30-06 180gr Sierra spbt H4350 load data

[Gtscotty]

Today I tried my first round of reloads using 180gr Sierra spbt bullets and Hodgdon load data, which has always coincided well with the actual velocities I see out of my rifles. My rifle seemed to favor 56gr and 57.5gr loads, the 57.5gr being book max in the Hodgdon data. None of the loads I tried showed any pressure signs, primers still have some edge curve and extraction is effortless.

On the way home I stopped by Sportsman's warehouse, and took a look at the Sierra load manual they had there... to my surprise, the listed max for the 180 gr spbt was 53.6 gr! I use several load data sources, and obviously a grain or so variance in top loads is common, but 4 grains? To make things worse, my standard load for deer in this rifle with 165gr spbt is Hodgdon book max at 59gr H4350. The Sierra manual lists a max load for this bullet of around 54gr.... 5gr is a big difference.

So what gives, what kind of experience have yall had with H4350 and heavier 30-06 loads? My velocities mesh well with the Hodgdon data, but the bullet maker's max loads are sooo far off from the powder maker's max loads, it worries me.

p.s.~ Nosler lists max with the 180gr Partition as 56.5gr, and I've always heard that the Partition usually generates higher pressure with a given load.

 

[gamestalker]

I'm don't have any Sierra 30-6 data handy at the moment, but I would have to agree that a 4.0 gr. or 5.0 gr. seems pretty significant and would be hard to turn a blind eye to. But OTOH, I see fairly big contradicting variations in data from one publisher to the next all the time.

One particular example is a load I run in 300 WM using IMR-7828. The same bullet, a 165 gr. Speer BTSP.

Speer shows a table of 79.0 grs. - 83.0 grs.
Hogdon table is 74.0 grs. - 79.5 grs.

That right there puts Speer starting charge at .5 gr. under the published max according to Hogdon, and 3.5 grs. above Hodgdon's published max. As I've said, I see conflicts like this all the time, and as along as I'm doing my part by using a proper load development procedure, working up from a reasonable point, I've not experienced any reason to be concerned.

IMO, and based on experience with conflicting data with significant variations, is that if the load is performing fine, no indications of a pressure issue as you've determined by bolt lift and primer flow appearance, I would continue using your worked up load, while keeping an eye on things.

GS

 

[ku4hx]

My old '60s vintage Remington 700 loves 4350 (either I or H) with 180 grain bullets. Availability was the driving factor for going with IMR 4350 but I've never regretted it. I like Sierra just fine, but again availability chose Hornady Interlock bullets for me.

56 grains of IMR 4350 and the Hornady bullet shows an average MV of 2,708 fps via my PACT2 that groups 1 MOA or less all day long. What little H4350 I tried way back when had similar results. Honestly, I'd go with either now days.