Reduced Velocity When Cases Split?

[NiklasP]

Hello!

I had a new experience yesterday while testing heavy 357 Mag loads. Load was 13,8 grains H110, 180 grain Nosler Partition bullets, Rem Ni-plated 357 brass, Federal SMP, muzzle velocities avg 1200 fps, gun is a Ruger Blackhawk, 6,5 inch barrel. Chamber pressures near max for 357 Mag. On very first shot sound was "hollow" and velocity was 1085 fps, recoil was lighter than usual and bullet hit target lower than other two shots. Later I had another such "hollow" sounding shot, again low velocity and low POI. When I removed empty brass from cylinder, two had sidewall splits, one about one cm long, other almost full length of case (this one took some effort to extract). Other 4 cases extracted easy and dropped back into chambers under their own weight. No damage to chambers seen visually. All primers visually identical and same visually as for slightly lighter loadings. This was 2nd loading of these cases, which had been full-length resized each loading. Next time I will check cases immediately after such an event.

Anyone else experienced this combination of "hollow" sound of shot, major sidewall splits and sharply lower velocities? Although these two events indicate no safety problem, they are negative indicators of reliability of these cases for hunting loads, because of their lower velocities and POIs.

I seldom use Ni-plated brass. In this case I have about 20 once-fired Remington and S&W Ni-plated 357 Mag cases, which I chose to use for these loads so that they can be readily distinguished from my other loads. Previous use of mixed 38 Spl Ni-plated brass for low-pressure HBWC loads resulted in far few loading of Ni-plated vs standard brass cases before sidewalls split.

Thanks,
Niklas

 

[Skip Sackett]

Two things to check. You said that you used 38spl cases in this gun. That is fine but make sure the carbon ring is gone from all chambers. This could be a big problem if you are loading near maximum already.

Another thing to note is where the case split. If it is at the mouth, it can be from working the brass to make a firm enough crimp to keep the bullet from jumping.

Ni-plated cases are inherently more brittle. They will take fewer loadings at full power loads especially if you full length resize which is a necessity for handgun loads, in my opinion.

Check your cases well before loading and stop when you encounter a change in sounds of felt recoil. Remove all bullets and check for barrel obstructions. Had the lead core hit the target and the copper jacket stayed in the barrel, you would be buying a new gun, maybe an eye patch too!

Food for thought!

 

[OKFC05]

Anyone else experienced this combination of "hollow" sound of shot, major sidewall splits and sharply lower velocities? Although these two events indicate no safety problem,

You were lucky. Those loads are too hot for those cases, and they are a safety hazard. You need better cases for max loads, and you may well be over max in your gun. Greater than usual velocity often correlates with higher pressure.

 

[NiklasP]

Well, I was hoping for information re similar experiences from others. Got nothing of that in first two responses.

I agree that I really do need to use cases that are not going to suffer cracks in sidewalls, cracks extending nearly the full length of cases, after only two reloadings. Actually, in 50+ years of reloading, often high pressure calibers, I have never previously had major splits in case walls, even after 20 reloadings and full length resizing (neck splits, yes). I am leaning strongly toward using new Remington plain brass cases for next round of test shooting, using this same load weight.

To correct some misreadings of what I posted:
1) There was no problem with "carbon rings" in chambers when these loads were fired -- "carbon rings" had been totally cleaned out in preparation for shooting heavy 357 Mag loads.

2) Splits are clearly noted as in sidewalls of cases that had only been resided and reloaded twice. I have only previously had such large splits with 38 Spl Ni-plated cases and low-pressure loadings, in all of my 357 Mag revolvers -- however, I have no audio or velocity data for those split cases, and they were many.

3) Bullets clearly noted to be Nosler Partitions, so no shooting of cores through flimsy jackets. Also noted that bullets did impact target, making normal bullet holes, just somewhat below where rest of groups was, and, not noted, below where lighter loading had impacted on previous test shooting. Other 4 rounds went into nice round, small groups, as small as I ever shoot with this gun. I agree that I should have checked bore after each of these shots -- it was the clean, normal-looking bullet holes in target that influenced my judgement in these two cases, as has been case before.

4) The two rounds of concern, out of six, actually had LOWER velocities AND impacted LOWER on target. This is known because target was checked after each shot, so, I had velocities AND impact points for each shot. What is surmised from correlating evidence, simply because I did not check cases after each shot -- my fault -- is that the split cases and low velocities were on same shots. Other 4 rounds had velocities clustering closely around 1200 fps, up about 50 fps from tight cluster of velocities from previous, slightly lower loading, which also gave nice tight groups.

5) Based on identical visual appearances of primers (I know an iffy art at these low pressures of about 40.000 psi, especially with soft primer cups of Federal primers) for this and previously lower loadings, there is no indication of excessive pressures. Ditto for easy extraction of cases, which then fall back into chambers under their own weight.

6) FYI -- and not noted in my initial post -- recoil of this load is nicely less than recoil of another load being tested in same shooting sessions. That load uses Hornady XTP 158 grain bullets over 14,0 grains of 2400, a good 1 to 2 grains less than listed in various, widely used loading manuals from bullet or powder makers, plus Lyman's 47th. That loading chronos at 1350 fps average, shoots as small groups as I can shoot with this revolver, and cases drop from chambers, primers are visually same as for load with Nosler 180s. Muzzle energies of this 158 grain load are much higher than for the 180 grain loads, consistent with differences in recoil.

7) Not noted is that this Ruger gives velocities up to 250 fps higher than my other two 357 Mag revolver for more or less full loadings, with only part of this difference reasonably result of shorter (4,6 and 5,0 inch barrels).


Thanks!
and
Looking for more directly relevant feedback.

Niklas

 

[OKFC05]

Well, I was hoping for information re similar experiences from others. Got nothing of that in first two responses.

I have had dozens of split cases, and seen hundreds of them in competitions. Results ranged from nothing to destroyed guns. Most common damage was magazines blown out of semi-autos to bulged barrels when bullet got stuck in barrel. I have seen one Glock and another similar gun (don't recall brand) blown into junk from a failed case. If the loads keep splitting, clearly the cases are too weak for the load, no matter what "should" be happening. One shooter who kept blowing cases in a match was irate when I "DQed" his ammo and told him to get different ammo, but we found out later he was using ammo that had been seriously over-loaded.

I thought you understood I was speaking from experience and not just speculating. A hot load that keeps blowing cases is just not worth the risk. A mild load splitting an old case is less destructive, but you still need to stop and inspect the gun if the report sounds weak. The SO saying is "If it goes POP, STOP."

The .38 cases that have split in my 66s and 686s did no damage. I don't load full-house .357s in anything but once fired cases, so have never split one of my reloads. I did split some factory loads, and discarded the rest of the box.
Based on my experience, if the report sounds funny, stop, unload and inspect the gun. The buldged barrel guns resulted from shooters who kept shooting with the Safety Officer calling "Stop."

 

[mtgianni]

The proper thing to do with a split case is to flatten it and retire all others of the same lot. You do keep lots together and record the number of times fired don't you? This lot is too brittle, worn or does not stand up to this pressure for what ever reason. It is time to retire the entire lot.

 

[NiklasP]

Thanks OKFCO5!

I thought I was "safe" with once-fired 357 Mag Remington Ni-plated cases, and they did survive for one reloading. Trash can is next stop for all these cases, once-fired or not. I have enough new Remington plain brass cases for all future test shooting of this load -- they are what I will use.

No more Ni-plated cases for me.

Thanks again,
Niklas

 

[NiklasP]

You do keep lots together and record the number of times fired don't you?

mtgianni,

These are the first "high pressure" cases that I have ever had split in sidewalls, so, I was more than a little surprised when I took empties out of cylinder. It has been life-long practice to note # of reloadings with high pressure rifle calibers (such as 7X57, 7X57R, 7X51 -- my most heavily used rifle calibers over 40 years of shooting) -- eventually, split necks weeded these down, after 10 or more reloads and remaining cases went to trash. This brass was all top of line, Norma for 7X57R, Remington or Federal for the others -- there was never a reason to be especially leary of quality of brass.

All other splits in case walls, in my decades of shooting, have been result of tens of reloadings, and resulting work hardening of brass, with low pressure loading, such as 45 Colt, 45 S&W, 44-40, 32-20, 38 Spl., etc. Even these were few. These were BP loads or nitro loads at similar chamber pressures. Normally, neck splits from belling and crimping are the common eliminators.

My previous practice with higher pressure loadings for 45 Colt, 44-40 has been to start with new brass and only reload once. I have now added 357 Mag max load to that list. This practice has long been SOP for all hunting loads -- and these 357 max loads are for that, so, back to old practice again.

Thanks again,
Niklas

 

[NiklasP]

I thought you understood I was speaking from experience and not just speculating. A hot load that keeps blowing cases is just not worth the risk. A mild load splitting an old case is less destructive, but you still need to stop and inspect the gun if the report sounds weak. The SO saying is "If it goes POP, STOP."

OKFCO5,

I did understand that you were speaking from experience and not just speculating. Your second post is just the kind of response I was expecting -- and it has been useful. Thank you!!

I did check bore of gun for bulges -- none. I did find one chamber that had thin lines of powder residue in much the same long pattern as the one case split and a second one with a cm-long straight line of powder residue. Both scrubbed out totally with bore brush in just a few passes. Other 4 chambers have only usual amount of powder residue near mouths. SO, it would appear that high pressure powder gases spread very little distance from location of splits, perhaps accounting for observed about 120 fps decrease in recorded velocities and a few inches lower POI for these two shots.

In no case would I call either of these muzzle reports "POPS", really it was that they sounded "hollow" rather than normal 357 Mag "CRACK" -- and recoiled noticably less, but not at all lightly. I agree, POPS mean STOP and check. When I saw a normal-looking bullet hole in target each time, I quit worrying about bullet stuck in bore. I would wonder if a range officer would have noticed?

Hopefully, elimination of Ni-plated cases will remove this bothersome feature of these otherwise very satisfactory loads with 180 grain Nosler Partition bullets.

Thanks again,
Niklas

 

[TSQUARED]

Nckel plated cses are inherenbtly more brittle and will split with fewer reloadings than brass cases. I have noticed that the Remington mnickel plated cases split after fewer reloads than Winchester or Federal nickel plated cases.

 

[Rule3]

I have had cases split down the side in 357 while chronographing the loads and there was clearly a drop in velocity on the rounds that split.

These were in fact Rem Nickle plated that had been reloaded many times or very old. I believe they came from a batch of loaded ammo I broke down.

 

[Jellybean]

When the cases split it might create more space for the gases to fill up, which would lower pressures. It would be pretty much the same as seating the bullets out further than normal.

 

[fredj338]

Brass cases split, heavy loads, light loads, it just is what it is. The nickel cases seem to be worse, I think the plating process makes them a bit brittle. The case splitting is the casue for the lower vel, the bullet is released early, case pressure drops, velocity drops. I suggest for hunting laods, you use new or once fired cases only to prevent that.

 

[NiklasP]

Fredj338,

My prime suspect for the lower measured velocities is, like yours, early or easier bullet pull. All these loads were as heavily crimped in channelure as I could.

I agree with your suggestion of using new or once fired cases for heavy hunting loads -- that has been my practice with heavy hunting loads for central fire rifle calibers, as well as with heavy 45 Colt and 44-40 loads. I will be using new Remington brass for ALL further testing and for resulting hunting ammo. That practice has proven very economical-- over many decades, only 1 round is used to check POI shortly before actual hunting and only 1 round has been use to take whatever critter I was hunting. After a lifetime of one-shot kills, two seasons ago I had to use a second shot because the first just missed the spine, putting the critter down but not stopping it -- second shot did it right.

No more Ni-plated cases!!! I have never needed them in well over 50 years of hunting, trail carry and reloading -- I sure won't need them for the next 10-15 years I may still be able to hunt, etc.

Thanks also to Jellybean, Rule3 and TSQUARED!! It is comforting to learn that others have same experience and explanations of what did or very likely did happen. This was first time I had split cases when chronoing -- I am kicking myself for not checking the brass for those two shots giving lower velocities.

Thanks again to each person that took time to respond,
Niklas

 

[Rule3]

Fredj338,

My prime suspect for the lower measured velocities is, like yours, early or easier bullet pull. All these loads were as heavily crimped in channelure as I could.

I agree with your suggestion of using new or once fired cases for heavy hunting loads -- that has been my practice with heavy hunting loads for central fire rifle calibers, as well as with heavy 45 Colt and 44-40 loads. I will be using new Remington brass for ALL further testing and for resulting hunting ammo. That practice has proven very economical-- over many decades, only 1 round is used to check POI shortly before actual hunting and only 1 round has been use to take whatever critter I was hunting. After a lifetime of one-shot kills, two seasons ago I had to use a second shot because the first just missed the spine, putting the critter down but not stopping it -- second shot did it right.

No more Ni-plated cases!!! I have never needed them in well over 50 years of hunting, trail carry and reloading -- I sure won't need them for the next 10-15 years I may still be able to hunt, etc.

Thanks also to Jellybean, Rule3 and TSQUARED!! It is comforting to learn that others have same experience and explanations of what did or very likely did happen. This was first time I had split cases when chronoing -- I am kicking myself for not checking the brass for those two shots giving lower velocities.

Thanks again to each person that took time to respond,
Niklas

There really is no way to know when or if a case will split on the side. It just will. The case mouth you can see if it is starting to split or dented or somehow deformed. Out of hundreds or even thousands I have only had a handful split.

 

[dickttx]

I had a half box of 357's that I had reloaded in 1970. Winchester once fired nickle cases, Hornady jacketed soft points, don't remember the load right now, but it was not excessive.
I had not shot my 357 Colt MkIII in a number of years.
When I finished shooting and dumped my cases I found that 19 of the 25 had splits. Went back to the reloading room and dumped all my nickel cases in the trash.
I also had 45 colt reloads that old, in brass cases, and had no problems with those. I did have a 45 colt brass case (new Rem bought in 1970) split on the first load. Still using the other 49.
All my reloading equipment, ammo, and guns had been pretty much packed away for 40 years until I retired about a year ago.