Low volume powders in large cases

[JohnhenrySTL]

I perhaps am phrasing this question wrong; I am wondering if a powder like bullsye or Winchester 231can discharge funny (or not discharge) if pointed low and the small volume of powder ends up gathered around the bullet and away from the primer in a large case such as a .38 special.

Ive shot more than my fair share down into ditches and never have experienced this.

Two of my reloading teachers have warned me of this.

I can imagine it but doubt it is an actual concern.

Has anyone experienced this, or a similar problem?

What are some reloading myths you guys have heard?

I am reminded often that you can go over modern books boundries pertaining to charges. I hear specs get tighter and tighter. In my experience I see pressure signs way before I get near max charge data.

 

[Walkalong]

Yes, if the powder is up against the bullet vs back against the primer it will generally lose some velocity. Some powders are better than others, and some powders, IMR4756 for example, aren't suited to light loads in .38 Spl cases at all because they are so position sensitive in that application. 4756 does much better when run hot, but it still likes to fill the case for best results.

That said, most fast powders in .38 Spl using published loads will only lose 100 to 300 FPS with the powder forward against the bullet, which won't get you in trouble unless you try to go too low. When starting at the low end always make sure the bullet exits the barrel. As you work up towards max, this is less and less of a problem.

I am reminded often that you can go over modern books boundries pertaining to charges.

Bad advise, especially for a new reloader.

 

[joem1945]

While I have not had a problem with low volume powders to date, I try to use powders that seem pretty much to fill the case. My reason is that you cannot double charge any case and I expect a more consistant burn rate.

 

[Steve51]

Recently experienced this very issue.
Always used Unique for my revolver loads (.32 H&R mag, .38spl/.357 mag, .44 spl/.44 mag). and never noticed any accuracy problems. Probably because I am not that good with a revolver.
Recently I was sighting in a scope on my .44 magnum lever gun. I could not get zeroed - shots were all over the place. Sometimes groups were in the 5inch range. I purchased some IMR 4227 powder and loaded a few rounds. This time I could easily zero the rifle. I assumed the low volume cases of Unique was the reason. When I ran out of IMR 4227, none was available so I purchased Alliant 2400. Again accuracy was very good (like IMR 4227). Both 2400 & IMR 4227 filled the cases near the bullet base.

I still like Unique - but not in .44 magnum loads.

Just sharing my experience and my thoughts. Might be right, might be wrong.

 

[ATLDave]

Lots of good answers already. I suspect you will now begin to notice that "not position-sensitive" is a selling point for certain powders. This issue is what they're talking about.

 

[Walkalong]

But don't always believe the advertising.

The least position powder I have ever tried was Solo 1250, and they discontinued it.

 

[xcalibor67]

Had a buddy who was asking a similar question. using fast burning powders in larger cases. Not that ive had any exp. with this, have been told that this "Could" cause problems. Was explained that a normal filled case with appropriate powder burns like a cigar, starts at primer end and burns forward.With the low volume charge, the powder can lay on the bottom half of the case and when ignited, it flash burns across the top of the powder, creating pressure spikes. Have always been told to use a filler with low volume charges..

 

[Walkalong]

I have never seen pistol powders "Spike" and give more velocity with when laying flat in a big case with extra room. It will lose some velocity compared to powder back, but will be better than powder forward, sometimes much better. Nothing drastic either way. I have never seen it give more velocity than powder back.

 

[Potatohead]

I am reminded often that you can go over modern books boundries pertaining to charges

May be true..but why would you really want to? Maybe Im a pansy but I get all the kicks and giggles I need by the the time Im halfway up the scale.

 

[JohnhenrySTL]

Potatohead I have no intentions of going over. I start noticing pressure signs within the specs of my load data. My point was people tell me they can go over, or that I have nothing to worry about. I find that false. Ill stick with with my data. I just recently loaded 44.5 grains of 4064 in a .308. The manual called for 43.x-47.x under a 150 grain. I got a little freaked out after looking at my brass after, ha. Using my current equipment, I sometimes am given the choice of tame or closer to published max charge than I like to make. Experienced reloaders have told me, I dont have to worry about it because of newer data is on the tame side.

I shouldnve asked 2 questions at once. I am confusing myaelf and others.

Thanks everybody. I guess its time for me to try out my chroneograph.

 

[gamestalker]

I experienced some very erratic velocities and general performance with 45 lc years ago that was the result of powder position sensitivity. I don't recall what powder that was with.

So after some some research, Speer #10, I tried using Dacron as a filler to keep the powder positioned up against the flash hole, and it worked like a champ. I used some Dacron filler from a pillow.

GS

 

[USSR]

After 117 years of Bullseye being used in .38 Special loads, I'd say you probably don't have to worry.

Don

 

[30Cal]

If by "pressure signs" you mean primers, well... They are poor indicators, esp in modern rifle cartridges. I've come to expect that they'll be flattened and sometimes slightly mushroomed in the nominal load zone. When you start seeing pierced primers or gas flowing around them, or signs in the brass itself (headstamp getting smashed or worse, imprints from the bolt), then it's definitely time to stop and think.

A chronograph is definitely a good thing.

When I get down into the "small pinch of powder" loads, I use dacron. Somewhere close to 0.3gr of it would probably be about right for a 38spl.

 

[Ex]

TiteGroup is a powder that specifically says on the container, "not position sensitive".
While I've never experienced this phenomena either, it does bear thinking about.

 

[Slamfire]

I am of the opinion that one should carefully think and research before going below recommended charge levels. While gigatonnes of Bullseye have been shot in the 38 Spl, and I really don’t consider the 38 Spl a big case, the guys creating reloading manuals have electronic pressure data coming out of the pressure gun real time. They will see inconsistencies in the pressure curve that tell them that combustion is not even or regular.

I think the highest risk is when people are using greatly reduced loads in large cases. While the 45 LC case is larger, what I have read on the web indicates that numerous Cowboy action shooters had pressure problems with small amounts of Bullseye in a 45 LC case. That is one reason Trail Boss was introduced. It is a bulky powder. Even with charges that produce low velocity loads it will fill the case. Whatever pressure curve and burning characteristics it has, it is likely to be more consistent than another powder that leaves a lot of case volume unfilled.

But with the 38 Special and Bullseye, I shot thousands of rounds with 2.7 grains Bullseye and a 148 LSWC. Shot great and nothing I could ever determine about it was position sensitivity.

 

[Walkalong]

Lead bullets do a lot better with powder position in pistol calibers than plated or jacketed. A load that drops 200 or 300 FPS with a plated bullet and the powder forward compared to back may not drop 50 FPS with lead and the powder forward compared to back. That is much harder to notice without a chrono.

 

[Toprudder]

I've had best results in 38spl (as far as powder-forward tests) with Titegroup and BE-86.

Lead bullets do a lot better with powder position in pistol calibers than plated or jacketed. A load that drops 200 or 300 FPS with a plated bullet and the powder forward compared to back may not drop 50 FPS with lead and the powder forward compared to back. That is much harder to notice without a chrono.

Interesting. I've not loaded any lead in 38, and don't plan to. While I'm not doubting your observation, I'm having a hard time trying to understand why this would be so. The only difference that I can figure is the friction each type has (lead is less friction). Seems that would equate to lower pressure with lead, everything else being equal, but I would think that would make things worse instead of better. Do you have any idea about why this happens?

 

[Walkalong]

No idea, except, as you surmise, they are slipperier. Just stating chrono results.

 

[horseman1]

I experienced some very erratic velocities and general performance with 45 lc years ago that was the result of powder position sensitivity. I don't recall what powder that was with.

So after some some research, Speer #10, I tried using Dacron as a filler to keep the powder positioned up against the flash hole, and it worked like a champ. I used some Dacron filler from a pillow.

GS

I have been wondering if that would work for quite a while. Glad to hear someone I trust has done it.

 

[USSR]

Some powders are just plain more lead bullet friendly than others. While you may use W296/H110 for jacketed bullet loads in .357 Magnum, 2400 or 4227 are much better lead bullet loads for that cartridge.

Don