h4831sc velocity question

[phutch30]

Ive been working with some loads with H4831sc/180 gr accubonds and my velocities seem pretty low.

300wsm
brux 4 grove 24" barrel ~35 rds total thru the barrel
CCI 250 primers
fed brass
35-45 degrees


thru a chroni

68grs - ave-2822
68.5grs - ave-2863
69grs - ave 2871

I realize you may or may not see the velocities posted in reloading guides but I'm pretty far under posted speeds. Wondering if my chroni is wacked

 

[excaliber]

I found the same thing with 180 gr Accubonds in my 300 win mag. The accuracy was fine but H4831sc was at least 50 -75 fps slower than RL-22 all things being equal.

 

[PGJPJ]

I use H4831sc in my 300 win mag with 200 grain Partitions. I also don't get the best speed with that load, but very good consistency. I tend to think that's the general findings with that powder.

IMR 7828 or RL 22 would probably get you more speed if that's what you are looking for.

 

[918v]

I don't load for WSM but in my WM increasing oal and decreasing jump increases velocity and I'm nowhere near the lands, about .060" off.

 

[N2TRKYS]

I used it in my 7 SAUM w/ 160 grain Accubonds. It came in about 200 fps slower than other pwders. Accuracy was good, but only reached about 2660 fps out of a 22" barrel.

 

[wklman]

Ditto. Great consistency, low velocity but still a powder I'll use every time.

 

[Frank in the Laurels]

Is your barrel length the same as the rest barrel listed ?? You know it doesn't take much with these slower powders to cause a drop in velocity. Plus about a million other variables other than temp, neck tension, neck area clearance etc etc etc....lots of variables for 100-200 fps... Maybe the chrony was having a bad sky day, not unheard of. If this is a hunting rifle I don't think the kill zone will miss 100 fps much...it'll still be deader than a doornail if you do your part. That's why my love affair with H-4350 is so great...a tad bit quicker and a hair slower but it's always consistent for me.

 

[tbrice23]

Once I had found a very good and fast load for my 300WM.
3130 fps with 185gr VLD at 79gr. 4831sc in a 24" barrel. And this load had noticeably less recoil than H1000.

The only problem was after a couple of firings the primer pockets showed more expansion than I'd like to see with Winchester brass. So I switched to 7828ssc.

I kept the load info for future reference, maybe someday if I decide todecide to use RWS brass it may be able to hold those pressures better for a few more firings than the Winchester.