why you must rework when changing components or lots

[308sako]

A recent experience with AR Comp nearly cost me dearly. Been loading for 50 years and this is the greatest amount of change I have witnessed. Having burned 10 pounds of previous lots, I mistakenly had confidence in the most recent replacement. Shooting a favored load which was under maximum , suddenly I was blowing primers. Using my Oehler 35P I have found that 1.8 less grains gives the same velocity as the prior load. However the precision is not the same because the harmonics have changed. Live and learn.

[Koshinn]

A recent experience with AR Comp nearly cost me dearly. Been loading for 50 years and this is the greatest amount of change I have witnessed. Having burned 10 pounds of previous lots, I mistakenly had confidence in the most recent replacement. Shooting a favored load which was under maximum , suddenly I was blowing primers. Using my Oehler 35P I have found that 1.8 less grains gives the same velocity as the prior load. However the precision is not the same because the harmonics have changed. Live and learn.

Interesting, I also loaded a few rounds of AR Comp and was blowing primers when almost at a factory amount of powder. I'm in LV too... where did you get your AR Comp?

[308sako]

Sportsman's whorehouse

[CrazyIrishman]

this worries me... I got two 8 pound jugs left from the same lot of ar comp and a 77 grain load that's a little past 23 grains , kinda reaffirms what I told myself the other day is that I've pushed my luck to the point of it pushing back in my life and with all the hot loads I have that have stayed very similar for lot to lot that I have just gotten lucky. Kabooms do happen, few years ago I saw a gentleman get seriously injured when his race gun literately supernova'd on itself (best way to honestly explain it.)

[308sako]

this worries me... I got two 8 pound jugs left from the same lot of ar comp and a 77 grain load that's a little past 23 grains , kinda reaffirms what I told myself the other day is that I've pushed my luck to the point of it pushing back in my life and with all the hot loads I have that have stayed very similar for lot to lot that I have just gotten lucky. Kabooms do happen, few years ago I saw a gentleman get seriously injured when his race gun literately supernova'd on itself (best way to honestly explain it.)

XBR a little past 23 grains warms up quickly, AR Comp is usually found closer to 22 grains with 77 SMK's FWIW

[markm]

AR comp is Reloader? Or Alliant? In either case... I won't run ANY powders from either of those brands.

In any case... you're findings are interesting. I had this happen with an XBR load too. I could only guess it was a lot change... but I couldn't prove it. XBR is good powder, but it does turn on you quick when you're over max.

[CrazyIrishman]

XBR a little past 23 grains warms up quickly, AR Comp is usually found closer to 22 grains with 77 SMK's FWIW

exactly why I feel like I'm pushing my luck... Also does alliant have some serious quality control issues or is this just a freak incident? I understand that the powders octane/burn rate varies from lot to lot, but the op seems to have a batch that's pushing the same velocity with 1.8 grains less than prior lots and I got 23.2 grains and I don't have velocities near what I was expecting... actually its disappointing for a load that's supposedly made for the ar and heavy loads.

[308sako]

For what it is worth, I'm swearing at and off this brand of powders due to the lack of consistency. IMR's 8208 XBR showed a little of this in early lots, but has become far more stable in my experience. Varget is also prone to small variations which are to be expected, however an approximate eight percent change in charge weight is not acceptable to me.

[markm]

No kidding. I too have read about the Varget variances, but still use it. But Alliant and Reloader have always just had the red headed step child status in my mind.

[Waylander]

I've had zero problems out of Alliant Reloader 7 and 10x. Both are sub MOA consistently.

YMMV.