Question re new vs old H4350 lot

[DownhillFromHere]

Just cracked a new jug of H4350 and loaded a few test rounds to compare against identical loads with the old jug - same everything except powder.

The new powder lot is 30-40fps slower than the old (6.5CM, 41.2gr H4350, Starline SRP brass w/ CCI450, 140gr Berger Hybrids, 140gr Hornady ELD-M, old/new tested within minutes of each other).

Question: can I expect accuracy to be the same at distance if I increase the new powder charge to match the old powder's velocity? I would expect that to be the case, but I'm interested in others' experience in case my assumption is wrong.

 

[Govt Mule]

I have experienced the same with different lots of 4350. Especially going from a jug that was about 4 years old to a lot # that was 2 years old. I test the new lot at 100 yards with increments of .02 grains and see if it one-holes the groups that approach the old lot's velocity. Take the group that shoots the best and try it at distance.

 

[Steel head]

I’ve seen even bigger changes with H4350.
New powder could be wetter than old stock as well.

 

[DownhillFromHere]

Thanks guys... to be clear, I am well aware of probable charge/velocity differences from one lot to another.

The question is, if I increase the "slow" powder charge in order to match velocity from the "faster lot, can I expect identical accuracy at range, or am I likely to go through development again?

Example: 41.2gr of "old" lot gave me 2745fps with the 140 ELD-M; the new lot gives 2708fps. If I bump the new lot charge to 41.5gr and get the 2745fps, can I expect the same accuracy as with the lower old charge at the same velocity?

Yeah, yeah, I know, the target tells the story at the end of the day.....

 

[Ocean_Dweller]

I think you will be fine if match your velocity. I actually had the opposite happen to me last month with my sons 6.5 creed using 135 Berger Classic Hunters and H4350. I had a fantastic tuned load in his gun that would group sub .5moa consistently with an SD of 3. Switched lots and the load became way too hot, bolt sticking, and SD was 32 with a 64fps velocity increase! Had to drop the charge .4grs to get the same velocity. Once I did, the SD and accuracy came right back.

 

[Jmkjr87]

My experience with H4350 is the new stuff is hotter than the old. I had to drop 1 whole grain of powder to get the same speed as the old stuff

 

[DownhillFromHere]

My experience with H4350 is the new stuff is hotter than the old. I had to drop 1 whole grain of powder to get the same speed as the old stuff

Heh. To give an idea as to the age of this newly-opened H4350 jug - it came from an LGS and the price sticker on it is $205; it got pushed behind some pistol powder I haven't touched in over two years. So I'm sure the rest of my stash is much newer and maybe hotter....

 

[Cascade Hemi]

Humidity. Leave the jug open on your bench for a week and retest.

 

[Jmkjr87]

Heh. To give an idea as to the age of this newly-opened H4350 jug - it came from an LGS and the price sticker on it is $205; it got pushed behind some pistol powder I haven't touched in over two years. So I'm sure the rest of my stash is much newer and maybe hotter....

My old stuff has a metal lid and the new has plastic lid. All I got are 1lbs jugs

 

[NiteQwill]

Humidity. Leave the jug open on your bench for a week and retest.

This is what I do.

Edit: I should add that I only do this a constant humidity room in my house.

 

[Jmkjr87]

This is what I do.

Wouldn't that add humidity? Is that what your going for

 

[NiteQwill]

Wouldn't that add humidity? Is that what your going for

You're looking for stability. Lots of ELR shooters do it to stabilize powder lot to lot.

I also usually just mix all my powder together in 8# jugs. All different lot numbers. Ymmv

 

[smoothy8500]

Humidity. Leave the jug open on your bench for a week and retest.

Maybe not necessarily humidity, but new powder has more solvents like alcohol or acetone that evaporate.

 

[Jmkjr87]

Maybe not necessarily humidity, but new powder has more solvents like alcohol or acetone that evaporate.

So your letting excess shit escape. Got ya

 

[NiteQwill]

How does humidity affect powder?

You may have heard about a relationship between humidity and bullet velocity either in a book, on a reloading forum, or from a crusty benchrest shooter right after saying they get better ES/SD&#821…

chronoplotter.com

 

[Cascade Hemi]

Maybe not necessarily humidity, but new powder has more solvents like alcohol or acetone that evaporate.

Can you support that claim? What you're saying is counter to my experience. I've seen powder turn bad but never off-gas acetone or alchohol.

 

[Bacarrat]

Pretty interesting video about how humidity does affect your speeds

 

[smoothy8500]

Can you support that claim?

No, I'm too lazy to Google nitrocellulose or single-base smokeless powder manufacturing and list the solvents used.

 

[whatsupdoc]

Pretty interesting video about how humidity does affect your speeds

And this was done overnight, leave it out for a month and test.

Hodgon 8LB containers have no seal on the cap, even new unopened ones have the foam seal loose half the time.
If the container is stored in a humid environment then the humidity will most likely alter the performance of the powder. Too dry an environment will most likely move it in the opposite direction.

Vihtavuori powder containers at least have a seal on the cap.

 

[AnimalMother224]

And this was done overnight, leave it out for a month and test.

Hodgon 8LB containers have no seal on the cap, even new unopened ones have the foam seal loose half the time.
If the container is stored in a humid environment then the humidity will most likely alter the performance of the powder. Too dry an environment will most likely move it in the opposite direction.

Vihtavuori powder containers at least have a seal on the cap.

in my time reloading and the considerable amount of powder I have gone through I havnt come across a single powder storage container from any manufacturer, when new, not have a glued barrier as a seal. ive always had to peal it off.

 

[whatsupdoc]

in my time reloading and the considerable amount of powder I have gone through I havnt come across a single powder storage container from any manufacturer, when new, not have a glued barrier as a seal. ive always had to peal it off.

Hodgon 1 LB have a foam seal and a seal on the lid, the 8 LB have a foam seal but no seal on the lid so
when you remove the foam seal (I have had these loose quite a few times) there is no seal.

 

[AnimalMother224]

Hodgon 1 LB have a foam seal and a seal on the lid, the 8 LB have a foam seal but no seal on the lid so
when you remove the foam seal (I have had these loose quite a few times) there is no seal.

I havnt experience the foam seal not being at least a little stuck on the mouth. ill have to double check next time I open one up.

 

[Cascade Hemi]

in my time reloading and the considerable amount of powder I have gone through I havnt come across a single powder storage container from any manufacturer, when new, not have a glued barrier as a seal. ive always had to peal it off.

None of the 40 1lb Hodgdon containers I've bought in the last 12 months have been sealed. The foam was present but unattached.

 

[rottenruger]

Just cracked a new jug of H4350 and loaded a few test rounds to compare against identical loads with the old jug - same everything except powder.

The new powder lot is 30-40fps slower than the old (6.5CM, 41.2gr H4350, Starline SRP brass w/ CCI450, 140gr Berger Hybrids, 140gr Hornady ELD-M, old/new tested within minutes of each other).

Question: can I expect accuracy to be the same at distance if I increase the new powder charge to match the old powder's velocity? I would expect that to be the case, but I'm interested in others' experience in case my assumption is wrong.

Damn! Too many variables out there!!!!

 

[rottenruger]

Just cracked a new jug of H4350 and loaded a few test rounds to compare against identical loads with the old jug - same everything except powder.

The new powder lot is 30-40fps slower than the old (6.5CM, 41.2gr H4350, Starline SRP brass w/ CCI450, 140gr Berger Hybrids, 140gr Hornady ELD-M, old/new tested within minutes of each other).

Question: can I expect accuracy to be the same at distance if I increase the new powder charge to match the old powder's velocity? I would expect that to be the case, but I'm interested in others' experience in case my assumption is wrong.

EGADS!!! I missed the obvious question....... WHERE did you find a new jug of 4350???

 

[bgavin]

None of the 40 1lb Hodgdon containers I've bought in the last 12 months have been sealed. The foam was present but unattached.

Same here.

 

[AnimalMother224]

I have 20 or so of these Varget pounders and I checked 5 of them. you can see where I tried pealing it off. This inconsistency is bothering me

Ill have to check my kegs now, y'all got me paranoid.

 

[smoothy8500]

I’m guessing that if the cap is tight enough it’s going to seal the layer of foam against the jugs rim.

 

[Grant77]

EGADS!!! I missed the obvious question....... WHERE did you find a new jug of 4350???

EXACTLY! I’ve been searching like a MFer for months and come up with zippy

 

[Grant77]

Same here.

Me too, dating back a lot longer than 12mo on my end tho. The first time I noticed it I was SURE it had been tampered with…then it was every other or every third I opened had a foam disc hanging by a thread.
I’m quite surprised that Hodgdon has remedied what seems like a very easy fix in order to ensure their powder isn’t compromised by humidity/contaminates

 

[NiteQwill]

EXACTLY! I’ve been searching like a MFer for months and come up with zippy

It's available. I've bought 2 8# jugs of H4350 in the last 2 weeks from Powder Valley. Not impossible but you need to subscribe to notifications from the usual suspects.