I’ve been using H4895 but that long stick grain gives me a compressed load past 45.5 gr. Is there anything else out there that is more temp sensitive yet finer grained so I can get a bit more in?

I wouldn't call H4895 a long stick powder.

I also don't think H-4895 is long stick powder but, Ramshot TAC has been highly praised.

8208xbr is very temp stable, very short grained and right in the same speed range.

Varget is another stable powder giving similar velocities to H4895.


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Ok H4895 may not be truly long stick, but it’s not fine grained either. I’ve used TAC, but didn’t think it was all that temp stable. At least not in hot weather. How does the grain of Varget compare in size?

You're probably going to want to go a bit quicker than Varget.

Yup. Either 8208-XBR or Benchmark are both great choices if you don't want to use a ball powder.

I don't know how the temp sensitivity is but my 358 really likes IMR 4320. So do I as it is short grained and meters very well.

Dale

There is where I would start.

Can anyone compare the grain structure of H4895 and H4198? Doesn’t look like I’d need as much 4198 and wouldn’t have the compressed load issues.

TAC

TAC works great. Ramshot Xterminator works as well, maybe better in mine and my .356 Win.

I have some TAC but haven’t seen it verified as temp stable. Anybody have some cool/cold to hot weather numbers?

Look at Benchmark. I played with everything viable in my 338 Federal and ran into the same problem. Benchmark allowed 100% case capacity, no compressed charges, equal velocity, and is finer grained than H4895 and the like. Plus it shoots the best in my 338

OP, I don't have any 4895 at present to compare to H4198, but the latter has very short granules and they have the smallest diameter of any extruded powder I can recall.

I shot a deer in December here with 51.0 TAC and the 200 Hornady with no problems. I don't think there's really much of an issue.

I can vouch for IMR 8208XBR in the .358 Win.

May have been luck, but I loaded up 5 rounds to kill an old 1 lb bottle the other day, using 225 SGK's and CCI-200 primers in Starline brass: 4 shots into 0.19" and one unexplained flier (I was shooting quickly) opened up the group to about 0.8". Velocity was respectable if not impressive at ~2420 fps. Curiously, the SD and ES were substantially higher than my go-to load of 46.0 grains of H4895 (routinely a 0.6–0.7 MOA load in my rifle).

I've gotten higher velocity and only slightly looser groups with AA2230/X-Terminator and Varget, and TAC has been the velocity king but definitely more temp sensitive than Varget. I'll look through my notes this evening and see if I can find some temp/velocity numbers for you.

I'd give 8208XBR, Varget, and TAC a shot in that order.

I’m not worried about December. It’s July-Sept that concerns me.

Found some interesting data. Seems TAC's temperature sensitivity is bullet-dependent in my rifle.

With Barnes 200 TTSX:

date bullet powder grains velocity temp
1/27/18 200 TTSX TAC 50.0 2557
4/29/18 200 TTSX TAC 50.0 2667
7/14/18 200 TTSX TAC 49.5 2705 87

With Nosler 225 Partition:

date bullet powder grains velocity temp
9/21/17 225 Partition TAC 48.0 2393
4/29/18 225 Partition TAC 48.4 2458
5/6/18 225 Partition TAC 48.4 2459
7/6/18 225 Partition TAC 48.4 2459 90

Unfortunately I'm not all that consistent about recording temperature, but you get the general picture. The same brass (Starline) and primers (CCI-250) were used in all loads with the possible exception of that September 21 load, which may have been in necked-up LC 308 brass. Shooting Partitions, the average velocity was extremely stable using 48.4 grains of TAC. Same obviously can't be said for the 200 grain TTSX, which got a bit scary when things heated up.

My bad, I was thinking POI shift. I worked that load up in the summer in a BLR without any issues. There was a thread on TAC's temp stability:

https://www.24hourcampfire.com/ubbt.../11936095/Ramshot_TAC_temperature_sensit