Sierra 260 rem data?

[6.5grendel]

I just subscribed to Sierras load data app. I was mainly comparing its 142 gr loads with h4350 and h4831sc with hogdon's online data. Hogdon's starting loads are higher than Sierras max loads. Sierras max loads seem low at 40.7 gr h4350 and 44.4 gr. H4831sc. Does that sound right or is that pretty low? I am starting a new load workup and was looking for an approximate starting and stopping point.

 

[284winner]

I just subscribed to Sierras load data app. I was mainly comparing its 142 gr loads with h4350 and h4831sc with hogdon's online data. Hogdon's starting loads are higher than Sierras max loads. Sierras max loads seem low at 40.7 gr h4350 and 44.4 gr. H4831sc. Does that sound right or is that pretty low? I am starting a new load workup and was looking for an approximate starting and stopping point.

It's not really all that low. I think my .260 loads with H4831sc is 46.5 grains with the 142s. Getting 2860 fps with very good accuracy. Probably am not at even real close to compressed but fairly hot. Thinking it would be considered 80-90%. Accuracy and safety are what the manuals strive for I believe. Balancing both keeps the charge down a bit I believe even tho many of my loads are close to max and are the most accurate.

 

[MikeMcCasland]

I'm looking at my data across multiple .260 barrels, and that H4350 max load is way low (at least in Lapua brass). I was running 142 SMKs around 42.5 and getting 2780 FPS. I wasn't pushing them hard either; I suspect you could get a 142 upwards of 2850 pretty easily in a .260.

Their H4831 seems to be in the ballpark though. My last .260 barrel I was shooting 45.5gr behind a 130 Berger doing 2870. It wasn't nearly as fast as H4350, but it was more accurate and had lower SDs.

 

[JTMPILOT]

I'm using 47.0 grns 4831SC with the 139 Lapua Scenar. 2900 FPS in a 28 inch barrel.

 

[Racebannon3855]

I just subscribed to Sierras load data app. I was mainly comparing its 142 gr loads with h4350 and h4831sc with hogdon's online data. Hogdon's starting loads are higher than Sierras max loads. Sierras max loads seem low at 40.7 gr h4350 and 44.4 gr. H4831sc. Does that sound right or is that pretty low? I am starting a new load workup and was looking for an approximate starting and stopping point.

Nobody has mentioned overall cartridge length, differences in chambers or different primers. Those can make a big difference.

I am with you on using H4831 SC, it meters nice and everything that I have tried it in liked it.

If you have not called out to Sierra you might want to try it. Whenever I have a question I call them and they have always been great to work with over the phone. Hope it shoots great for you.

 

[GWY]

Another variable to consider is different lots of 4831SC were probably used by Sierra and Hodgdon in establishing their data.

In my 260, my latest lot of H4831SC was approximately 90fps slower with the same components than my old lot (about 2 years old). I gradually increased my powder charge to get back to my original velocity with no excessive pressure signs using this new lot

 

[6.5grendel]

Hogdon and Sierra do list different coal's. Hogdon has 2.780 coal and Sierra has 2.800 for coal. From that I would think hogdon would have a lower max charge weight. They do list different primers used though. They could also be using slightly different chambers which I didn't think about. My chamber has .160 free bore and my coal is around 2.88? to the lands.

 

[BIG D]

As always. Start low and work up until you find pressure limit. Stay below those limits. I’ve found manuals to be very safe loads. Your chamber will determine pressures as will the barrel, rifle, lot of brass, bullets, powder etc.

 

[Delfuego]

I ran 41.5 of H4350 with a 142SMK to get 2850fps +/-
Work up slow. Your brass, powder lots, barrel and primers will all have an effect on your speed.

 

[Fast14riot]

I use 44gr of H4831 with 140rdf for fire forming AI brass. Accurate and not really hot.

 

[284winner]

I'm using 47.0 grns 4831SC with the 139 Lapua Scenar. 2900 FPS in a 28 inch barrel.

The 139 scenars shot the best in my one 260. My barrel length was 25" and 2860 with 4831sc was getting close to the top. Could have shot faster but gain was minimal after 46.5 grains. Accuracy was the very best at 46.5. 139-142s were all very accurate in all my 260s. 4350 was a bit faster but a bit less accurate. Wish I'd have tried RL23/26 in them. Never had a reason with accuracy as good as it was so decided to leave alone what didn't need fixing.

 

[BAT man]

I would also recommend reloader 23 in the .260 with a 142 smk. It runs extremely well I my .260 ackley.