Thread: Belmont rifle powder 763

Originally Posted by Tentman

I haven't shot the loads but I'm using 62.6 mm OAL, If let me know what OAL you are using, barrel length and if possible case capacity of H2O I'll run a model for the 75's for you

Cheers for the offer, I appreciate it. I've been getting to grips with GRT myself thanks to our favourite 6.5 Grendel aficionado and all around reloading nerd @Pommy.

There's lots of fun to be had once you understand how all the variables interact. Based on the data from several other load combos I've been able to work out some data to try out the 763 with the 77 TMK ��

Originally Posted by Steelisreal

Cheers for the offer, I appreciate it. I've been getting to grips with GRT myself thanks to our favourite 6.5 Grendel aficionado and all around reloading nerd @Pommy.

There's lots of fun to be had once you understand how all the variables interact. Based on the data from several other load combos I've been able to work out some data to try out the 763 with the 77 TMK ��

I will be very interested in your results.

The results I have had with GRT and MR2000 ( 763) have been right on the money, validated speeds with Labradar
Even the OBT seems to give better accuracy results, by going to the node / 1/2 node.

Originally Posted by Steelisreal

Cheers for the offer, I appreciate it. I've been getting to grips with GRT myself thanks to our favourite 6.5 Grendel aficionado and all around reloading nerd @Pommy.

Aww shucks.

763 does turn speed up to 11 over AR2208. Sadly I've not always been able to get the same kind of accuracy and consistency once I get above 2208 speeds, making 763 a bit fruitless at times. I've often been better off leaving it dialled "down" to 10 and using AR2208.

Note that with my testing, I'm usually working up to predicted OBT nodes (plus going in and around them) after refining variables based on initial chrono results. So when I say one powder delivers me better accuracy than another, I have used the same methodology to get what I believe is the best I can hope to achieve with each powder for comparison.

223 was interesting. My notes are lacking here, but iirc 55gr had to be doing over 3300 from a 24" tube before the cases even started obturating properly. It topped out over 3500 with a shitty ES. Really think it need the heavier bullets in that application so your 75's and 77's should go well. Just stay away from redlining it due to the temp sensitivity. 2208 wasn't great either - too slow burning - but 2206H seems to be the ticket with 69's after chopping it to 21" and it avoids compression. I could get a little more speed with 763 but not enough to get to the higher OBT node where I'd expect to find the same consistent accuracy that 2206H gives at nearly 3k.

In 308, 763 got 208 ELD-M's up to really good speed and accuracy started out amazing but went further south the faster it went - the light rifle was getting very jumpy which didn't help get objective results here. OTOH it got 180 Gamekings doing 2750 very nicely from a 28" Encore. Similar accuracy to 2208 with a great ES (std large rifle). This speed is very doable with 2208 but I've stuck with 763 because it's clearly doing it with a lot less pressure. Chucked this load in a mates rifle which we feared might have been a lemon and it shot 10x better than his existing ammo which was to blame.

In 6.5x47L, 763 got silly speeds with 107gr TMK's, but the ES was horrible (magnum small primer) and I even got a hang fire on a cold morning, so I went back to 2208 even before doing any OBT comparisons. Many many roos and goats have met extremely violent ends from that bullet with 2208 since.

In 284, I got great speed with 100gr hollowpoints, around 3400, but 2208 gave slightly better accuracy and a single digit ES at 3315 which I couldn't ignore (br primer).

It's definitely gone well in 6.5 Grendel with heavy bullets. Mainly because you can fit so much more into the case over extruded powders. Accuracy has been on-par with 8208 and ES/SD has been even better (sr magnum primer) although the rifle seems to shoot everything extremely well so the accuracy element here is a bit meaningless. I've found the Speer data that I started from to be extremely conservative and barely even got case obturation at the published "max" load.

300WSM. 130gr TTSX going 3575fps. It's holding about 0.75 MOA out to 380m (longest shot with that load so far) which is on par with what I've managed with 2208. 2208 is giving slightly better ES/SD (lr magnum primer) but 763 is doing it with a lot less pressure.

That's about the sum of it so far. It definitely gives more speed. That extra speed can't always be combined with the same accuracy and consistency. Data is scarce but I might even go so far as to say that "your max load of 2208 can be your start load for 763" if you cannot find any.

@Marty Henry

Did you ever try this powder with your 9.3?

No, I've taken a liking to it in my 3006, after a bit more investigation ar2206h turns out to be fine in the 9,3x57

@Brian and @ANOTHERHUNTER use it in all sorts of weird and wonderful calibers.