Did my Bergara barrel just die.

[whatsupdoc]

WTF, So I have 1610 rounds through my B14 6.5 Creedmoor its a laser. Opened a new 8lb jug of H4350 yesterday and loaded a few under and over my standard load of
42.3gr H4350, 140 ELDM @ 2719 Fps.

My results were.
42.3 = 2642 77 FPS slower
42.5 = 2656
42.7 = 2665.

So today I go at it again
42.3 = 2662 57FPS slower
42.7 = 2665
42.9 = 2679.

Now with that being said this lot of H4350 is slower than my previous lot and in a 6.5 RPR.
Old Lot
42.3 = 2777
New Lot
42.3 =2741

I cannot believe 42.9gr of H4350 does not get me to 2700 FPS, I was expecting to rebarrel soon but I figured I had at least another 600 or so to go.
Could it be the powder? Or is there butter used in Bergara barrel alloy?

 

[308Gunner]

I have seen velocity loss from different lots I have also senn increases, I would just work up a load for that lot and shoot it till you see your groups open up and velocity drops. I tend to buy as much powder in 1 lot number as I can get to help with this.

 

[JCARL]

308's answer sounds more correct to me than butter barrel. Currently have 1,910 rounds that nearly copy your load on the same model rifle. No observed loss of velocity or accuracy.
Would be interested to hear what you find.

 

[Praeger]

It's not unusual to see variations in velocity when switching to a new canister of powder. Best practice is to buy as much as you think you'll need for a season in the same lot. If from separate lots, mix together (I'm only talking about if it is the same powder - just different lots) to equalize any nominal differences between two containers of alike powders.