

[Certaindeaf]

Weigh that case? interesting

 

[PaulB47]

I'm not using a powder measure, just an RCBS 1010 scale. Temperatures on the two days were similar.

I haven't shot more because I tend to stop when I have bad things happen.

I guess I will investigate the powder position thing. I haven't seen large excursions with this powder before, but I have with other powders. Maybe Titegroup works differently in this cartridge.

 

[rick benjamin]

I put my charged cases into a loading tray under a bright light.
Any charge of powder that looks different than the rest is a do-over.

 

[PaulB47]

It definitely is powder position sensitivity.

I put 4 in the cylinder and shot two with the powder forward, and two with it back. No chonograph because I was in the woods, but the first two cases fell out of the cylinder and the second two took a hard push. Also their primers were much flatter.

I wonder if my using small rifle primers has a hand in this.

I guess I will go back to H110 or 296 even though it is unpleasant to shoot because of the blast. Maybe just a starting load and leave it at that. I wish someone would publish a Blue Dot load, that is my only intermediate pistol powder.

I might need to re-check my .44 Mag Titegroup loads now, just to be sure.

 

[ageingstudent]

If you had some data for HP-38 for that caliber it might fill the case a little more at least. As small as Tightgroup charges are I've never heard anybody complain much about position sensitivity. Some guys swear by it. I like it for smaller cases. Sportsman's out in clackamas had a ton of powders finally when I went last weekend maybe Hillsboro store has something more mid range for you to try.

I wouldn't think it was the small rifle primers. Was the recoil noticeably different?

 

[PaulB47]

I've never heard anybody complain much about position sensitivity.

Me either, but it's true here.

I found a modern burn rate table:
Powder Burn Rate Comparison Chart @ www.reloadersnest.com (http://www.reloadersnest.com/burnrates.asp)

Lil'Gun is a bit faster burning than H110 at least, and I have some. A starting load fills the case to the bullet base so I will use that for defense loads. It's definitely out of the "pleasant to shoot" category though. The velocity variation is large too, but it averages about 1300fps so it will do the job. Now I just need to find a nice plinking load.

 

[Member 34319]

Iv'e had some weird 1st shot readings on my chrono before. If it is too weird I usually discount it and move on to the remainders average.

Honestly though, it sounds like your distance may have changed the reading. Exiting gases will trigger some chronos and cause it to read incorrectly. Make sure to read your chronographs recommended distance.

As for the primers doing what they are doing. Using rifle primers, virtually a magnum small pistol primer, would ignite the very fast burning Titegroup, too quickly, probably causing an overpressure, not too mention the fact that the chemistry and amount of propellant in the primer itself is added to the mix. Which again would cause a higher pressure.

 

[PaulB47]

Well, most people using light loads of fast burning pistol powder, particularly in rifle cartridges, use magnum primers. It's pretty standard practice.

Also this is a 45,000 PSI cartridge, much higher than the .357 Magnum, so rifle primers are the norm, at least for heavy loads. I read somewhere that all the CCI factory loads use a rifle primer. Rifle primers are also used in for example, the .454 Casull.

 

[Member 34319]

Well, most people using light loads of fast burning pistol powder, particularly in rifle cartridges, use magnum primers. It's pretty standard practice.

Also this is a 45,000 PSI cartridge, much higher than the .357 Magnum, so rifle primers are the norm, at least for heavy loads. I read somewhere that all the CCI factory loads use a rifle primer. Rifle primers are also used in for example, the .454 Casull.

I'm not too familiar with that. I've only used magnum primers on occasion when I couldn't find regular, and downloaded 10% as a caution. Never used close to max with magnums. I've also never used rifles in a pistol cartridge.

However if you were using a published load, but changed the primer to a rifle vs regular pistol, you could effectively change the pressure that load will produce.

 

[noylj]

Umm, have you heard of starting at the start load and, if no start load is listed, reducing the max load by 10-12%?
It's been the rule for about 100 years.
Check several manuals, and you'll see different max loads. This shows that differences in components can make a difference and your components don't match those used in any manual (yes, different lots of powder can be different and shift a max load--particularly with a fast and tempermental powder like TG--several tenths of a grain up or down).
Reloading requires care and a willingness to follow the safety rules.

 

[PaulB47]

I did work it up. I didn't just start with a max load - in fact I never got to the max load. It's only when I went "powder back" that it gave me high pressures, something I've never seen Titegroup do before.

Just got a response back from my query to Hodgdon. It's very lawyerly and I can't print it here because it is "privileged communications" but he whacked me for using a small rifle primer. So, what if I am using the CCI small pistol magnum, which is the same as their small rifle? And what about all the other sources that mention small rifle primers for max loads?

I wish I could find a box of Federal 200s somewhere around Portland. Then I'd try the same exercise with that (which would be the exact Hodgdon-published components) and see if Titegroup is still powder position sensitive.

I think I will just stick with my starting load of Lil'Gun, and avoid all these problems.

 

[Member 34319]

I would try another brand small pistol primer first before a magnum.

Also, as for powder shift and case positioning goes, I call BS. I've been using titegroup for almost a decade and never had any issues with it in those regards.

 

[Steve M]

Some info from here - Primer Info & Chart + Milspec Primers for Semi-Autos & Other Primer Applications (http://www.sksboards.com/smf/?topic=56422.0)

Pearce: "...the .327 Federal Magnum is loaded to around 45,000 psi, some 10,000 psi greater than the .357 Magnum... In this application, at least with full-power loads, a primer designed to withstand that much pressure without deformation should be selected. A good example is the Federal 200, the same primer that the factory uses."

Seems like trying with the Federal 200 might be worth it before dismissing Titegroup for this application.

 

[PaulB47]

Also, as for powder shift and case positioning goes, I call BS. I've been using titegroup for almost a decade and never had any issues with it in those regards.

Did you happen to try it with .327 Fed Mag? I'm just as surprised as you are; Titegroup has never given me a problem with that before, but I've actually done the test. Have you?

Find me some Federal 200s and I will be thrilled to give it a try, guys. I'm not going to buy a whole brick of the things and deal with Hazmat too though.

 

[gunsmith007]

I did work it up. I didn't just start with a max load - in fact I never got to the max load. It's only when I went "powder back" that it gave me high pressures, something I've never seen Titegroup do before.

Just got a response back from my query to Hodgdon. It's very lawyerly and I can't print it here because it is "privileged communications" but he whacked me for using a small rifle primer. So, what if I am using the CCI small pistol magnum, which is the same as their small rifle? And what about all the other sources that mention small rifle primers for max loads?

I wish I could find a box of Federal 200s somewhere around Portland. Then I'd try the same exercise with that (which would be the exact Hodgdon-published components) and see if Titegroup is still powder position sensitive.

I think I will just stick with my starting load of Lil'Gun, and avoid all these problems.

Long cases have problems with light load as bad as hot loads at max changing primers from small standard to small magnum or rifle changes the mix and can cause problems if you use magnums always download by 1 gr. To start most of the time this will solve any problems you will have

 

[mjbskwim]

Just make sure the gun is unloaded before this

 

[DeanfromOregon]

That's like a reverse squib.