350 Legend and AA11FS - a story of popped primers

[44Blam]

So, I made up 169 350 legend rounds with that Accurate 36-180LG boolit and 23.5 grain of AA11FS. (AA11FS is very similar to W296)
I've shot hundreds of rounds of this load and have not had any issues. Today, however, I had issues. Sadly, this was on a rifle stage of a match...


One of these primers got stuck in the upper and jammed in by the bcg. I had to take the buffer tube off because the bcg was stuck about 2" open.

So, I think I'll try out some different powders. I have been using W296 and AA11fs for a long time in 44 mag, but I get a full case. And I've always heard that W296 doesn't like case space and I was wondering about using it in this cartridge just because I was worried about the excess space. I'm thinking I just found out why you do not want to use these powders with a lot of space in the case.

I've got some HCFE BLK - > Hodgdons site shows that a full case will produce much lower pressure. And maybe look around to see if I can get some Norma 200...

[fastdadio]

How many loadings on that brass? Maybe the primer pockets were loose.

[44Blam]

How many loadings on that brass? Maybe the primer pockets were loose.

This was brand new Winchester brass. First loading.

[mehavey]

H110/W296 will spike badly if case not full. *
I heartedly recommend Norma-200 in its stead -- even if you have to order it.
https://www.midwayusa.com/product/1013086950
https://www.grafs.com/catalog/product/productId/18869
https://www.grafs.com/catalog/product/productId/18869

*Found this out most unpleasantly w/ both H110 and Lil`Gun

[44Blam]

H110/W296 will spike badly if case not full. *
I heartedly recommend Norma-200 in its stead -- even if you have to order it.
https://www.midwayusa.com/product/1013086950
https://www.grafs.com/catalog/product/productId/18869
https://www.grafs.com/catalog/product/productId/18869

*Found this out most unpleasantly w/ both H110 and Lil`Gun

I was quite happy with the W296 and AA11 loads until today. Only thing I can think of that was different was that it was fairly hot out there today ~90 degrees. Previously, I've shot those rounds at temps more in the 70 degree range.
I'm gonna be busy pulling bullets for a while. :-/

[tomme boy]

RL7 or 1680 would be my choice. Just don't compress the 1680.

[mulespurs]

I would be curious to know the case length of the hi pressure loads. Maybe measure those cases and see if case length had anything to do with high pressure.

Also if it was once fired Win brass I had to swage my primer pockets. I have a buddy that had primers breaking the face off the cup when depriming leaving a ring in the primer pocket, so a new primer wouldn't seat. He thought it was a hi pressure event but that was not the case.
The primers were so hard to seat that the cup fractured on depriming and was first blamed on high pressure.
After swaging primer pockets all was well.

[mehavey]

Gentlemen, this is pressure spike pure & simple.

As far as case length/involvement, I specifically moved to Winchester cases after doing significant comparison w/ the length uniformity and web thickness/floors of Win, Hndy, Starline, and Federal cases. 350 WIN cases (bought by the bag) were easily the winners.

I've experienced this same spike/results before when H110/W296 is loaded under 90% -- in this/mycase 80%.
It's insidious/more destructive in a gas gun because of the still-under-significant-pressure extraction process.
Word to the wise.

[ak_milsurp]

Gentlemen, this is pressure spike pure & simple.

As far as case length/involvement, I specifically moved to Winchester cases after doing significant comparison w/ the length uniformity and web thickness/floors of Win, Hndy, Starline, and Federal cases. 350 WIN cases (bought by the bag) were easily the winners.

I've experienced this same spike/results before when H110/W296 is loaded under 90% -- in this/mycase 80%.
It's insidious/more destructive in a gas gun because of the under-pressure extraction process process.
Word to the wise.

Why not try Alliant 2400?

Sent from my LM-V350 using Tapatalk

[45r]

I get my best accuracy using 20.4 H-4198 under a mountain mold truncated cone 215gc I had designed for a marlin 35rem.
I pc it for the AR.
1 inch 7 shot groups at 50 yards.

[44Blam]

I did a little analysis of the cases with blown primers, ones with partially blown (dark ring around primer) and cases that fired and look fine.

Note that the COL is the same for all of the rounds: 2.195" So, I don't think there was an issue with varying case capacity even with some minor variation in case length. Also, so far because I am still not sure of the pecularities of this round, I'm using a single stage press and a beam scale to measure each charge. So, the charge would have been 23.5 grain of AA11FS. This was a charge that I found to have the best accuracy and spread. The second best charge I tested was actually 24.2 grain of AA11FS...

New Case OK Case OK Case 2 Dark Ring Blown Primer1 Blown Primer2
UnSized 1.705 1.705 1.699 1.697 1.693 1.695
Sized 1.711 1.703 1.704 1.702 1.704
Primer Pocket 0.174 0.174 0.175 0.174 0.178 0.175

The first blown primer case had a slightly larger primer pocket but the second primer pocket had the same size as what I saw with brand new brass.
The second thing I noticed is that as cwlongshot mentioned, there is no real increase in case length after one firing and resizing. This is actually pretty interesting and good news for case prep!
The third thing I noticed was that the case with the dark ring and the two blown primer cases all had extractor swipes and very few of my other cases did - I found a few in about 300 cases.

I've shot 10s of thousands of 44 magnum rounds with W296 and a few hundred with AA11FS with zero problem. Never a blown primer and my velocities are very consistent. But I have basically a full case of powder under the boolit.

There was an old rumor that these powders would possibly generate pressure spikes when the case volume was not 90% or better and I am getting about an 80% or so fill in my cases with 350 Legend. I believe I may have seen this "rumor" actually generate a pressure spike.

[44Blam]

Why not try Alliant 2400?

Sent from my LM-V350 using Tapatalk

I may very well do some testing with 2400. I've got some downloaded loads for 44 mag and some mild 45/70 loads for Alliant 2400 that I found to be good.

[mehavey]

H4198 ?

[Moleman-]

Take a really good look at the case mouths. If too much crimp is used the case mouth can wedge into the freebore and cause a pressure spike.

[mehavey]

350 LGND does not utilize a crimp, per se.

Like any straightwall rimless, it headspaces on the mouth and
is simply tapered back to a nominal a 0.378" mouth.

(In fact I use the sizing die for that uniform taper)

[tomme boy]

You will run into a pressure spike very fast with 2400. You will have a 0.5gr increase and pressure will skyrocket. Plus you will not get any speed out of it. I have not tried it in a light bullet yet but it may be ok with a 124gr bullet.

[Moleman-]

350 LGND does not utilize a crimp, per se.

Like any straightwall rimless, it headspaces on the mouth and
is simply tapered back to a nominal a 0.378" mouth.

(In fact I use the sizing die for that uniform taper)

Spot on! I also have several straight walled rimless wildcats that my "taper crimp die" is the sizer I made for them with the decapping stem removed. For the others that are close enough to use a factory die set the crimp die is a gentle taper crimp like a lyman taper crimp die. Many die sets are sold with a short taper crimp that acts like a roll crimp and I will not use them. People that don't know better put a heavy enough crimp or if a cannelure is present they'll crimp them like they would with a 357Mag. That leaves an insufficient case mouth diameter to reliably headspace on.

[Packy]

I didnt have any primers fall out of wichester brass on 350 legend when shooting. But when i went to reload them, had some of the primers fall out after i seated them. Once fired brass. They showed no signs of pressure. Jacketed bullets and lilgun powder was the loads i was shooting. Have bought some starline brass but havent has time to go shoot them.

[cwlongshot]

I have yet to experience spikes from H110/296.... But WOAH Lil gun can give them!!!

I had some over pressure 296 loads myself. Not severe just hotter then I like in a AR.

What where primers 44? I use 450's nearly 100% accept for subs. (No need to waste them there)

I backed off what QL said was 54K load. Yet I still had some extractor marks and one primer fell out in my hand picking up brass. But it was a marked case. When I seat a primer and its looser then others generally I just mark brass and use it one last time. So Im not worried for the primer falling out. (Not seriously anyhow)

I like H110 but generally for what ever reason 296 is more common and last I bought a jug it was 296 on the shelf. So thats what I have.

I have t had luck with 2400 in this caliber. But 4198 is proving good as is RL7, With cast. 296 for jacketed.

CW

[mehavey]

H110 & W296 are the same powder.
Ejector brass flow/marks are evidence of hitting high 60s'/70ksi

Take care... surprises are bad juju at those pressures.