Sierra 116 TMK Load Data

[The Guide]

So we need to start acclimating powder like hardwood flooring before its installed.

It makes sense to me! Normalize it to the typical humidity that it will be stored and loaded at then you will get not only consistent burn rates but also more consistent powder charges as the powder won't lose water weight as it ages.

I have been normalizing all building materials on remodeling for a week minimum prior to installation for the last 2 years. Cracking, sagging, and misalignment repairs after doing the finish work has dropped to almost 0. Normalizing materials makes for a better finished product. I don't see why it wouldn't work for reloading.

Jay

 

[wind gypsy]

What I used to write off as powder lot to lot variation I realized was actually a difference in the powders humidity levels. Each new and sealed bottle I would open and use right away would be slower than my recent loads from powder that I’d been using for awhile. Where it’s manufactured is higher humidity than where I live. So now I get a new bottle and leave it open for two weeks to “dry out” now I haven’t honestly had a measurable difference from lot to lot.
Could be something worth trying when going from a bottle you’ve had awhile and has been opened/exposed lots to a new sealed bottle.

I believe that there is something to that but maybe variance of humidity in the manufacturing location has "lot to lot" changes as well?

I had a bunch of 1# bottles from 10 years ago and some of them recently were loaded up basically immediately after breaking the seal for the first time. 8#er purchased about a year ago had the seal broken and loaded immediately after old (but newly opened) lot and I got a 60 FPS increase with same charge.

I lived/worked in central CA for a while and didn't worry about leaving powder in hoppers for multiple days and never noted any issues. I did the same after moving to south carolina and i was shocked at how much velocities dropped after leaving retumbo in the chargemaster for a week or two.

 

[Hydra6]

First try with 116TMKs. 6 Dasher, 27.5 inch barrel plus supressor. High round count barrel (2300+). A 105 Mtach Burner group for fouling plus my standard 105 Hybrid match load. Will bump up powder charge and try some more.

 

[jonnyviceroy]

I believe that there is something to that but maybe variance of humidity in the manufacturing location has "lot to lot" changes as well?

I had a bunch of 1# bottles from 10 years ago and some of them recently were loaded up basically immediately after breaking the seal for the first time. 8#er purchased about a year ago had the seal broken and loaded immediately after old (but newly opened) lot and I got a 60 FPS increase with same charge.

I lived/worked in central CA for a while and didn't worry about leaving powder in hoppers for multiple days and never noted any issues. I did the same after moving to south carolina and i was shocked at how much velocities dropped after leaving retumbo in the chargemaster for a week or two.

Yeah I think you’re right forsure about where it’s manufactured. I figured out where the hodgdon extremes were made (Mulwala Australia). With a notably higher baseline humidity level than where I live in Utah. So that’s where I started doing the 2 week “drying period” before using a powder to load and attempt to keep things consistent.

 

[MT_Wyatt]

6 creed, 18” 1:7 Preferred prefit setup from @hereinaz. Started at 2.85 and tested 40, 40.5 and 41 gr but bumped to 2.9” COAL, retested at 40, 41, 41.5 gr of H4350. 2893 avg Vel @ 41.5 grains and pretty stupid 5 shot group, going to roll with it. None of the test groups were “bad” but 40gr at 2.85” was best first go, this the 2nd.

 

[HighUintas]

Yes, the Hornady guys mentioned in one of their podcasts that humidity in air will affect moisture in powder and this the speed.

I completely forgot about it so I'm haven't acclimated my powder but it's been a long time since I have opened new powder.