Powder fail to ignite

[Walkalong]

SNS coated 158 Gr SWC (SWC: .358/3585 & .712+/- )
14.5 Grs 2400. Medium plus roll crimp.
CCI 500 Primer.
1.605 +/- .001 OAL.
85 Degrees, 68% RH. Cloudy.

4" 586
Powder Back Powder Forward Powder Level 6 shots each
HI 1278 1298 1289
LO 1178 1234 1193
AVG 1234 1257 1241
ES 100 64 96
SD 35 25 38

Hornady 158 Gr XTP
14.5 Grs 2400
CCI 500 Primer
1.577 OAL.
72 Degrees 26% RH

6" Trooper Mk III
Powder Back Powder Forward Powder Level 6 shots each
HI 1253 1254 1241
LO 1098 1075 1169
AVG 1195 1196 1202
ES 155 179 72
SD 53 67 29

2400 does very well with the powder away from the primer. These are tame compared to some of you high rollers using W-296/H-110, but they are very accurate and I like them. Nice recoil, you know you shot something, but not sharp.

 

[ATLDave]

The thing I don't fully understand yet is why the bullet tension in the case makes such a dramatic difference in how the powder ignites. It really doesn't make sense to me. I don't understand how you can have this same powder in other loadings where the case is half full of powder and yet the powder ignites and burns just fine, and in this case allowing the bullet to move forward into the forcing cone before the powder is fully ignited causes very inconsistent and low velocity, and in one instance at least is the possible cause of the powder failing to ignite at all. You would think the two situations would produce very similar results.

I wonder if the reason that the one charge did not ignite is because the bullet had made it all the way across the cylinder gap just from the primer explosion, and once the cylinder gap was opened up all the pressure was lost and the burn fissled out?

I think the latter is a big part of it.

Take some powder - an amount similar to a cartridge loading - put it on some pavement outside (away from flammable materials) and light it. It will burn, quickly and vigorously, but it will not pop or bang; most of the time it won't even crackle or sizzle audibly. Powder burns dramatically differently under different pressure conditions. (This happens to be one reason that different burn rate charts don't have stuff all in the same order - they are likely testing at different pressures.)

A bullet in a long, single-ended tube (like the barrel of a locked-breach, single chamber gun) is just not similarly situated to a bullet that has jumped across a gap in terms of the pressure condition it leaves behind it.

 

[Walkalong]

I think your FL die has not done its job.

I had the same problem with my first .38/.357 sizer. I bought an RCBS and it is perfect. The expander has to do its job now. It wouldn't even tough the inside of some thin brass with the first sizer.

 

[Jack B.]

SNS coated 158 Gr SWC (SWC: .358/3585 & .712+/- )
14.5 Grs 2400. Medium plus roll crimp.
CCI 500 Primer.
1.605 +/- .001 OAL.
85 Degrees, 68% RH. Cloudy.

4" 586
Powder Back Powder Forward Powder Level 6 shots each
HI 1278 1298 1289
LO 1178 1234 1193
AVG 1234 1257 1241
ES 100 64 96
SD 35 25 38

Hornady 158 Gr XTP
14.5 Grs 2400
CCI 500 Primer
1.577 OAL.
72 Degrees 26% RH

6" Trooper Mk III
Powder Back Powder Forward Powder Level 6 shots each
HI 1253 1254 1241
LO 1098 1075 1169
AVG 1195 1196 1202
ES 155 179 72
SD 53 67 29

2400 does very well with the powder away from the primer. These are tame compared to some of you high rollers using W-296/H-110, but they are very accurate and I like them. Nice recoil, you know you shot something, but not sharp.

Alliant 2400 is the only powder I use in .357 Magnum along with wspm primers and 125gr. jacketed bullets. Trooper MKIII & GP100 both 6 inch. Have tried every thing from Hodgdon,IMR and VV always come back to good old 2400. If I load down I go with Unique.

 

[Jack B.]

I went and bought a pound of 2400 yesterday to try in 357 magnum and 357 maximum. I loaded up some loads to shoot last night with 158 gr jacketed hp's and went out this afternoon to do some chronograph testing. The 3rd shot went pop instead of boom and a small trickle of smoke came out the cylinder gap. I opened the cylinder to find the barrel crammed with powder and the bullet lodged half an inch into the barrel.

View attachment 768419

There was slug of powder in the end of the cylinder about 1/4" deep as well.

View attachment 768420

Cases were dry tumbled in walnut for a few hours directly prior to loading. This is the 4th or 5th firing I believe on this brass. Cases were then sized, primed, loaded, and a heavy crimp applied with a Lee factory crimp die. This case had 14gr of 2400 and an S&B SP primer. I do not touch the primers on there way from the package to the priming system. I know the flash hole could not have been blocked because they were deprimed at the same time they were loaded. Inspection of the fired case showed no signs of walnut media, just un ignited powder. Obviously the primer went off with significant force to drive the bullet and powder column into the barrel but somehow did it not ignite the powder. This is the 2nd time I have had this happen in 357 magnum. The first time was with AA7 and a 158 jacketed. I don't remember what primer was used but most likely the same lot of S&B SP primers. In that instance the bullet was the same distance into the barrel and the unignited powder was yellow colored and looked wet. I assumed in that instance that I must have had a drop of water in the case which were loaded without cleaning from the last firing. In this case I know there could not possibly have been moisture in the case since they came right out of the tumbler and were loaded. Here is the bullet after driving it back out the barrel with a brass rod.

View attachment 768421

I fired the rest of the 47 cases loaded without issue and was impressed with the accuracy and low pressures. I like this powder. Anybody here test 2400 with magnum and non magnum primers for consistency? I've shot a few thousand of these primers with 700x and bullseye which are both very easy to ignite, but I may just save the s&b's for 700x and get some different primers for 2400. I keep federal small pistol magnums on hand for Win 296.

Could be just the photo's angle but primer looks crooked to me.

 

[mdi]

I can't agree the primer failed. It drove the bullet into the barrel so it seems it fired at full power. It was the powder that failed to ignite.

A "failure" doesn't mean a total failure to ignite. Failure meaning not reaching it's full potential/power. My post ment the primer could have been the problem. Perhaps a "quick" flash of insufficient brisance, or a too small charge of compound. Besides it's a moot point anyway as one out of 50 isn't enough to support any "theory" or WAG. I know it can be "difficult" to read just the black letters and not read between the lines...